Astronomy blog By Dave Samuhel, AccuWeather senior meteorologist 2/26/2017, 4:44:03 PM

The new moon will enter the evening sky through the course of this week. The very thin waxing crescent will appear near Venus on Tuesday night. It will not be far from Mars on Wednesday night.

Jupiter will overtake the Venus as the night skys most impressive planet as we head into March.

insert Jupiter map

Jupiter rises a bit before midnight. It will continue to rise earlier and earlier, and will soon be in the sky through the entire night. Later in March, Mercury will be easier to spot in the evening sky.

Image Credit: AccuWeather Astronomy friend Ronald Shawley took this imagery Saturday night.

There is no active meteor shower at this time, but there have been a decent amount of fireball reports. Interestingly enough, the American Meteor Society reports that, evening fireballs seem to peak this time of year as seen from the Northern Hemisphere. Read the rest of their weekly meteor activity report here.

There is a lot to see in the night sky this week. So, just look up! You never know what you will see!

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The night sky this week - AccuWeather.com (blog)

Resembling an opulent diamond tapestry, this image from NASAs Hubble Space Telescope shows a glittering star cluster that contains a collection of some of the brightest stars seen in our Milky Way galaxy. Called Trumpler 14, it is located 8,000 light-years away in the Carina Nebula, a huge star-formation region. Credit: NASA, ESA, and J. Maz Apellniz (Institute of Astrophysics of Andalusia, Spain)

Astronomers are borrowing principles applied in biology and archaeology to build a family tree of the stars in the galaxy. By studying chemical signatures found in the stars, they are piecing together these evolutionary trees looking at how the stars formed and how they are connected to each other. The signatures act as a proxy for DNA sequences. Its akin to chemical tagging of stars and forms the basis of a discipline astronomers refer to as galactic archaeology.

It was Charles Darwin, who, in 1859 published his revolutionary theory that all life forms are descended from one common ancestor. This theory has informed evolutionary biology ever since but it was a chance encounter between an astronomer and an biologist over dinner at Kings College in Cambridge that got the astronomer thinking about how it could be applied to stars in the Milky Way.

Writing in Monthly Notices of the Royal Astronomical Society, Dr. Paula Jofr, of the University of Cambridges Institute of Astronomy, describes how she set about creating a phylogenetic tree of life that connects a number of stars in the galaxy.

The use of algorithms to identify families of stars is a science that is constantly under development. Phylogenetic trees add an extra dimension to our endeavours which is why this approach is so special. The branches of the tree serve to inform us about the stars shared history, she says.

The team picked 22 stars, including the Sun, to study. The chemical elements have been carefully measured from data coming from ground-based high-resolution spectra taken with large telescopes located in the north of Chile. Once the families were identified using the chemical DNA, their evolution was studied with the help of their ages and kinematical properties obtained from the space mission Hipparcos, the precursor of Gaia, the spacecraft orbiting Earth that was launched by the European Space Agency and is almost halfway through a 5-year project to map the sky.

Stars are born from violent explosions in the gas clouds of the galaxy. Two stars with the same chemical compositions are likely to have been born in the same molecular cloud. Some live longer than the age of the universe and serve as fossil records of the composition of the gas at the time they were formed. The oldest star in the sample analysed by the team is estimated to be almost ten billion years old, which is twice as old as the Sun. The youngest is 700 million years old.

In evolution, organisms are linked together by a pattern of descent with modification as they evolve. Stars are very different from living organisms, but they still have a history of shared descent as they are formed from gas clouds, and carry that history in their chemical structure. By applying the same phylogenetic methods that biologists use to trace descent in plants and animals it is possible to explore the evolution of stars in the galaxy.

The differences between stars and animals is immense, but they share the property of changing over time, and so both can be analysed by building trees of their history, says Professor Robert Foley, of the Leverhulme Centre for Human Evolutionary Studies at Cambridge.

With an increasing number of datasets being made available from both Gaia and more advanced telescopes on the ground, and on-going and future large spectroscopic surveys, astronomers are moving closer to being able to assemble one tree that would connect all the stars in the Milky Way.

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Mapping the family tree of stars Astronomy Now - Astronomy Now Online

Astronomys Moveable Feast

By late February, signs of spring are in the air in the Northland. Stretches of warm days get us thinking about stowing the sweatshirts and pulling out Hawaiian shirts. Spring training baseball games begin (today, in fact) just a couple of hours south of us, and Girl Scout cookies make their triumphant return to our lives. In the stores, clutches of candy eggs engulf shelves, reminding us that Easter is on its way. For many of us, this then means checking our calendar to figure out just when Easter falls this year, for it is a moving target and never on the same date in consecutive years.

Of all the major holidays we recognize in the Unites States, in fact, none requires as much calendar checking as Easter. This celebration of renewal may fall on any of 35 possible dates and cant even claim a home month; in some years it lands in March while in others it extends into April. The reasons for this inconsistency span centuries and involve astronomical phenomena, religious customs and evolving civil calendars.

We commonly remember the date of Easter as the first Sunday after the first full moon on or after the Vernal Equinox. But alas, this purely astronomical definition is not quite accurate due to a few problems.

Nearly 1,700 years ago, religious leaders began creating several parameters to define Easter: first, for the purposes of figuring Easter, the Vernal Equinox is set at March 21 (even though in reality it can also land on March 19 or 20). Second, Easter must be on a Sunday, and that Sunday must be the first one after the paschal full moon.

A paschal full moon is defined as taking place on the 14th day of an arbitrary lunar month and occurs on or directly after March 21. The paschal full moon is based on ecclesiastical tables, rather than astronomical observations. Because of this, the paschal full moon does not necessarily correspond exactly to the time of the astronomical full moon.

Taking all of these parameters into consideration, we find that Easter can fall on a number of different days, ranging from as early as March 22 to as late as April 25 (April 16 this year). Moreover, the dates follow a sequence that repeats every 5,700,000 years or so in our current Gregorian calendar. Of course, for those who dont follow the Gregorian calendar, or for groups including certain Eastern Orthodox churches that dont follow the above definition of Easter, the date for this special day may vary in any given year.

Because of its fluctuating dates Easter is known as a moveable feast; not the Paris version of Hemingway but the religious variety describing a feast day that occurs on different days each year.

No matter how the date of Easter has been defined, one thing that has remained consistent through the years is its celebration in the spring, that time of rebirth and renewal, resurrection and the restoration of life, Girl Scout cookies and baseball.

Kevin Schindler is the Lowell Observatory historian

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Easter: Astronomy's moveable feast - Arizona Daily Sun

"Stargazing" redirects here. For the television programme, see Stargazing Live.

Amateur astronomy is a hobby whose participants enjoy watching the sky, and the abundance of objects found in it with the unaided eye, binoculars, or telescopes. Even though scientific research is not their main goal, many amateur astronomers make a contribution to astronomy by monitoring variable stars, tracking asteroids and discovering transient objects, such as comets and novae.

The typical amateur astronomer is one who does not depend on the field of astronomy as a primary source of income or support, and does not have a professional degree or advanced academic training in the subject. Many amateurs are beginners or hobbyists, while others have a high degree of experience in astronomy and often assist and work alongside professional astronomers.

Amateur astronomy is usually associated with viewing the night sky when most celestial objects and events are visible, but sometimes amateur astronomers also operate during the day for events such as sunspots and solar eclipses. Amateur astronomers often look at the sky using nothing more than their eyes, but common tools for amateur astronomy include portable telescopes and binoculars.

People have studied the sky throughout history in an amateur framework, without any formal method of funding. It is only within about the past century, however, that amateur astronomy has become an activity clearly distinguished from professional astronomy, and other related activities.

Collectively, amateur astronomers observe a variety of celestial objects and phenomena. Common targets of amateur astronomers include the Moon, planets, stars, comets, meteor showers, and a variety of deep sky objects such as star clusters, galaxies, and nebulae. Many amateurs like to specialise in observing particular objects, types of objects, or types of events which interest them. One branch of amateur astronomy, amateur astrophotography, involves the taking of photos of the night sky. Astrophotography has become more popular with the introduction of far easier to use equipment including, digital cameras, DSLR cameras and relatively sophisticated purpose built high quality CCD cameras.

Most amateur astronomers work at visible wavelengths, but a small minority experiment with wavelengths outside the visible spectrum. An early pioneer of radio astronomy was Grote Reber, an amateur astronomer who constructed the first purpose built radio telescope in the late 1930s to follow up on the discovery of radio wavelength emissions from space by Karl Jansky. Non-visual amateur astronomy includes the use of infrared filters on conventional telescopes, and also the use of radio telescopes. Some amateur astronomers use home-made radio telescopes, while others use radio telescopes that were originally built for astronomy research but have since been made available for use by amateurs. The One-Mile Telescope is one such example.

Amateur astronomers use a range of instruments to study the sky, depending on a combination of their interests and resources. Methods include simply looking at the night sky with the naked eye, using binoculars, and using a variety of optical telescopes of varying power and quality, as well as additional sophisticated equipment, such as cameras, to study light from the sky in both the visual and non-visual parts of the spectrum. Commercial telescopes are available, new and used, but it is also common for amateur astronomers to build (or commission the building of) their own custom telescopes. Some people even focus on amateur telescope making as their primary interest within the hobby of amateur astronomy.

Although specialized and experienced amateur astronomers tend to acquire more specialized and more powerful equipment over time, relatively simple equipment is often preferred for certain tasks. Binoculars, for instance, although generally of lower power than the majority of telescopes, also tend to provide a wider field of view, which is preferable for looking at some objects in the night sky.

Amateur astronomers also use star charts that, depending on experience and intentions, may range from simple planispheres through to detailed charts of very specific areas of the night sky. A range of astronomy software is available and used by amateur astronomers, including software that generates maps of the sky, software to assist with astrophotography, observation scheduling software, and software to perform various calculations pertaining to astronomical phenomena.

Amateur astronomers often like to keep records of their observations, which usually takes the form of an observing log. Observing logs typically record details about which objects were observed and when, as well as describing the details that were seen. Sketching is sometimes used within logs, and photographic records of observations have also been used in recent times. The information gathered is used to help studies and interactions between amateur astronomers in yearly gatherings. Although not professional information or credible, it is a way for the hobby lovers to share their new sightings and experiences.

The Internet is an essential tool of amateur astronomers. The popularity of CCD imaging among amateurs has led to large numbers of web sites being written by individuals about their images and equipment. Much of the social interaction of amateur astronomy occurs on mailing lists or discussion groups. Discussion group servers host numerous astronomy lists. A great deal of the commerce of amateur astronomy, the buying and selling of equipment, occurs online. Many amateurs use online tools to plan their nightly observing sessions using tools such as the Clear Sky Chart.

While a number of interesting celestial objects are readily identified by the naked eye, sometimes with the aid of a star chart, many others are so faint or inconspicuous that technical means are necessary to locate them. Although many methods are used in amateur astronomy, most are variations of a few specific techniques.

Star hopping is a method often used by amateur astronomers with low-tech equipment such as binoculars or a manually driven telescope. It involves the use of maps (or memory) to locate known landmark stars, and "hopping" between them, often with the aid of a finderscope. Because of its simplicity, star hopping is a very common method for finding objects that are close to naked-eye stars.

More advanced methods of locating objects in the sky include telescope mounts with setting circles, which assist with pointing telescopes to positions in the sky that are known to contain objects of interest, and GOTO telescopes, which are fully automated telescopes that are capable of locating objects on demand (having first been calibrated).

Setting circles are angular measurement scales that can be placed on the two main rotation axes of some telescopes. Since the widespread adoption of digital setting circles, any classical engraved setting circle is now specifically identified as an "analog setting circle" (ASC). By knowing the coordinates of an object (usually given in equatorial coordinates), the telescope user can use the setting circle to align the telescope in the appropriate direction before looking through its eyepiece. A computerized setting circle is called a "digital setting circle" (DSC). Although digital setting circles can be used to display a telescope's RA and Dec coordinates, they are not simply a digital read-out of what can be seen on the telescope's analog setting circles. As with go-to telescopes, digital setting circle computers (commercial names include Argo Navis, Sky Commander, and NGC Max) contain databases of tens of thousands of celestial objects and projections of planet positions.

To find an object, such as globular cluster NGC 6712, one does not need to look up the RA and Dec coordinates in a book, and then move the telescope to those numerical readings. Rather, the object is chosen from the database and arrow markers appear in the display which indicate the direction to move the telescope. The telescope is moved until the distance value reaches zero. When both the RA and Dec axes are thus "zeroed out", the object should be in the eyepiece. The user therefore does not have to go back and forth from some other database (such as a book or laptop) to match the desired object's listed coordinates to the coordinates on the telescope. However, many DSCs, and also go-to systems, can work in conjunction with laptop sky programs.[citation needed]

Computerized systems provide the further advantage of computing coordinate precession. Traditional printed sources are subtitled by the 'epoch year, which refers to the positions of celestial objects at a given time to the nearest year (e.g., J2005, J2007). Most such printed sources have been updated for intervals of only about every fifty years (e.g., J1900, J1950, J2000). Computerized sources, on the other hand, are able to calculate the right ascension and declination of the "epoch of date" to the exact instant of observation.

GOTO telescopes have become more popular since the 1980s as technology has improved and prices have been reduced. With these computer-driven telescopes, the user typically enters the name of the item of interest and the mechanics of the telescope point the telescope towards that item automatically. They have several notable advantages for amateur astronomers intent on research. For example, GOTO telescopes tend to be faster for locating items of interest than star hopping, allowing more time for studying of the object. GOTO also allows manufacturers to add equatorial tracking to mechanically simpler alt-azimuth telescope mounts, allowing them to produce an overall less expensive product. GOTO telescopes usually have to be calibrated using alignment stars in order to provide accurate tracking and positioning. However, several telescope manufacturers have recently developed telescope systems that are calibrated with the use of built-in GPS, decreasing the time it takes to set up a telescope at the start of an observing session.

With the development of fast Internet in the last part of the 20th century along with advances in computer controlled telescope mounts and CCD cameras 'Remote Telescope' astronomy is now a viable means for amateur astronomers not aligned with major telescope facilities to partake in research and deep sky imaging. This enables anyone to control a telescope a large distance away in a dark location. The observers can image through the telescopes using CCD cameras. The digital data collected by the telescope is then transmitted and displayed to the user by means of the Internet. An example of a digital remote telescope operation for public use via the Internet is the The Bareket Observatory, and there are telescope farms in New Mexico,[2]Australia and Atacama in Chile.[3]

Amateur astronomers engage in many imaging techniques including film, DSLR, LRGB, and CCD astrophotography. Because CCD imagers are linear, image processing may be used to subtract away the effects of light pollution, which has increased the popularity of astrophotography in urban areas. Narrowband filters may also be used to minimize light pollution.[4]

Scientific research is most often not the main goal for many amateur astronomers, unlike professional astronomers. Work of scientific merit is possible, however, and many amateurs successfully contribute to the knowledge base of professional astronomers. Astronomy is sometimes promoted as one of the few remaining sciences for which amateurs can still contribute useful data. To recognize this, the Astronomical Society of the Pacific annually gives Amateur Achievement Awards for significant contributions to astronomy by amateurs.

The majority of scientific contributions by amateur astronomers are in the area of data collection. In particular, this applies where large numbers of amateur astronomers with small telescopes are more effective than the relatively small number of large telescopes that are available to professional astronomers. Several organizations, such as the American Association of Variable Star Observers, exist to help coordinate these contributions.

Amateur astronomers often contribute toward activities such as monitoring the changes in brightness of variable stars and supernovae, helping to track asteroids, and observing occultations to determine both the shape of asteroids and the shape of the terrain on the apparent edge of the Moon as seen from Earth. With more advanced equipment, but still cheap in comparison to professional setups, amateur astronomers can measure the light spectrum emitted from astronomical objects, which can yield high-quality scientific data if the measurements are performed with due care. A relatively recent role for amateur astronomers is searching for overlooked phenomena (e.g., Kreutz Sungrazers) in the vast libraries of digital images and other data captured by Earth and space based observatories, much of which is available over the Internet.

In the past and present, amateur astronomers have played a major role in discovering new comets. Recently however, funding of projects such as the Lincoln Near-Earth Asteroid Research and Near Earth Asteroid Tracking projects has meant that most comets are now discovered by automated systems, long before it is possible for amateurs to see them.

There are a large number of amateur astronomical societies around the world, that serve as a meeting point for those interested in amateur astronomy. Members range from active observers with their own equipment to "armchair astronomers" who are simply interested in the topic. Societies range widely in their goals, which may depend on a variety of factors such as geographic spread, local circumstances, size, and membership. For example, a small local society in dark countryside may focus on practical observing and star parties, whereas a large one based in a major city might be limited by light pollution and thus hold regular indoor meetings with guest speakers instead. Major national or international societies generally publish their own journal or newsletter, and many hold large multi-day meetings akin to a scientific conference. They may also have sections devoted to particular topics, such as observing the Moon or amateur telescope making.

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Amateur astronomy - Wikipedia

On the night of February 23, 1987, the first light reached Earth from the death of a massive star in the nearby Large Magellanic Cloud (LMC). For those in the Southern Hemisphere, a new star appeared in the sky and remained visible to the naked eye for months, peaking in brightness in May of that year before it faded from view. Dubbed SN 1987A, this event occurred a mere 166,000 light-years away and provided astronomers with unparalleled insight into the end stages of massive stars. In celebration of the 30th anniversary of this event, NASA is releasing new images and information about SN 1987A.

SN 1987A has greatly furthered our understanding of the supernova process and the stages that both precede and follow it. In a press release, Robert Kirshner of the Harvard-Smithsonian Center for Astrophysics and the Gordon and Betty Moore Foundation explained, The 30 years' worth of observations of SN 1987A are important because they provide insight into the last stages of stellar evolution.

Thirty years ago, astronomers understanding of supernovae was limited at best, simply because no nearby events had been observed with any appreciable resolution. But SN 1987A is located in the Tarantula Nebula of the Milky Ways satellite galaxy, the LMC, and was the brightest supernova visible from Earth since 1604. Although ground-based telescopes were only able to resolve the resulting remnant as a small blob, the Hubble Space Telescope (HST) began taking high-resolution images of SN 1987A in 1990, revealing in detail the structure surrounding this former star.

Astronomers have continued to image SN 1987A in great detail with HST and other telescopes over the years, including the Chandra X-ray Observatoryand, more recently, the Atacama Large Millimeter/submillimeter Array (ALMA). These images have revealed a ring-like structure around the supernovas progenitor star that was ejected from the star 20,000 years before its explosive death. Not only is there a main ring surrounding the supernova remnant, but two outer rings as well that give the object an hourglass shape.

The rings have been illuminated more than once first, by the light from the initial supernova explosion, and then again several years later, in 2001, as slower-moving shock waves caused by the explosion finally reached the distance of the rings. By observing the rings over time in various wavelengths of light, astronomers have been able to draw a clearer picture of the composition and structure of the gas surrounding the once-18-solar mass star. In turn, the characteristics of this structure will shed light on the late stages of this stars life before it exploded.

But for all that weve learned about SN 1987A, theres still a lot we dont know. For example, two hours before the optical light from the supernova was first seen, neutrino detectors deep underground in Japan and the United States registered a wave of neutrinos from the star. These detections point to the formation of a compact object, either a neutron star or black hole, as the star exploded. At 18-20 times the mass of the sun, the star that created SN 1987A could have left either option behind. But thus far, astronomers have not been able to find either object at the center of the remnant.

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Celebrate Supernova 1987A's 30th birthday with a stellar image set - Astronomy Magazine

[Artwork depicting the Milky Way and Virgo I, more or less to scale. Credit:NASA/JPL-Caltech/Robert Hurt]

Galaxies are immense structures. Composed of gas, dust, dark matter, and billions of stars, big ones can be a hundred thousand light-years across a million trillion kilometers and have masses equaling trillions of Suns.

Our own Milky Way fits those numbers pretty well. It formed not long after the Universe, itself, did, probably a billion or so years after the Big Bang, collapsing from a vast cloud of hydrogen and helium gas. It wasnt alone, though: Two other big galaxies were born along with it (the Andromeda Galaxy and Triangulum), and a handful of smaller ones that are all bound by their mutual gravity, forming what we call the Local Group.

Some of these galaxies are actually satellites of the Milky Way, in a similar way that the Moon is a satellite of Earth. The two biggest are the Large and Small Magellanic Clouds, with about 10 billion and a few hundred million stars in them respectively, but we know of a few dozen very small dwarf galaxies also in orbit around us. Most of them are extremely faint and hard to detect, and were not really sure how many there are in total.

Thats actually important to know. Different theories and models of how galaxies form predict different numbers and distributions of dwarf satellite galaxies. To differentiate them, astronomers scan the skies looking for more Milky Way companions.

These surveys are paying off: Nine dwarf candidate (meaning as yet unconfirmed) satellites were found in 2015. Late last year, in 2016, another was discovered, and its pretty cool.

It was found using the Hyper Suprime-Cam instrument on the gigantic Subaru 8.2 meter telescope. The HSC is itself a bit of a monster; its over two meters long, weighs three tons, and takes enormous 870 megapixel images that cover 1.5 of the sky on a side. The Moon is about 0.5, so this covers an area nearly ten times the area of the Moon.

Astronomers aimed it at five separate regions of the sky, covering a total of 100 square degrees (thats a lot). They mapped where all the objects were in the fields, separated stars from distant background galaxies (stars are point sources, whereas most galaxies are slightly extended), and then looked for places where there were more stars than expected hoping some might be faint Milky Way satellites.

In the constellation of Virgo, they found such a clump. Its unlikely to be a random fluctuation in the distribution of Milky Way stars masquerading as a physical clump; its better than 99% certain to be an actual object. To make sure, the astronomers did something clever. In an old dwarf satellite galaxy, its reasonable to assume all the stars in it were born at the same time; these galaxies tend to form stars right as the galaxy, itself, forms, then run out of gas to make any more. If the stars instead belong to our Milky Way they would have all different ages, since were still actively churning them out.

Using models of how stars change color as they age, the astronomers were able to show that the stars in the clump do look to be about the same age about 13 billion years. Not only that, if they throw away the stars that dont match that age, the statistical significance of the clump being real jumps up to near certainty.

So, this appears to be a real galaxy, which theyve dubbed Virgo I. The distance (measured by looking at the brightness of the stars in it) is about 280,000 light years away; three times the width of the Milky Way, itself. The size is a bit difficult to determine; galaxies arent solid objects and fade with distance from their centers. But it appears this object is roughly 300 light years across.

That, in itself, is interesting. First, thats tiny. Second, there are objects called globular clusters, which are magnificent collections of hundreds of thousands of stars in a ball, all orbiting their common center of mass like bees buzzing around a hive. About 150 of them are known to orbit the Milky Way. While the numbers of stars in a typical globular cluster is similar to Virgo I, the latter is much bigger than what youd expect for a globular at that distance, making it even more likely this is, indeed, a galaxy.

So, this looks to be a legit dwarf galaxy, likely a satellite of the Milky Way, so small and faint its escaped detection until now. Now, heres a fun fact: The astronomers looked at 100 square degrees of sky and found one such object. But there are over 40,000 square degrees of sky, so extrapolating from that means there may be hundreds of these dinky galaxies yet to find!

Happily, the survey that found Virgo I is ongoing, so hopefully theyll start finding more. Its rather amazing to me that we can see galaxies billions of light years way, nearly to the edge of the observable Universe, but there can be galaxies literally orbiting our own that have gone unnoticed. Of course, the ones we see at fantastic distances are huge and bright, and the nearby ones small and faint. But still, it shows you that, sometimes, treasures can be found on your doorstep if you just look more carefully.

Originally posted here:

Astronomers discover a new satellite for the Milky Way - Blastr

Biologist and educator Michael Ralbovsky.

Biologist and educator Michael Ralbovsky returns to New Pond Farm on Sunday, March 5, from 2 to 3:30 p.m.

Hell present an exciting, high-energy show bringing us reptiles from all parts of the world, according to a release.

He plans to share a giant toad, a six-foot lizard, an enormous tortoise, a very long crocodilian, and a snake!

Ralbovsky has worked with zoos across the country for more than 40 years, and with many high-profile celebrities, such as Jeff Corwin. He is known for his specialized classes teaching law enforcement officers how to handle reptiles safely and humanely.

This family program is $10 per New Pond Farm member and $15 per non-member.

Registration is required for all programs. Visit the farm online at http://www.newpondfarm.org or call 203-938-2117 to register.

On Saturday, March 4, at 7 p.m. New Pond Farm will host an astronomy program on Astronomy Hill for views of planets and winter constellations.

Please bundle up, and bring along binoculars if you have them and a flashlight. Please park by the Learning Center and walk out to the hill, a press release from the center said.

Families are invited to a special preview session in the Learning Center classroom at 6:30 p.m., before the outdoor program begins.

The cost for the program is $4 per New Pond Farm member (with a $16 maximum per member family) or $6 per non-member (with a $24 maximum per non-member family).

Registration is required for all programs. Visit http://www.newpondfarm.org or call 203-938-2117 to register.

New Pond Farm is located at 101 Marchant Road in Redding.

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Upcoming programs at New Pond Farm astronomy, reptiles - The Redding Pilot

Lyman-alpha emission is a specific wavelength of light given off by neutral hydrogen as it cools after heating that allows astronomers to trace the location of this gas. Lyman-alpha blobs are large structures of gas emitting at this wavelength that are associated with young galaxies in the early universe. The emission seen from these blobs is typically assumed to arise from the high levels of radiation given off by quasars, star formation, or even supernovae in the galaxies they surround. Astronomers have recently discovered one of the largest Lyman-alpha structures found to date, but the source of this huge objects glow is not exactly obvious.

MAMMOTH-1 is an enormous Lyman-alpha nebula, or ELAN for short. Its a huge structure of hydrogen gas that sits at a distance of 10 billion light-years from Earth in the center of a dense concentration of galaxies. Its discovery was announced in a paper accepted for publication in theAstrophysical Journal and also available online, authored by Zheng Cai, a Hubble Postdoctoral Fellow at UC Santa Cruz, and several associates. The structures name is derived from the survey that found it: Mapping the Most Massive Overdensities Through Hydrogen, or MAMMOTH.

MAMMOTH-1 is not the first ELAN to be discovered. Coauthor J. Xavier Prochaska, a professor of astronomy and astrophysics at UC Santa Cruz, found the first ELAN in 2014, known as the Slug Nebula.

MAMMOTH-1s location in and of itself isnt unusual, as Lyman-alpha blobs such as ELANs have been discovered around the highest densities of matter throughout the universe. However, what is unusual is that previously discovered ELANs are all associated with visible quasars, which provide an obvious mechanism responsible for the Lyman-alpha emission they produce. MAMMOTH-1 is not.

Quasars are intensely bright sources of radiation that arise from the disks of matter swirling around supermassive black holes. When a quasars high-energy photons hit hydrogen gas (such as that in MAMMOTH-1), they knock electrons away in a process called photoionization. The electrons are later recaptured by the hydrogen atoms, which gives off Lyman-alpha light. Alternatively, a quasar can produce outflows that heat the hydrogen gas of a Lyman-alpha blob via shocks, which also produces Lyman-alpha emission.

MAMMOTH-1 is extremely bright, and it's probably larger than the Slug Nebula, but there's nothing else visible except the faint smudge of a galaxy. So it's a terrifically energetic phenomenon without an obvious power source," said Prochaska in a press release.

MAMMOTH-1s home is a proto-cluster that consists of a huge number of galaxies spread out in a relatively large area just 3 billion years after the Big Bang. Given time to evolve, the protocluster should come to resemble the densely-packed galaxy clusters we see in our local universe today. Proto-clusters represent an early step in cosmic evolution, and its thought that gas flows along a cosmic web of invisible dark matter to form stars and galaxies. And, in fact, MAMMOTH-1 itself has a filamentary structure, which the team believes traces out the cosmic web thats growing the protocluster over time. Thus, MAMMOTH-1 acts as an illuminated portion of the cosmic web, showing astronomers where gas is flowing into this high-density area of the universe. According to Cai, From the distribution of galaxies we can infer where the filaments of the cosmic web are, and the nebula is perfectly aligned with that structure.

As for the mystery of MAMMOTH-1s power source, Cai and his coauthors speculate that its likely an active supermassive black hole thats simply obscured by dust and gas, and thus not readily visible in optical light. This idea is supported by evidence theyve gathered during their observations, including the dynamics of MAMMOTH-1s gas and the emission visible from elements other than hydrogen in the vicinity.

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Glow-in-the-dark gas lights up the cosmic web - Astronomy Magazine

After successfully completing its Key Decision Point-B review on February 15, NASAs Europa space exploration mission has been given the green light to move onto its initial design phase at the end of this month.

Every NASA mission must pass each stage of review, showing NASA that the mission meets all the requirements to complete the process and launch. Phase A includes conceptual study and preliminary analyses of the missions, phase B is preliminary designs, and phases C and D are final designs, creating the spacecraft, testing, and finally launching it.

In the Europa review, Phase A included picking out which instruments the team wanted to include on the spacecraft to study the potentially habitable moon. It had already started testing spacecraft components, but that will continue into phase B.

The current plan is to have the mission launch some time in the 2020s and orbit Jupiter as much as every two weeks, estimating between 40-45 flybys through the duration of the mission. Along with studying the structure of Europa and learning more about the composition of its ocean, the mission will take thousands of high-resolution images of the icy moon.

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The Europa mission is heading onto phase B - Astronomy Magazine

The gamma-ray excess (shown in yellow-white) at the heart of M31 hints at unexpected goings-on in the galaxys central region. Scientists think the signal could be produced by a variety of processes, including a population of pulsars or even dark matter. Credits: NASA/DOE/Fermi LAT Collaboration and Bill Schoening, Vanessa Harvey/REU program/NOAO/AURA/NSF

NASAs Fermi Gamma-ray Space Telescope has found a signal at the center of the neighboring Andromeda galaxy that could indicate the presence of the mysterious stuff known as dark matter. The gamma-ray signal is similar to one seen by Fermi at the center of our own Milky Way galaxy.

Gamma rays are the highest-energy form of light, produced by the universes most energetic phenomena. Theyre common in galaxies like the Milky Way because cosmic rays, particles moving near the speed of light, produce gamma rays when they interact with interstellar gas clouds and starlight.

Surprisingly, the latest Fermi data shows the gamma rays in Andromeda also known as M31 are confined to the galaxys center instead of spread throughout. To explain this unusual distribution, scientists are proposing that the emission may come from several undetermined sources. One of them could be dark matter, an unknown substance that makes up most of the universe.

We expect dark matter to accumulate in the innermost regions of the Milky Way and other galaxies, which is why finding such a compact signal is very exciting, said lead scientist Pierrick Martin, an astrophysicist at the National Center for Scientific Research and the Research Institute in Astrophysics and Planetology in Toulouse, France. M31 will be a key to understanding what this means for both Andromeda and the Milky Way.

A paper describing the results will appear in an upcoming issue of The Astrophysical Journal.

Another possible source for this emission could be a rich concentration of pulsars in M31s center. These spinning neutron stars weigh as much as twice the mass of the Sun and are among the densest objects in the universe. One teaspoon of neutron star matter would weigh a billion tons on Earth. Some pulsars emit most of their energy in gamma rays. Because M31 is 2.5 million light-years away, its difficult to find individual pulsars. To test whether the gamma rays are coming from these objects, scientists can apply what they know about pulsars from observations in the Milky Way to new X-ray and radio observations of Andromeda.

Now that Fermi has detected a similar gamma-ray signature in both M31 and the Milky Way, scientists can use this information to solve mysteries within both galaxies. For example, M31 emits few gamma rays from its large disk, where most stars form, indicating fewer cosmic rays roaming there. Because cosmic rays are usually thought to be related to star formation, the absence of gamma rays in the outer parts of M31 suggests either that the galaxy produces cosmic rays differently, or that they can escape the galaxy more rapidly. Studying Andromeda may help scientists understand the life cycle of cosmic rays and how it is connected to star formation.

We dont fully understand the roles cosmic rays play in galaxies, or how they travel through them, said Xian Hou, an astrophysicist at Yunnan Observatories, Chinese Academy of Sciences in Kunming, China, also a lead scientist in this work. M31 lets us see how cosmic rays behave under conditions different from those in our own galaxy.

The similar discovery in both the Milky Way and M31 means scientists can use the galaxies as models for each other when making difficult observations. While Fermi can make more sensitive and detailed observations of the Milky Ways center, its view is partially obscured by emission from the galaxys disk. But telescopes view Andromeda from an outside vantage point impossible to attain in the Milky Way.

Our galaxy is so similar to Andromeda, it really helps us to be able to study it, because we can learn more about our galaxy and its formation, said co-author Regina Caputo, a research scientist at NASAs Goddard Space Flight Center in Greenbelt, Maryland. Its like living in a world where theres no mirrors but you have a twin, and you can see everything physical about the twin.

While more observations are necessary to determine the source of the gamma-ray excess, the discovery provides an exciting starting point to learn more about both galaxies, and perhaps about the still elusive nature of dark matter.

We still have a lot to learn about the gamma-ray sky, Caputo said. The more information we have, the more information we can put into models of our own galaxy.

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Turner Farm to Hold 'Astronomy for Family Fun: Moon' Patch.com Observatory Park at Turner Farm is hosting an astronomy night for family members age six to adult that puts a focus on the moon. Learn about earth's natural satellite, and enjoy fun activities and crafts that will help to demystify the moon and bring ...

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Turner Farm to Hold 'Astronomy for Family Fun: Moon' - Patch.com

Like no other

That brings us to five planets. Intensive studies using both the TRAPPIST telescope and NASAs Spitzer telescope helped refine the orbit of the planets and drew out the presence of two more from the data. TRAPPIST-1b, -1c, -1f, and -1g are all very slightly larger than Earth. -1e is slightly smaller than Earth. -1d and -1h are closer to Mars in size.

While the exact masses and orbital periods arent known yet, preliminary results suggest that they may be in resonance. That means that when -1b orbits eight times, -1c completes five orbits, often marked as 8:5. -1c and -1d are in 5:3 resonance; -1d and -1e are in 3:2, as are -1e and -1f. -1f and -1g are in 4:3.

All of them seem to be in the habitable zone of TRAPPIST-1. That means that they could, under the right conditions, sustain surface water, but theres no proof that any of the planets do. For instance, in our solar system Venus and Mars are in the habitable zone, but both are fairly inhospitable in our present time.

Of the seven, the researchers believe that -1e, -1f, and -1g are the likeliest to be habitable based on where they sit in the solar system.

While seven planets have been confirmed, thats not all the system may hold in store.

It is just the beginning for many reasons there might be more on top of that, Julien de Wit, a co-author on the paper, says.

Slow your roll

There are other considerations before we declare the planets quite ripe for life, though. M-dwarf stars like TRAPPIST-1 tend to start out very active with high energy flare events. This could strip away the atmosphere of young planets.

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This tiny solar system packs in seven Earth-size planets - Astronomy Magazine

By Justin Smith | 02/23/2017 12:11am Sam MacDonald / Alabama Crimson White

TheDepartment of Physics and Astronomy'spublic observation night at the Moundville Archeological Park on Friday at 7 p.m.

Hollywood stars will shine on Sunday at the Oscars, but it will take a telescope to catch the real deal tomorrow night.

The Astronomy group within the Department of Physics and Astronomy will host its monthly public observation night at the Moundville Archeological Park on Friday at 7 p.m.

Every month the Astronomy group hosts a public night for people to come out and view the sky through several different telescopes on and off campus. The event is free to everyone and will end at 10 p.m. This is the third one this semester.

Ronald Buta, eventhost and astronomy professor, said they decided to use Moundville Archeological Park because campus had too much light pollution, making it difficult to view some of the things that they hope to capture.

We have one of the largest telescopes in the world to view things like the Orion Nebula, Buta said. The night sky has a lot of interesting things to see.

The Moundville Archeological park is a National Historic Landmark that contains over 26 large pyramid-shaped mounds within its 320 acres. The park is located approximately 16 miles south of Tuscaloosa.

Several members of the UA Astronomical Society will assist with the event.

UA Astronomical Society president and founder, Ray Schlsser, said he always encourages some members of the organization to help out in the public night in any way that they are needed.

The public nights are always packed, saidSchlsser,a senior majoring in astrophysics. Its a great way to meet new people, so I never have any complaints from any members about volunteering to be part of the event.

The Astronomical Society was founded for the purpose of introducing astrophysics majors to one another for career opportunities. They are currently in the process of planning trips to several graduate schools. The society will host its own observation nights later in the semester.

Our society gives younger students a great opportunity to meet others with their major, Schlsser said, This helps them make better decisions on which courses to take and which professor to select.

Spectators will get the opportunity to look at the night sky through telescopes of different sizes. The telescopes are going to be placed in front of the Moundville Archeological Museum. All are welcome to come and gaze at the night sky with Professor Buta and company.

This public night is one of the astronomy group's deep-sky observing sessions. The group will use their 16 inch and 17 inch telescopes to view some of the hidden features of the night sky.

There is also a good chance they will use their 20 inch telescope, "The Big Little Telescope," that was recently donated to the department. The telescope is set up on a pad in the field across the road from the museum. The park will not charge anyone for entering the park after hours.

Butasaid he is hoping that the weather will allow them to have a successful gazing experience. The skies were clear on the previous public night. If the weather does not permit, the event will be cancelled, with alerts on the astronomy department's website.

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Astronomy hosts public observing night - The Crimson While

When Robert Morehead was in high school in 1995, scientists discovered 51 Pegasi b the first planet to be found orbiting around a sun-like star.

That just blew my mind, said Morehead, who is now a Texas Tech instructor of physics and astronomy and director of the Preston Gott Observatory. I thought that was just so cool and how neat it was that they were able to find little balls of rock around distant stars. This may surprise you but its not the easiest thing to do and the people who found out the original techniques were pretty clever; it was pretty impressive.

Morehead felt that same excitement Wednesday after NASA announced the discovery of seven Earth-size planets orbiting closely around a single star. Three of those planets were described by NASA as being within the habitable zone.

The discovery sets a new record for greatest number of habitable-zone planets found around a single star outside our solar system, according to a NASA news release. All of these seven planets could have liquid water key to life as we know it under the right atmospheric conditions, but the chances are highest with the three in the habitable zone.

Morehead, who recently finished a dissertation on exoplanets and systems with multiple planets, said there are different ways to define habitable zone, but the key factor is liquid water.

(Habitable zone) means theyre close enough to their star that they get enough sunlight (and) theyre warm enough to have liquid water on their surface, he said. If you can have liquid water on the surface, (thats) one ingredient we think is absolutely necessary for life. Were not exactly sure, but all life on Earth has to have liquid water. Life can live in a hot spring or down in the bottom of a salt lake or stuff like that, but the one thing that it absolutely has to have is liquid water.

The latest discovery means scientists are one step closer to answering the question: Is there life outside of Earth?

Kind of the big picture what does this mean for life, the universe and everything (is that) every time we get a result like this, its looking more and more solid that theres probably a lot of potential real estate in the galaxy, Morehead said. That leads to all kinds of interesting questions.

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An SF State astronomy professor is making headway with his research on exoplanets that may have conditions to support life.

Stephen Kane, who teaches Introduction to Astronomy, Stellar Astrophysics and Exoplanetary Science at SF States physics and astronomy department had his work published in the latest issue of the prestigious peer-reviewed Astrophysical Journal, gaining him recognition in the science and astrophysics community, according to a University Communications press release.

The professor has been spearheading research on Wolf 1061, a solar system in the Milky Way galaxy approximately 14 light-years away from our own system, according to Kane.

Miranda Waters, an astronomy major who graduated in December and one of Kanes former assistants, initially introduced the Wolf 1061 system to his corpus of research.

Waters thought the system orbited by three planets was odd and brought Kanes attention to it. According to the alumna, their team jumped right in to help find out more, and was able to get additional help from outside sources, such as Tennessee State University, to aid in research.

We had great tools at our disposal, like telescopes in Tennessee and Arizona, Waters said.

Along with the help of several other SF State graduate and undergraduate students, Kane and his research assistants then submitted their newest research paper entitled, Characterization of the Wolf 1061 Planetary System, to the Cornell University Astrophysics Journal, which explored the new findings on the system that houses three different planets.

The paper, which was also written and revised by contributors Kasper von Braun, Gregory Henry, Tabetha Boyajian and Andrew Mann, examined Wolf 1061s habitable zone conditions, according to the same University press release.

Habitability is exciting because its talking about if the planet is small in size like the Earth, does it have a rocky surface, could it have an atmosphere that could support life and does it have the right temperatures? Kane explained. And thats what we call a habitable zone around a star, where it [the planet] could still have liquid water on its surface.

According to the research, planets in the Wolf 1061 system have a rocky, or terrestrial, surface and one of the three planets sits right on the edge of the habitable zone both are potentially habitable characteristics.

1061c (the planet in the middle of the system) is at the right distance, its right on the inner edge of the habitable zone, where you could have liquid water, Kane said.

However, according to Kane, many more elements of a planet need to be explored in order to determine if any form of life could exist.

There are a lot of pieces that go together to see if its [the system] habitable or not, Kane said. So the smoking gun for any planet is to be able to measure the composition of its atmosphere in order to look for biological activity that is influencing the atmosphere.

Levels of oxygen from plant photosynthesis and methane excrements from animals like cows are signs of biological activity that would affect atmosphere, according to Kane.

Once the newest NASA James Webb space telescope is launched, Kane and his team should be able to extend their research to measure the atmospheric density of the planets in the system.

The James Webb telescope has been in the works for the past 10 years and is due to launch in early 2018, which could help, Waters explained. Right now were just using our imagination to see what these worlds could look like.

According to Waters, the most rewarding thing about studying and researching exoplanets is the idea of being able to see into the recesses of our galaxy.

I honestly think it is just amazing to see whats out there in the neighborhood and wondering if we are alone, Waters said.

Maarten Golterman, former Department of Physics and Astronomy chair, said that many students in the program are taking great interest in Kanes work and that it is certainly inspirational for the students.

Exoplanets appeal to the public imagination, because there may be other planets out there like ours, Gloterman said.

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SF State astronomy professor looks for habitable planets 14 light years away - Golden Gate Xpress

(Courtesy: Foundation for Apalachian Ohio)

An observatory and astronomy park dedicated to John Glenn is planned to be built at Hocking Hills.

The Friends of Hocking Hills State Park and the Columbus Astronomical Society started planning the John Glenn Astronomy Park back in 2016.

With the passing of John Glenn, the park has seen an increase in funding. As of this writing, the park has received 60 percent of their $1.6 million funding goal.

Per the Columbus based M+A Architects blog post by project coordinator Lucia Hoehne, the site of the park is elevated enough for the telescope to be above the fog that collects on the ground.

The park will serve as an educational, recreational and research-oriented astronomy center featuring sundials, openings to mark solstices and equinoxes by sunlight, seating for lectures, and fields for telescopes and stargazing.

The observatory will house a large telescope for planetary nebulas, globular clusters, and galaxies. A second telescope will be used for astrophotography. Also, a small solar telescope will able to be taken to the plaza for public demonstrations.

The Friends of Hocking Hills State Park says that construction will start in the spring of 2017 and is expected to be completed by the end of 2017.

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Astronomy park dedicated to John Glenn planned for Hocking Hills - ABC6OnYourSide.com

The supermassive black holes found at the centers of galaxies are known for their extreme X-ray emission. This emission is associated with the massive hot disks of gas and debris that circle these monstrous black holes before it is consumed.

However, X-ray observations of distant galaxies have also uncovered additional luminous X-ray sources that arent associated with the galactic centers (where supermassive black holes are found). These are ULXs, or ultraluminous X-ray sources. ULXs have been traditionally explained as large stellar-sized (80-100 solar masses) or possibly intermediate mass (1,000-100,000 solar masses) black holes accreting material at high rates. Now, one famous ULX has been identified not as a black hole, but as a neutron star with a mass less than 1.5 that of our Sun, exhibiting a complex and powerful magnetic field.

Gian Luca Israel, a researcher at the Italian National Institute for Astrophysics, and his colleagues used observations from the X-ray Multi-Mirror Mission (XMM-Newton) and Nuclear Spectroscopic Telescope Array (NuSTAR) space telescopes to delve deeper into the inner workings of ULX-1 in NGC 5907, a ULX located 40 million light-years away in the edge-on spiral galaxy NGC 5907, often called the Knife Edge or Splinter Galaxy.

Within these observations, Israel and his team identified periodic variations in the X-rays coming from this object, which theyve now identified as a pulsar (a spinning neutron star). Furthermore, this pulsar is accreting material at such high rates that its spinning up, dramatically increasing the speed at which it rotates around its axis. They measured the pulsars period as 1.43 seconds in 2003, while observations made in 2014 clocked the pulsar at a faster rotation rate of 1.13 seconds. In a video accompanying the announcement, Israel compared this speed-up to the Earths day growing shorter by 5 hours in just 11 years.

The pulsar is both the farthest and brightest X-ray pulsar detected to date. Its intense radiation can only be explained by the presence of an extremely strong multipolar magnetic field, such as the type of magnetic field found in magnetars. A magnetar is a type of neutron star with a magnetic field measuring a quadrillion times that of Earths magnetic field (which, by the way, is dipolar, not multipolar). The magnetic field of the average (non-magnetar) neutron star is about a trillion times as strong as Earths.

Why is this determination so incredible? The luminosity of a black hole (or any stellar-type object) is limited by physics. Because photons can actually exert pressure on their surroundings, photons above a certain energy would overpower the force of gravity exerted by the mass of the star or black hole, disrupting an accretion disk and essentially turning off the source of its X-rays. This energy limit is called the Eddington limit, and its dependent on the mass of an object, and larger objects have larger Eddington limits. ULXs are objects that arent supermassive black holes, but are seen exceeding this Eddington limit for neutron stars and even normal stellar-sized black holes. The fact that theyre radiating above this limit, then, is a conundrum.

However, there is a catch to this argument. The Eddington limit assumes that an object is radiating isotropically in all directions. But pulsars are neutron stars that emit from only a very small area, beaming their intense radiation out into space in coherent beams like a lighthouse. These observations of periodicity in the X-ray emission and the determination that ULX-1 is a neutron star with a multipole magnetic field help to explain why this objects radiation exceeds the accepted Eddington limit of a neutron star by 1,000 times. Such a beaming effect would lower the true intrinsic luminosity of the source, and thus its mass, making the explanation of at least some ULXs as neutron stars within the realm of possibility.

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The brightest, most distant pulsar has a complex and powerful ... - Astronomy Magazine

A University of Cambridge-led team of astronomers, using chemical elements as a proxy for stellar DNA, has assembled an evolutionary family tree of stars in the solar neighborhood.

Phylogenetic tree of 22 solar twins in the solar neighborhood, created using 17 elemental abundances. Stellar populations are assigned considering the age and the dynamical properties of the stars and are indicated at the right. Branch lengths have units in dex, with the scale indicated at the left bottom. The background image shows the Carina Nebula, a region of massive star formation in the southern skies. Image credit: Jofre et al, doi: 10.1093/mnras/stx075 / ESO / T. Preibisch.

In evolution, organisms are linked together by a pattern of descent with modification as they evolve.

Stars are very different from living organisms, but they still have a history of shared descent as they are formed from gas clouds, and carry that history in their chemical structure.

By applying the same phylogenetic methods that biologists use to trace descent in plants and animals it is possible to explore the evolution of stars.

Writing in the Monthly Notices of the Royal Astronomical Society (arXiv.org preprint), University of Cambridge astronomer Paula Jofre and co-authors describe how they set about creating a phylogenetic tree of life that connects a number of solar neighborhood stars.

In 1859, Charles Darwin published his revolutionary view of life, claiming that all organic beings that have ever lived have descended from one primordial form, the astronomers explained.

One important outcome of Darwins view of descent with modification was the recognition that there is a tree of life or phylogeny that connects all forms of life.

The key assumption in applying a phylogenetic approach is that there is continuity from one generation to the next, with change occurring from ancestral to descendant forms. This assumption is also applicable to stars in galaxies, even if the mechanisms of descent are very different.

The use of algorithms to identify families of stars is a science that is constantly under development, Dr. Jofre added.

Phylogenetic trees add an extra dimension to our endeavors which is why this approach is so special. The branches of the tree serve to inform us about the stars shared history.

Dr. Jofre and her colleagues from the universities of Cambridge and Oxford picked 22 stars, including the Sun, to study.

The oldest star in the sample, HD 220507, is estimated to be 9.8 billion years old, which is twice as old as the Sun. The youngest, HD 96116, is 700 million years old.

The chemical elements were measured from data coming from ground-based high-resolution spectra taken with large telescopes located in the north of Chile.

Once the families were identified using the chemical DNA, their evolution was studied with the help of their ages and kinematical properties obtained from ESAs Hipparcos mission.

Three main stellar populations, i.e. groups of stars sharing a common ancestor, were identified, the astronomers said.

The first one, includes the following stars: the Sun, HD 2071, HD 45184, HD 146233, HD 8406, HD 92719, HD 27063, HD 96116 and HD 134664.

A second stellar population includes the stars: HD 210918, HD 45289 and HD 220507.

A third stellar population appears to be equally independent from the other two populations, and includes the stars HD 78429, HD 208704, HD 20782 and HD 38277.

Finally, six stars HD 28471, HD 96423, HD 71334, HD 222582, HD 88084 and HD 183658 can not be assigned to any population with enough statistical confidence.

We wanted to show that it is possible to apply phylogenetic analyses and tree thinking in the field of Galactic archaeology, the scientists said.

In biology it is commonly said that to study evolution, one essentially analyses trees. Galactic archaeology should be no different, especially now, during its golden ages.

The difference between stars and animals is immense, but they share the property of changing over time, and so both can be analyzed by building trees of their history, added University of Cambridge Professor Robert Foley, co-author of the study.

_____

Paula Jofr et al. 2017. Cosmic phylogeny: reconstructing the chemical history of the solar neighbourhood with an evolutionary tree. Mon Not R Astron Soc 467 (1): 1140-1153; doi: 10.1093/mnras/stx075

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Astronomers Reconstruct History of Solar Neighborhood with Evolutionary Tree - Sci-News.com

An astronomy park dedicated to the late U.S. Senator and astronaut was in the making almost two years before his passing last December. Now, the site will serve as a tribute by inspiring future generations of night sky gazers and explorers.

An organizer of the project, Omie Warner, says their efforts have received added support since Glenn's passing. Private donors have raised about 60 percent of their $1.6 million goal, allowing them to begin construction early this spring. Warner says the park will be completed by October or November.

Set in the wilderness of the Hocking Hills, the public park will include space for stargazing and eventually a telescope for Ohio State University researchers.

OSU astrophysicist Paul Sutter says Hocking Hills State Park is relatively free of light pollution and is in one of the darkest parts of Ohio.

If you want to see the night sky as it really is, says Sutter, this is your best bet.

"And so to have a park there, an observatory there, it makes perfect sense," Sutter says.

Sutter says he hopes to have the site designated as a dark sky preserve. In the same way a wild life refuge protects animals, this designation ensures surrounding developments don't drown out the night sky with light pollution.

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In Memory Of John Glenn, An Astronomy Park Takes Shape - WOSU

Artists concept of the Juno spacecraft at Jupiter. Credit: NASA/JPL-Caltech

Concerns about the health of the Juno spacecrafts main engine have compelled NASA managers to keep the research probe in its current arcing, high-altitude orbit around Jupiter, a decision that will delay the full science return from the $1.1 billion mission but should still allow it to meet all predetermined objectives.

Juno fired its main engine to brake into orbit around Jupiter on July 4, 2016, maneuvering into an egg-shaped 53-day orbit that takes the spacecraft several million miles from the giant planet on each circuit.

At the low end of the orbit, the spacecraft passes within 3,000 miles (5,000 kilometres) from Jupiters cloud tops, permitting Junos instruments to peer deep into the atmosphere, measure the planets extreme magnetic field and radiation belts, observe its auroras, and take the first detailed images of its poles.

But engineers called off another engine burn planned for Oct. 19 to put Juno in a tighter 14-day orbit, the science perch envisioned by mission managers since the projects inception.Most of Junos scientific observations occur when the probe is closer to the planet, and the 14-day orbit was designed to give researchers rapid-fire data returns during close approaches every two weeks.

Ground controllers noticed two helium check valves inside the spacecrafts main propulsion system did not behave as expected during pressurization of Junos propellant tanks about a week before the planned Oct. 19 engine firing. The valves opened in several seconds before previous engine burns, but took several minutes to open in October.

Rick Nybakken, Junos project manager at NASAs Jet Propulsion Laboratory, told Spaceflight Now that engineers recommended canceling the maneuver and keeping the craft in its current 53-day orbit after a multi-month investigation.

The project recommended not doing the burn, Nybakken said in a Feb. 17 interview. Were in a great science orbit, the spacecraft is healthy, the instruments are healthy. Were getting incredible science, and its teaching us more about Jupiter, and there are a lot of very interesting surprises about Jupiter, so we recommended not to take any additional risk that might jeopardize that not to do this burn and ultimately NASA Headquarters agreed with that recommendation.

According to Nybakken, experts considered an option in which Junos Leros 1b main engine, designed and built by Moog-ISP in the United Kingdom, could have fired in a backup blow-down mode using residual tank pressure, bypassing the suspect check valves. In a normal burn, the check valves would actuate to regulate pressure in the propellant system feeding the thruster.

Officials decided the risk of doing a blow-down burn was too great, Nybakken said. Any problem during such an engine firing could have stranded Juno midway between the 53-day and 14-day orbits in a less optimal perch for science observations.

In the 53-day orbit, Juno will avoid flying through Jupiters shadow, keeping the crafts power-generating solar panels in sunlight. If Juno ended up in an unplanned lower orbit because of a sub-optimal engine burn, the probe would have flown through a series of eclipses in 2019, starving it of sunlight and likely ending the mission.

The choice not to execute the orbit-lowering burn preserves the option to use Junos smaller maneuvering thrusters to steer clear of Jupiters shadow and keep the mission going beyond 2019.

It wasnt so much that the risk was unacceptable, its just that if anything off-nominal were to happen, you bring in these mission-ending eclipses in 2019, Nybakken said. In our current orbit, the size of the orbit is large enough, and the time of the orbit helps give us the operational latitude to avoid those eclipses.

Nybakken said the inquiry into Junos propulsion woes did not determine a root cause for the sticky valves. Officials quickly decided against using the valves for a regulated burn, and instead studied the backup blow-down option before eventually concluding Junos orbit should not be lowered at all.

At a high level, one of the leading theories is that we can have a very low level of interaction at the vapor level between fuel and oxidizer, and it can create products that can interfere with proper valve operation, Nybakken said. Beyond that, it is kind of to be determined. We didnt require root cause to realize the valves are not working as intended.

Engineers ruled out any link between Junos propulsion problem and engine failures on two geostationary communications satellites last year, Nybakken said.

The commercial Intelsat 33e and the U.S. Navys MUOS 5 communications satellites were to use on-board engines to raise their orbits to geostationary altitude 22,300 miles (35,800 kilometres) above Earths equator after launching in June and August 2016. Both satellites had to use backup thrusters to finish the job.

Nybakken said those engine failures were unrelated to the issue aboard Juno, and engineers with JPL and Lockheed Martin Junos prime contractor cleared the Leros 1b engine on the Jupiter orbiter in October, before encountering the sticky check valves.

There were a couple of failures last fall that we looked into, and we were able to determine that those failures did not represent any sort of increased risk to Juno, Nybakken said. And after we completed that investigation, we were, in fact, planning to go ahead with this maneuver.

One benefit of Junos predicament is the higher 53-day orbit will keep the spacecraft away from the worst of Jupiters intense radiation belts, which harbour hazards that mission designers believed would limit the missions duration to some time in 2018.

It turns out in the 53-day orbits, we cross the equator, where the radiation belts are, much farther out, so we have much less radiation dose, Nybakken said. Of course, with the orbits being larger, the dose as a function of time is much slower as well.

Junos next close pass by Jupiter is set for March 27, completing its fifth orbit of the planet since last years arrival.

Juno is healthy, its science instruments are fully operational, and the data and images weve received are nothing short of amazing, said Thomas Zurbuchen, associate administrator for NASAs science mission directorate in Washington, in a statement. The decision to forego the burn is the right thing to do preserving a valuable asset so that Juno can continue its exciting journey of discovery.

The Juno mission is funded through July 2018, for a total of 12 science orbits, down from the 32 science orbits originally planned, NASA said in a statement.

Junos science team can then propose to continue the mission for another two years as part of NASAs senior review process, in which a panel of independent researchers recommend to the agency which of its planetary science missions should continue to receive federal funding.

Juno is providing spectacular results, and we are rewriting our ideas of how giant planets work, said Scott Bolton, the missions principal investigator from the Southwest Research Institute in San Antonio. The science will be just as spectacular as with our original plan.

Were very excited about what weve seen so far, and every time we fly by the planet its like Christmas time, Nybakken said. The data is stunning.

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Follow Stephen Clark on Twitter: @StephenClark1.

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NASA's Juno spacecraft to remain in current orbit around Jupiter - Astronomy Now Online