Category Archives: Astronomy

According to the new data, the Milky Way was once what astronomers call a starburst galaxy. Its an area commonly seen in other parts of the universe where stars form at a fast rate. About 80 percent of the stars in the center of the Milky Way were formed between 8 billion and 13.5 billion years ago. But about 1 billion years ago, another intense star-formation burst happened, creating many massive new stars. These large stars live shorter lives than small stars. And when large stars die, they explode. So the starburst led to a surge in supernovae and a dramatic period of star formation all at around the same time.

This burst of activity, which must have resulted in the explosion of more than 100,000 supernovae, was probably one of the most energetic events in the whole history of the Milky Way, said researcher Francisco Nogueras-Lara in a press release.

The new data also throw out the old theory that all stars were formed at around the same time.

The study was published in Nature Astronomy.

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When the Milky Way erupted in 100000 supernovae - Astronomy Magazine

In the course of conducting solar astronomy, scientists have noticed that periodically, the Suns tangled magnetic field lines will snap and then realign. This process is known as magnetic reconnection, where the magnetic topology of a body is rearranged and magnetic energy is converted into kinetic energy, thermal energy, and particle acceleration.

However, while observing the Sun, a team of Indian astronomers recently witnessed something unprecedented a magnetic reconnection that was triggered by a nearby eruption. This observation has confirmed a decade-old theory about magnetic reconnections and external drivers, and could also lead to a revolution in our understanding of space weather and controlled fusion and plasma experiments.

The team responsible for the discovery was led by Abhishek Srivastava, a solar scientist from the Indian Institute of Technology (BHU), and included astronomers from the University of South Bohemia, the School of Earth and Space Sciences at Peking University, Centre for mathematical Plasma Astrophysics, the Indian Institute of Astrophysics, and the Armagh Observatory.

Using data from NASAs Solar Dynamics Observatory, Srivastava and his colleagues observed a magnetic explosion unlike any other. It began in the upper reaches of the Suns atmosphere (the corona), where a large loop of material (aka. a prominence) was launched by an eruption from the Suns surface. This loop then began descending back to the surface, but then ran into a mass of entangled field lines, triggering a magnetic explosion.

As Abhishek Srivastava, a solar scientist from the Indian Institute of Technology (BHU), explained:

This was the first observation of an external driver of magnetic reconnection. This could be very useful for understanding other systems. For example, Earths and planetary magnetospheres, other magnetized plasma sources, including experiments at laboratory scales where plasma is highly diffusive and very hard to control.

In previous cases, magnetic reconnections that were observed on both the Sun and around Earth had been spontaneous in nature. These occur only when conditions are just right in a particular region of the Sun, which includes a thin sheet of ionized gas (aka. plasma) that only conducts electric current but only weakly.

While the possibility of forced reconnections driven by explosions was first theorized 15 years ago, none had ever been seen directly. This type of reconnection can happen in a wider range of places where plasma sheets have even lower resistance to conducting electric current. However, it also requires an eruption to trigger it, which will squeeze the plasma and magnetic fields and cause them to reconnect.

Using the SDO, the team was able to study this plasma by examining the Sun at a wavelength that showed particles heated to between 1 2 million C (1.8 3.6 million F). This allowed them to observe and take images of a forced reconnection event in the solar corona for the first time in history. It began with the prominence in the corona falling back into the photosphere, where it ran into a mess of field lines and reconnected in a distinctive X-shape.

Magnetic reconnections offer a possible explanation for why the Suns corona is actually millions of degrees hotter than the lower atmosphere which has been an enduring mystery for astronomers. To address this, solar scientists have spent decades looking for a possible mechanism that could be responsible for driving this heat.

With this in mind, Srivastava and his team observed the plasma in multiple ultraviolet wavelengths to calculate its temperature after the reconnection event. The data showed that the prominence, which was cooler than the surrounding corona, became hotter after the reconnection event. This suggests that forced reconnection could be responsible for heating the corona locally.

While spontaneous reconnection could still be a contributing factor, forced reconnections appear to be a bigger one, capable of raising plasma temperatures faster, higher, and in a more controlled fashion. In the meantime, Srivastava and his colleagues will continue to look for more forced reconnection events in the hopes of better understanding the mechanics behind them and how often they might happen.

These results could also lead to additional solar research to see if eruption events like flares and coronal mass ejections could also cause forced reconnection. Since these eruptions are the driving force behind space weather, which can wreak havoc on satellites and electronic infrastructure here on Earth, further research into forced reconnection could help lead to better predictive models

These, in turn, would allow for early warnings and preemptive measures to be taken in the event of a flare or ejection. Understanding how magnetic reconnection can be forced by an external driver could also lead to breakthroughs in the lab. This is particularly true of fusion experiments, where scientists are working to figure out how to control streams of super-heated plasma.

Credit: NASA, The Astrophysical Journal

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Astronomers Discovered a New Kind of Explosion That the Sun Can Do - Universe Today

Dean Regas, Special to Cincinnati Enquirer Published 11:53 a.m. ET Dec. 23, 2019 | Updated 12:02 p.m. ET Dec. 23, 2019

The planet Venus, left, and the crescent moon form a striking pair in the sky.(Photo: AP file)

In 2019, astronomers captured the first picture of a black hole, the world celebrated the 50th anniversary of the moon landingand Mercury crossed in front of the sun for the last time until 2032.What out-of-this-world occurrences will be happening in the universe next year?Here are the cant-miss astronomical events of 2020.

Maybe youve seen it already: the planet Venus is blazing in the southwestern sky just after dark.Venus shines brighter than any other star and may even make you think a UFO is about to land its that suspiciously bright.

Venus will be visible just after sunset every night until May and the best nights to catch this planet are when the crescent moon stands nearby.These Venus-moon conjunctions will occur on the evenings of Jan.27 and 28, Feb.27, March 27 and 28, April 26, and finish up on May 23 and 24.No telescope needed: These picturesque pairings of the Moon and Venus amid the afterglow of sunset are best observed with the naked eye.

Pluto as seen by the New Horizons spacecraft, which carried a small portion of the ashes of discoverer Clyde Tombaugh.(Photo: Associated Press)

On Feb.18, 1930, American astronomer Clyde Tombaugh made a momentous discovery.By comparing two pictures taken at different times, he saw a tiny dot move through space.That was Pluto, and Tombaughs discovery turns 90 this year.Pluto was considered a planet until 2006 when it was infamously demoted to dwarf planet status, but in 2015, the unmanned New Horizons spacecraft flew by this tiny, icy world and gave Pluto fans close up images from the far reaches of the solar system.

Fun fact: The average temperature on Mars is minus 81-degrees Fahrenheit, according to NASA. The average temperature on earth is 57-degrees.(Photo: Andrei Lacatusu)

The Red Planet is back in 2020.Mars, always a crowd favorite, returns to the evening sky in the fall when it will appear as a bright, orange beacon in the night sky.The night of closest approach will be Oct.6, but you will have plenty of time to get to know Mars. It will shine brightly every night from September 2020 to early 2021.

There will be a full moon on Halloween night in 2020.(Photo: The Enquirer/Michael E. Keating)

Perhaps the biggest astronomical story of 2020 will occur on Halloween night.Not only is Oct.31 a Saturday this year, but it will also be the night of a full moon.But wait, theres more. Since this will be the second full moon of October (there will be one on Oct. 1), it will also be considered a Blue Moon.The moon wont actually turn blue, but for backyard stargazers and trick-or-treaters this will make a great backdrop to the holiday and is sure to fuel internet superstitions.

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There will be a whopping four lunar eclipses and two solar eclipses in 2020, but none of them are good for viewers in the United States or Canada.The lunar eclipses on Jan.10, June 5, July 5and Nov.30 are all penumbral eclipses, meaning the moon enters a fainter shadow of the Earth and is not noticeable to the average viewer.The solar eclipse on June 21 is only visible from the Eastern Hemisphere and the total solar eclipse on Dec.14 is only visible from Chile and Argentina.So plan some trips and chase eclipses all year long.

Head to Cincinnati Observatory in 2020 for a new look at the night.(Photo: Leigh Taylor, Enquirer/Leigh Taylor)

The two largest planets in the solar system, Jupiter and Saturn will be visible all summer and fall of 2020.Although they are hundreds of millions of miles apart, each night, they will appear closer together in our skies. The best alignment will be on Dec.21, when Jupiter and Saturn will seem so close together in the sky that they will almost touch. This Jupiter-Saturn conjunction only happens every 20 years, but this is an exceptionally close pairing. If you aim a telescope at them that evening, it may be the only time in your life where you can see the surface of Jupiter and the rings of Saturn at the same time.

Heres hoping for a lot of clear skies in 2020 so you dont miss even one exciting event in the sky.

Dean Regas is the Astronomer for the Cincinnati Observatory, and author of the books 100 Things to See in the Night Sky and Facts from Space! He can be reached at dean@cincinnatiobservatory.org

Where: Cincinnati Observatory

What: Three-night astronomy course. Perfect for beginners who want to learn more about observing the night sky.

When: Tuesday, Jan.7, 14, and 21, from 7-9 p.m.

Admission: $50 per person for the series, $40 per Observatory member

Information: Reservations required by calling 513-321-5186 or online at http://www.cincinnatiobservatory.org.

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Keep your eye on the sky: Astronomical highlights of 2020 - The Cincinnati Enquirer

Any number of scientific discoveries or events make the "best of" lists every year. Well, our astronomy contributor Jean Creighton is no different, and she shares her picks for 2019:

Lake Effect's Bonnie North speaks with astronomy contributor Jean Creighton.

First all-female spacewalk

The first all-female spacewalk took place on Oct. 18. Astronauts Christina Koch and Jessica Meir made the historic excursion.

The initial all-female spacewalk was planned in March, but it was canceled.

"What's interesting here is that the reason why the original crew didn't get to do it was because they didn't have a suit that was suitable for two women at the same time," Creighton explains.

As NASA makes new missions to the Moon and possibly even Mars, she says spacesuits will need to be made individually for each astronaut.

"Because people are going to be spending a lot of time in space, they're going to have suits that will be made to their particular size men or women," she says.

First molecule in the universe

Now, we go from a huge spacewalk to something that's very, very, very small. After decades of searching, scientists discovered the first molecule that formed in the universe. Keep in mind, the universe is almost 14 billion years old.

Scientists believe the universe's first type of molecule is helium hydride. It's a combination of helium and hydrogen, according to NASA, and likely formed 100,000 years after the Big Bang.

"That was made in the lab in 1925, almost 100 years ago. But it was elusive. We couldn't identify it in any of the astronomical objects that we've been looking at," Creighton says.

But finally, a NASA aircraft called SOFIA (Stratospheric Observatory for Infrared Astronomy) made it possible for scientists to see helium hydride for the first time.

First photograph of a supermassive black hole

"We have been lucky in the black hole department for the last few years. This year, it was a direct image of a supermassive black hole at the center of very cool galaxy, which is called M87," says Creighton.

She says what's cool about M87 is that way before the photograph, scientists were able to see "huge lobes." Since the lobes were much larger than the galaxy, scientists were curious about how the lobes were powered.

"It turns out, at the core, as we now understand of most galaxies, of M87 there is a supermassive black hole that as it spins, it ejects sharp jets that pile into the gas and make these balloons of gas at the intersection of where the jet hits and where clouds of material might be," she explains.

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What Cool Things Happened In Astronomy In 2019 - WUWM

When stars exhaust their supply of fuel, they collapse under their own weight and explode, blowing off their outer layers in an event known as a supernova. In some cases, these events leave behind neutron stars, the smallest and densest of stellar objects (with the exception of certain theoretical stars) that sometimes spin rapidly. Pulsars, a class of neutron star, can spin up to several hundred times per second.

One such object, designated J0030+0451 (J0030), is located about 1,100 light-years from Earth in the Pisces constellation. Recently, scientists using NASAs Neutron star Interior Composition Explorer (NICER) were able to measure the pulsars size and mass. In the process, they also managed to locate the various hot spots on its surface, effectively creating the first map of a neutron star.

Since 2017, NICER has been conducting observations from the International Space Station (ISS) for the purpose of creating of learning what goes on inside a neutron star. In addition to providing high-precision measurements of neutron stars and other super-dense objects, the data it collects will also be used to create an X-ray map of the cosmos and to test pulsars as a possible navigation beacon.

As Paul Hertz, the director of NASAs astrophysics division, said in a recent NASA press release:

From its perch on the space station, NICER is revolutionizing our understanding of pulsars. Pulsars were discovered more than 50 years ago as beacons of stars that have collapsed into dense cores, behaving unlike anything we see on Earth. With NICER we can probe the nature of these dense remnants in ways that seemed impossible until now.

For decades, scientists have been studying pulsars in the hopes of getting a better understanding of their inner workings. According to the simplest model, pulsars have incredibly powerful magnetic fields shaped like a dipole magnet. Combined with the pulsars rotation, this causes particles from its surface to be focused into tight beams emitted from the poles. This creates a strong strobing effect that resembles a lighthouse to observers.

This effect leads to variations in the pulsars brightness (in the X-ray wavelength), which astronomers have observed in the past. At the same time, astronomers have also observed hotspots on the surface of pulsars, which are the result of their magnetic fields ripping particles from the surface and accreting them around the poles. While the entire surface glows brightly in X-rays, these hot spots glow brighter.

However, the new NICER studies of J0030 (a millisecond pulsar that revolves 205 times per second) showed that pulsars arent that simple. Using NICER data obtained from July 2017 to December 2018, two groups of scientists mapped out the hotspots on J0030 and came to similar conclusions about its mass and size.

The first team was led by Thomas Riley and his supervisor Anna Watts, a doctoral student in computational astrophysics and a professor of astrophysics (respectively) at the University of Amsterdam. To recreate the X-ray signals they observed, Riley and his colleagues conducted simulations of overlapping circles of different sizes and temperatures using the Dutch national supercomputer Cartesius.

In addition to determining that J0030 is around 1.3 Solar masses and 25.4 km (15.8 mi) wide, they identified two hot spots one small and circular, the other long and crescent-shaped. The second team, led by astronomy professor Cole Miller of the University of Maryland, conducted similar simulations using UMDs Deepthought2 supercomputer.

They found that J0030 is 1.4 Solar masses, measures 26 km (16.2 mi) wide, and came up with two solutions for hotspots. In the first, they identified two possible hotspots, one of which has two ovals that closely matches the results of Rileys team. In the second, they found a possible third hotspot located around the pulsars southern rotational pole.

As Riley explained, these results revealed a great deal about J0030 and other pulsars:

When we first started working on J0030, our understanding of how to simulate pulsars was incomplete, and it still is. But thanks to NICERs detailed data, open-source tools, high-performance computers and great teamwork, we now have a framework for developing more realistic models of these objects.

As predicted by Einsteins General Theory of Relativity, a pulsar is so dense that its gravity warps the very fabric of space-time around it. The effect is so pronounced that light coming from the side facing away from the observer is bent and redirected towards them. This makes the star look bigger than it really is and means that hot spots dont disappear entirely when they rotate away from the observer.

Thanks to NICERs precision, which is about 20 times that of previous instruments, astronomers are able to measure the arrival of each X-ray from a pulsar to better than a hundred nanoseconds. From Earth, the two teams had a clear view of J0030s northern hemisphere and expected to find one hotspot there. Instead, they identified up to three, all of which were located in the southern hemisphere.

As Miller explained, these observations would not have been possible without NICERs precision:

NICERs unparalleled X-ray measurements allowed us to make the most precise and reliable calculations of a pulsars size to date, with an uncertainty of less than 10%. The whole NICER team has made an important contribution to fundamental physics that is impossible to probe in terrestrial laboratories.

This constitutes the first case of astronomers mapping out the surface of a pulsar, and the results indicate that their magnetic fields are more complicated than the traditional dipole model would suggest. While scientists have yet to determine why J0030s spots are arranged and shaped the way they are, these findings indicate that these answers could be within reach.

Even more impressive is the fact that two teams arrived at similar findings independently of one another. As Zaven Arzoumanian, the NICER science lead at NASAs Goddard Space Flight Center, expressed:

Its remarkable, and also very reassuring, that the two teams achieved such similar sizes, masses and hot spot patterns for J0030 using different modeling approaches. It tells us NICER is on the right path to help us answer an enduring question in astrophysics: What form does matter take in the ultra-dense cores of neutron stars?

As part of the Astrophysics Mission of Opportunity element of NASAs Explorers program, NICERs main scientific objective is to precisely measure the size and mass of several pulsars. This information will yield valuable clues as to what transpires within their interiors, where matter is compressed to densities that are impossible to simulate in laboratories here on Earth.

This information will also help advance astronomers understanding of black holes and other super-dense objects. The analysis of the NICER observations of J0030 has already led to a series of papers that are featured in a focus issue of The Astrophysical Journal Letters.

Be sure to check out this video that explains the researchers findings as well, courtesy of the NASA Goddard:

Further Reading: NASA

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Astronomers Map the Surface of a Pulsar - Universe Today

A team of astronomers has produced a new image of an arc-shaped object in the center of our Milky Way galaxy. The feature, which resembles a candy cane, is a magnetic structure that covers an enormous region of some 160 light-years. A light-year is the distance light travels in one year almost 6 trillion miles.

Mark Morris, a UCLA professor of physics and astronomy and a member of the research team, discovered the structure, also called the radio arc,with a former student, Farhad Yusef-Zadeh, back in 1983, but they did not have such a complete and colorful image of it then.

The new image shows the inner part of our galaxy, which houses the largest, densest collection of giant molecular clouds in the Milky Way. These vast, cool clouds contain enough dense gas and dust to form tens of millions of stars like the sun, Morris said.

In the image, blue and greenish-blue features reveal cold dust in molecular clouds where star formation is still in its infancy. Yellow features reveal the presence of ionized gas and showwherehundreds of massive stars have recently formed. Red and orange regions show areas where high-energy electrons emit radiation by a process called synchrotron emission, such as in theradio arcand Sagittarius A, the bright source at thegalaxys center that hosts its supermassive black hole.

Many of the universes secrets are being revealed through theparts of the electromagnetic spectrum of light that are not visible to the human eye. The electromagnetic spectrum encompasses the complete range of light seen and unseen from gamma rays, X-rays and ultraviolet light on one end to infrared and radio waves on the other. In the middle is the small visible spectrum that includes the colors humans can detect with the unaided eye. Gamma rays have wavelengths billions of times smaller than those of visible light, while radio waves have wavelengths billions of times longer than those of visible light. Astronomers use the entire electromagnetic spectrum. In the study that led to the new image, the research team observed radio waves with a wavelength of 2 millimeters.

The candy cane is a magnetic feature in which we can literally see the magnetic field lines illuminated by the radio emission, Morris said. The new result revealed by this image is that one of the filaments is inferred to contain extremely high-energy electrons, the origin of which remains an interesting and unsettled issue.

The candy cane arc is part of a set of radio-emitting filaments extending 160 light-years. It ismore than 100 light-years away from the central supermassive black hole. However, inanother study recently, Morris and colleagues saw similar magnetic radio filaments that they believe are connected to the supermassive black hole, which may lead to important new ways to study black holes, he said.

To produce the new image, the astronomers used a NASA 2-millimeter camera instrument called GISMO, along with a 30-meter radio telescope located at Pico Veleta, Spain. They also took archival observations from the European Space AgencysHerschel satelliteto model the infrared glow of cold dust. They added infrared data from theSCUBA-2instrument at theJames Clerk Maxwell Telescopenear the summit of Maunakea, Hawaii, and radio observations from the National Science FoundationsVery Large Array, located near Socorro, New Mexico.

The teams research describing the composite image was published last month in Astrophysical Journal.

Morris research interests include the center of the Milky Way, star formation, massive stellar clusters, and red giant stars, which are dying stars in the last stages of stellar evolution.

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Astronomers reveal new image of candy cane-shaped feature in the center of our galaxy - UCLA Newsroom

Thursday, November 28Although the Moon passed between the Sun and Earth just two days ago, its rapid orbital motion has already brought it back into view low in the southwest shortly after sunset. As a bonus, the slender crescent appears against the azure twilight in the company of Venus and Jupiter. You can find brilliant Venus 2 below the Moon and dimmer Jupiter 6 to Lunas lower right.

Mercury is now in the midst of its finest morning apparition of 2019. The planet reaches greatest elongation from the Sun today, lying 20 west of our star and appearing 10 high in the east-southeast 45 minutes before sunrise. Mercury maintains this altitude for the next two days. The inner world shines at magnitude 0.6, which is easily bright enough to see with your naked eye, though binoculars will help you pick it out of the twilight glow. When viewed through a telescope, Mercurys 7"-diameter disk appears slightly more than half-lit.

Friday, November 29The waxing crescent Moon appears 2 to Saturns left this evening. The two stand some 15 above the southwestern horizon an hour after sunset and will make a pretty pair with the naked eye or through binoculars. Of course, Saturn makes a tempting target any night this week. The ringed world shines at magnitude 0.6, more than a full magnitude brighter than any of the background stars in its host constellation, Sagittarius. The best views come through a telescope, however, which reveals a 15"-diameter globe surrounded by a spectacular ring system that spans 35" and tilts 24 to our line of sight.

Although Thanksgiving weekend signifies autumn to many people, the stars of both summer and winter appear prominent in late Novembers evening sky. If you head out around 9 p.m. local time and look toward the west, youll see the bright stars of the Summer Triangle. These three luminaries Vega, Deneb, and Altair stand out nicely. Deneb appears highest (nearly halfway to the zenith), while the brightest, Vega, lies lower in the northwest. Now, if you turn around and face east, youll find stars normally associated with winter. Betelgeuse, Rigel, Aldebaran, and Capella all clear the horizon before 8 p.m. and appear conspicuous an hour later.

Saturday, November 30While the stars of summer and winter remain on view these late November evenings, the stars of spring are not so lucky. The Big Dipper swings low in the north at this time of year. Although this conspicuous asterism never sets from much of the United States and Canada, it does come close. And the star at the end of the handle magnitude 1.9 Eta () Ursae Majoris does dip below the horizon around 9 p.m. local time for viewers south of 40 north latitude.

Sunday, December 1The variable star Algol in Perseus appears faintest at 1:29 a.m. EST tomorrow morning, when it shines at magnitude 3.4. If you start watching it immediately after darkness falls, you can see it dim from its peak brightness (magnitude 2.1) to minimum and then rise back to maximum all in a single night. This eclipsing binary star runs through a cycle from minimum to maximum and back every 2.87 days, but the drop from peak brightness and subsequent rise lasts only about 10 hours. Algol appears in the northeastern sky after sunset and passes nearly overhead around 10 p.m. local time.

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The Sky This Week from November 22 to December 1 - Astronomy Magazine

Life from Space

Scientists want to understand how life arose on Earth. To do that, they must first unravel how organic molecules form and interact in environments without living things. Geologic activity has erased records of much of the chemistry that happened pre-life on Earth. But meteorites -- pieces of primitive solar system rocks that have fallen to Earth -- preserve chemical records of what the solar system was like in our planet's early days.

We rely on meteorites to tell this story, said Daniel Glavin, an astrobiologist at NASAs Goddard Space Flight Center and an author of the new study. Theyre basically frozen time capsules.

Scientists studying meteorites have already found molecules like amino acids and nucleobases, which are necessary for life. But they'd never seen ribose. This sugar makes up the backbone of RNA, a type of molecule responsible for carrying genetic messages in our cells. Furukawas team employed careful techniques to ensure they wouldnt destroy the sugars in their attempts to find them, and were able to uncover ribose and other sugars.

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Astronomers look inside meteorites and find the sugars needed for life - Astronomy Magazine

For the modern astronomer, satellites are just a part of life. There are more than 2,000 active ones currently orbiting Earth, and the smartest minds in space photography have managed to work out clever ways of removing the occasional fly over from their images of space.

But then there's Starlink. The first stages of SpaceX's plan to launch up to 42,000 satellites to provide Earth with complete internet coverage have clocked in at 122 objects so far; after the first major launch in May, astronomers were worried.

Now a second launch has occurred, and their concerns have truly started to materialise.

In the early hours of the morning on November 18 at the Cerro Tololo Inter-American Observatory (CTIO) in Northern Chile, the trail of newly launched Starlink satellites flew overhead, absolutely filling an image taken by the Dark Energy Camera (DECam).

Each one of those dotted line trails in the image below is a Starlink satellite.

(Cliff Johnson/Clara Martnez-Vzquez/DELVE Survey)

While taking about 40 exposures of the Small and Large Magellanic Clouds, SpaceX's Starlink satellite train entered the camera's vision around 90 minutes before sunrise, shining bright in the early morning sunlight and taking a whole five minutes to pass out of the telescope's view.

"Wow!! I am in shock," wrote CTIO astronomer Clara Martinez-Vazquez on Twitter.She noted there were 19 satellite trails, which is way more than a normal satellite pass.

Although most of the time the satellites will be dark in the night sky (which still presents some problems), just after the Sun goes down, or early morning when the sky is still black, sunlight can still hit the satellites, making them visible both by fancy astronomy telescopes, and just regular old binoculars.

"These things are big enough that when they're sunlit, they're bright enough to pick up with anything from binoculars and bigger," Cees Bassa from the Netherlands Institute for Radio Astronomy told Forbes.

And astronomers are not impressed. As we've reported before, they've brought up some big issues with Starlink.Firstly, there are going to be a lot of these objects in orbit, which could dramatically impact the way astronomers can see and listen to the sky.

"A full constellation of Starlink satellites will likely mean the end of Earth-based microwave-radio telescopes able to scan the heavens for faint radio objects," Swinburne University astronomer Alan Duffy told ScienceAlert in May after the first launch of Starlink satellites.

The second batch of 60 Starlink satellites was launched just over a week ago on November 11, so they haven't yet reached their final operational altitude - but that altitude is expected to be lower than for the first batch.

Sky watchers are also finding that Starlink are more reflective then other satellites. If thousands of extra satellites weren't already a problem on their own, the fact they are extra-shiny is just another thing astronomers are pulling their hair out about.

Astronomers can remove the trails from their images when Starlink swans into view, but much of the information scientists use is contained in the raw images, not the pretty photos we see. Additionally, it's one thing to remove a single satellite trail from an image, and another to remove 19.

So far, some people are coping by poking fun at SpaceX's Elon Musk on social media.

How astronomers and SpaceX will resolve these conflicting needs is still unknown, but with two more launches scheduled this year, there's a chance this won't be the last we'll hear about this problem.

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That Starlink Problem Astronomers Were Worried About Is Totally Happening - ScienceAlert

The arrangement of the two moons orbits is an example of what scientists call an orbital resonance. Repeating patterns in their orbits apply a regular set of gravitational forces to the two moons. In this case, the repeating forces keep the moons in their orbits, but resonances can be disruptive as well.

Astronomers have found many examples of orbital resonances in the solar system. Pluto and Neptune are in a resonance in which Pluto orbits the Sun twice for every three times that Neptune does. This resonance keeps the two objects orbits stable. Within the asteroid belt, there are gaps without asteroids where resonance patterns from Jupiters orbit disrupt the path of large groups of space rocks.

However, the newly discovered resonance of Naiad and Thalassa isnt like anything scientists have seen in the solar system so far. Naiad and Thalassa are two small moons, each about 60 miles or so in size, with orbits nestled close together. Thalassa circles Neptune in about 7.5 hours, while Naiad laps it from the inside, taking just 7 hours per orbit.

But Naiads orbit is tilted by almost 5 degrees relative to Thalassas orbit and Neptunes equator. This makes the little moon weave up and down in a wave motion that keeps it farther from Thalassa even as it passes by. Though it looks bizarre, the arrangement reinforces the moons orbits and keeps them stable despite being so near each other.

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A weird, orbital dance keeps these moons of Neptune safely on track - Astronomy Magazine