Category Archives: Astronomy

Bill Wren remembers exactly where he was when he was first called the Angel of Darkness.

He doesn't remember the year, but it was at a Texas Star Party, an annual gathering of 500 or so amateur astronomers held at the Prude Ranch in Fort Davis, Texas. Wren, a longtime advocate for the dark skies movement against light pollution as a staffer at UT's McDonald Observatory, was well known by that point, so a Texas Star Party attendee introduced him to a crowd with a new heavy metal-sounding nickname.

"It got a real nice laugh, and it got repeated," Wren says. "The media picked it up."

Wren is good-natured talking about the stark sobriquet even though if it's not his favorite. But if it gets people talking about the necessary steps to keep the night sky dark and the stars bright, he'll make the sacrifice.

"I'm willing to go along with just about anything, but I don't care for the moniker very much. I can do without it," Wren laughs. "Whatever works, you know?"

Earlier this week, Wren retired from the McDonald Observatory, where he made dark skies education and advocacy his work for 32 years.

"The skies over McDonald Observatory are among the darkest of any professional observatory in the United States, in no small measure thanks to Bill Wren," Taft Armandroff, director of McDonald Observatory, said in a statement upon Wren's retirement.

Wren says it was time for him to pack it in, to give someone else a chance to take the baton and run with it. "Life is short. I was past due. The pandemic made things a little less fun, working from home all the time," he says.

That home was university housing at the observatory. The University of Texas at Austin, which operates the McDonald Observatory, chose West Texas' Davis Mountains for its site in 1933 because its skies are some of the darkest in the United States. Since then, light pollution has worsened, especially with drilling rigs cropping up in West Texas during oil booms. Every time that happens, bright lights shine into the night skies, which is detrimental to both the enjoyment of the cosmic view and the scientific work conducted by astronomers at the McDonald Observatory.

USA, Texas, Fort Davis, McDonald Observatory. Houses 430 inch Hobby-Eberly Telescope. Elevation 6791 feet.

A self-taught astronomer, Wren grew up in the hills of Missouri, where, he says, "the starry sky was splendid, almost like wallpaper." He moved to Houston at 15, and noticed that the sky looked different in the city after dusk. On a hunch, he drove out on 290 toward Hempstead. He was awestruck by the stars in the dark night sky.

"Wow, you know, you couldn't see that when I looked at yesterday," Wren remembers thinking. "And it's certainly gotten a lot worse."

That realization led to a lifelong interest in amateur astronomy, beginning with spotting Saturn's rings and Jupiter's moons from his backyard. He eventually bought a larger telescope and started traveling more with his Peterson Field Guide,learning the night sky over the course of a few years. While working at a runaway shelter in Austin and helping a state agency start its suicide hotline, he tutored astronomy students at UT Austin using his self-taught knowledge. He met Frank Bash, UT astronomy professor and the director of the McDonald Observatory, who was impressed with Wren and let him know that the visitor's center had a job opening.

"Thirty days later I pulled the plug on my counseling career in Austin and moved to West Texas," Wren says. "March 1, 1990 was just in time for spring break. It was baptism by fire."

During Wren's second month in Fort Davis, he was encouraged to attend a meeting of the International Dark Sky Association at the University of Arizona campus. He learned that areas could be well-lit without polluting the sky, that people were wasting light and ruining beautiful sights and complicating research for astronomers.

"I wouldn't call it a born-again experience because it's almost like being evangelized," Wren says. "It was just like wow, this is I need to help spread the word on this."

So that's what he did.

The summer Milky Way rises over the McDonald Observatory near Fort Davis, Texas.

In addition to hosting Star Parties and giving tours, Wren gave talks on dark skies for years. It was around 2011, during the oil and gas boom in the Permian Basin, he realized he needed to work directly with companies to keep the skies dark. It wasn't just the drilling sites, but from the adjacent commerce hotels, new housing, chain stores that comes with oil exploration. He remembers giving a presentation to San Antonio-based Pioneer Energy Services, whose president owned a ranch outside Marathon.

"He was waxing poetically about seeing the Milky Way horizon-to-horizon," Wren says. "He said, 'Yes, this is worth protecting, here's our fleet of drilling rigs. See what you can do with the lighting."

Around that time Wren stopped most of his other work at the observatory to focus on dark skies full time. He worked with many oil and gas companies to alter their lighting systems to reduce light pollution, he says, without much pushback at all. In fact, in most cases the sites became safer and with higher visibility and reduced glare, a true win-win for each side.

"And they do recognize the value in the night sky," Wren says. "Many of them do ... well, probably many of them don't. But there are people that get it."

Though light pollution can be reversed, dark skies are disappearing around the country as fewer locations with high visibility remain truly remote. Even though Wren is retiring, he is still staying active in the dark skies community from his new home in Cloudcroft, New Mexico.

"The places where people can go to see an actually dark night sky are rapidly shrinking and becoming fewer and farther between," Wren says. "And it's becoming the case that McDonald Observatory in particular, but the Big Bend region in general, is being recognized as a dark sky destination, a place where people can take in the night sky something with which most of us have lost track of the wonder, the splendor of it all. We're trying to get people to buy into preserving the night skies in far West Texas."

Wren says the best way for people to get the picture is to get a visual demonstration. He says that once you see the effects of light pollution on dark skies, you can't unsee it.

"Being able to do a demonstration or being able to point it out to someone so they can see it with their own eyes can be a very powerful, life altering thing," Wren says. "For some pool souls, it'll be cursing my name til the day they die."

Such is the blessing and the curse of the Angel of Darkness.

The rest is here:

They called him the Angel of Darkness. But this astronomer just wanted to keep West Texas skies pure. - mySA

The number of planets discovered beyond our Solar System has grown exponentially in the past twenty years, with 4,919 confirmed exoplanets (and another 8,493 awaiting confirmation)! Combined with improved instruments and data analysis, the field of study is entering into an exciting new phase. In short, the focus is shifting from discovery to characterization, where astronomers can place greater constraints on potential habitability.

In particular, the characterization of exoplanet atmospheres will allow astronomers to determine their chemical makeup and whether they have the right characteristics to support life. In a new study led by the University of Lund, an international team of researchers characterized the atmosphere of one of the most extreme exoplanets yet discovered. This included discerning what could be several distinct layers that have particular characteristics.

The study, which recently appeared in the journal Nature Astronomy, was conducted by researchers from the Lund Observatory (University of Lund), the National Centre of Competence in Research (NCCR) PlanetS, the Max Planck Institute for Extraterrestrial Physics, the National Institute for Astrophysics (INAF), the European Southern Observatory (ESO), and multiple universities and research institutes from the UK, Canada, and Chile.

As Earths atmosphere demonstrates, planetary atmospheres do not consist of a single uniform envelope but many layers, each with characteristic properties. The lowest layer of our atmosphere, which extends from sea level to the highest mountain peaks (the troposphere), is where most meteorological phenomena occur since it contains the most water vapor of any layer. Above that is the stratosphere, which contains the ozone layer that shields the surface from potentially harmful ultraviolet radiation.

Next is the mesosphere, which is very thin and cold but still dense enough that meteors will burn up as they pass through it. The thermosphere is next, where temperatures increase again with altitude (due to Solar heating).The uppermost layer is the exosphere, which is too thin for any meteorological phenomena to occur. However, the Aurora Borealis and Aurora Australis sometimes occur in the lower part of the exosphere, overlapping into the thermosphere.

For the sake of their study, the international team examined the exoplanet known as WASP-189b, a Hot Jupiter located 322 light-years from Earth. This planet was discovered in 2018 using the Wide-Angle Search for Planets (WASP) consortium, while extensive follow-up observations were conducted in 2020 using the ESAs CHaracterising ExOPlanets Satellite (CHEOPS). These revealed a planet about twice the radius of Jupiter that orbits its host star 20 times closer than Earth orbits the Sun leading to daytime temperatures of 3,200 C (5,790 F).

Using more recent observations with the High Accuracy Radial velocity Planet Searcher (HARPS), a spectrograph integrated with the 3.6-meter telescope at the ESOs La Silla Observatory, the team was able to examine the atmosphere of this Hot Jupiter for the first time. These spectral observations revealed an atmosphere with the chemical fingerprints of iron, chromium, vanadium, magnesium, and manganese.

As Lund doctoral student Bibiana Prinoth (who was the lead author on the study) explained in a University of Bern press release:

We measured the light coming from the planets host star and passing through the planets atmosphere. The gases in its atmosphere absorb some of the starlight, similar to Ozone absorbing some of the sunlight in Earths atmosphere, and thereby leave their characteristic fingerprint. With the help of HARPS, we were able to identify the corresponding substances.

In addition to the previously-mentioned minerals, the team was interested to find traces of titanium oxide gas. This substance has a melting point of 1,843 C (3350 F) and is very scarce on Earth, where it is typically used as a pigment known as titanium white. Because of its particular properties, this gas may play an important role in the atmosphere of WASP-180b similar to how ozone played an important role in the evolution of Earths atmosphere.

Like ozone, Titanium oxide absorbs short-wave electromagnetic radiation, including ultraviolet light. Therefore, the detection of this compound could indicate that there is a layer in WASP-189 bs atmosphere that interacts with stellar radiation the same way the Earths Ozone Layer does. Already, researchers have found hints of this and other layers on the ultra-hot Jupiter-like planet. As Prinoth explains:

In our analysis, we saw that the fingerprints of the different gases were slightly altered compared to our expectation. We believe that strong winds and other processes could generate these alterations. And because the fingerprints of different gases were altered in different ways, we think that this indicates that they exist in different layers similarly to how the fingerprints of water vapour and ozone on Earth would appear differently altered from a distance, because they mostly occur in different atmospheric layers.

These results may change how astronomers investigate exoplanets. In the past, astronomers tended to assume that the atmosphere of exoplanets existed as uniform layers and tried to characterize them as such. But these latest results demonstrate that even the atmospheres of extreme planets like ultra-Hot Jupiters have complex three-dimensional structures. AS co-author Kevin Heng, a professor of astrophysics at the University of Bern and a member of the NCCR PlanetS, concludes:

We are convinced that to be able to fully understand these and other types of planets including ones more similar to Earth, we need to appreciate the three-dimensional nature of their atmospheres. This requires innovations in data analysis techniques, computer modelling and fundamental atmospheric theory.

Further Reading: Bern University, Nature Astronomy

Like Loading...

Go here to see the original:

Astronomers Measure the Layers of an Exoplanet's Atmosphere - Universe Today

A team of astronomy researchers has discovered a surprising fact from the first couple of billion years of the universe: there were at least some large groups of galaxies that were already burning out at the time, contrary to the general pattern of galaxies having vigorous star formation then.

The massive grouping of at least 38 young galaxies that was discovered, called protocluster MAGAZ3NE J0959, is about 11.8 billion light-years away from Earth, and was found using the W. M. Keck Observatory in Hawaii. At the center of MAGAZ3NE J0959 is an ultra-massive galaxy with more than 200 billion suns.

The discovery of this protocluster with a population dominated by ultra-massive galaxies with halted star-formation activity was surprising, said Danilo Marchesini, a Tufts professor of astronomy who was part of the research team. It shows that even in the early universe there was already a great range of diversity in terms of the properties of galaxies.

We were not expecting this, and this finding raises new exciting questions, said Marchesini, who was joined on the project by Tufts postdoctoral researcher Marianna Annunziatella.

One issue is if the censuses of distant protoclusters are biased or incomplete, he said. The fact that previously reported protoclusters at this epoch were found to contain mostly star-forming galaxies may be evidence that our view of dense environments in the early universe is at least incomplete, or most likely biased, as finding distant quiescent galaxies is much harder than finding actively star-forming galaxies.

The research team, led by University of California at Riverside astronomers Ian McConachie and Gillian Wilson, reported their findings in the Astrophysical Journal. In marked contrast to protoclusters previously reported at this epoch which have been found to predominantly contain star-forming members, MAGAZ3NE J0959 was found to have an elevated fraction of quiescent galaxies, the research team wrote. This suggests that protoclusters exist in a diversity of evolutionary states in the early Universe.

Looking ahead, the researchers note in the paper that future ground and space telescopes with the capability to survey significantly wider areas, such as the James Webb Space Telescope . . . will undoubtedly facilitate the discovery of larger samples, allowing better insight into the uniqueness of MAGAZ3NE J0959, and helping to propel our understanding of the formation of UMGs [ultra-massive galaxies] and protoclusters into the even earlier Universe.

Taylor McNeil can be reached at taylor.mcneil@tufts.edu.

Read the rest here:

Astronomers Find Burned Out Galaxies in Ancient Universe - Tufts Now

Stochastic Processes and Dual Pairs of Operators

Abstract. A new harmonic analysis for Krein-Feller operators is presented. We first show that a Krein-Feller operator is associated to pairs of measures assumed positive, sigma-finite, and non-atomic. Our approach to the problem is via dual pairs of operators, referring to the corresponding pairs of L^2 Hilbert spaces.The operator pairs used for our Krein-Feller analysis consist of two specific densely defined (unbounded) operators, each one contained in the adjoint of the other. We show how this approach yields a rigorous analysis of the corresponding Krein-Feller operators as closable quadratic forms. For given measures, including the case of fractal measures, we compute the associated diffusion, Markov processes, semigroups, Dirichlet forms, and generalized heat equations. Key tools for our analysis are the use of associated reproducing kernel Hilbert spaces (RKHSs), time-change, and Gaussian fields.

ZOOM ID:965 4759 0309

Read more here:

Operator Theory Seminar - Professor Palle Jorgensen; Univ of Iowa | Physics and Astronomy | The University of Iowa - Iowa Now

Completeness and complex probabilities in descrete systems

Abstract: I discuss a general real-time path integral treatment of discrete systems motivated by Jorgensen and Nathanson's treatment of real time path integrals based on complex probabilities. For imaginary times in the continuum theory there is a path measure that can be alternatively considered as a probability measure; while for real time there is no countably additive measure on the cylinder sets of paths, the probability interpretation survives if the notion of probability is properly extended to complex probabilities. In the discrete case the complex probability arises from the completeness relation, there are no Fresnel integrals, and the space of paths are cylinder sets of paths that take on discrete values of complementary pairs of observables at different time slices. The cylinder sets of discrete paths are in 1-1 correspondence with ordered sequences of transition amplitudes involving complementary pairs of operators. I will discuss a trivial application to quantum field theory.

ZOOM ID:956 5927 4425

Follow this link:

Math Physics Seminar - Professor Wayne Polyzou | Physics and Astronomy | The University of Iowa - Iowa Now

Maunakea. PC: University of Hawaii Hilo

The decommissioning of the California Institute of Technology Submillimeter Observatory on University of Hawaii-managed lands on Maunakea will be completed by the end of 2022, according to aFebruary 10 news releasefrom CSO.

The Hawaii State Board of Land and Natural Resources unanimously approved a conservation district use permit on Jan. 14, 2022 for the removal and site restoration of the CSO observatory.

CSO is one of two Maunakea telescopes currently in the final stages of the decommissioning process, established in the Maunakea Comprehensive Management Plan. The UH Hilo Hk Kea Telescope is on track to be decommissioned in 2023.

The decommissioning of these first two observatories will be milestones in the stewardship of the mauna, said Greg Chun, executive director of the UH HiloCenter for Maunakea Stewardship. This is a very thorough process as a lot of work went into the development of the CMP more than a decade ago, which guides our management of Maunakea.

CMS is responsible for administering the BLNR approved CMP along with the new Maunakea Master Plan, approved by the UH Board of Regents in January 2022, and the administrative rules.

The new Master Plan set a limit of nine operating astronomy facilities on Maunakea by 2033. Five of the 14 astronomy sites will be closed permanently to astronomy development once the existing facilities there have been decommissioned.

More broadly, the Master Plan serves as a framework for aligning land-use decisions consistent with UHs mission and purpose. The administrative rules cover public and commercial activities.

The CMP addresses activities like cultural, natural, and scientific resource protection, education and outreach, permitting and compliance, infrastructure and maintenance, construction activities, operations, and monitoring. The CMP has four sub-planspublic access, cultural resources management, natural resources management and observatory decommissioning that further specify those activities. According to the decommissioning sub-plan, the Maunakea Observatories are responsible for the cost of decommissioning.

The CDUP for CSO sets the terms and conditions required for decommissioning. As part of the process, CSO has completed an archeological assessment, a cultural setting analysis, a hydrogeological evaluation, a biological inventory, a biological setting analysis, a traffic analysis and an asbestos/lead paint/mold survey.

See original here:

Maunakea telescope to be decommissioned this summer - Maui Now

ONEILL A course for anyone with an interest in the night (or daytime) sky will be offered by Northeast Community College in ONeill later this month.

The class, Astronomy: Beginning Observational Astronomy/Atmospheric Optics (HORC 5110/22S and CRN No. 70214) meets Monday, Feb. 28, from 6:30 to 8:30 p.m., in Room 132 in the Northeast Community College Extended Campus in ONeill, 505 East Highway 20.

With instructor Mark Urwiller, participants will explore concepts of celestial mechanics, types of objects to view day or night and equipment that can be used to view the sky. The class will help participants enjoy the sky without special equipment, use the equipment they already have or select equipment to buy if they want to take their interest to the next level.

Participants are asked to bring a laptop, tablet or smartphone, if available. They are not required.

Pre-registration is required. To register, call Northeast Community College in O'Neill at 402-336-3590.

Read more:

Beginning astronomy course to be offered at Northeast in O'Neill - Norfolk Daily News

An artists rendition of a red supergiant star transitioning into a Type II supernova, emitting a violent eruption of radiation and gas on its dying breath before collapsing and exploding. Credit: W. M. Keck Observatory/Adam Makarenko

Its another first for astronomy.

For the first time, a team of astronomers have imaged in real-time as a red supergiant star reached the end of its life. They watched as the star convulsed in its death throes before finally exploding as a supernova.

And their observations contradict previous thinking into how red supergiants behave before they blow up.

An artists impression of a red supergiant star in the final year of its life emitting a tumultuous cloud of gas. This suggests at least some of these stars undergo significant internal changes before going supernova. Credit: W.M. Keck Observatory/Adam Makarenko

A team of astronomers watched the drama unfold through the eyes of two observatories in Hawaii: Pan-STARRS on Haleakala, Maui, and the W. M. Keck Observatory on Maunakea, Hawaii Island. Their observations were part of the Young Supernova Experiment (YSE) transient survey. They watched the supernova explosion, named SN 2020tlf, during the final 130 days leading up to its detonation.

For the first time, we watched a red supergiant star explode! Wynn Jacobson-Galn, UC Berkeley

The title of the paper presenting the discovery is Final Moments. I. Precursor Emission, Envelope Inflation, and Enhanced Mass Loss Preceding the Luminous Type II Supernova 2020tlf. The paper is published in The Astrophysical Journal and the lead author is Wynn Jacobson-Galn, an NSF Graduate Research Fellow at UC Berkeley.

This is a breakthrough in our understanding of what massive stars do moments before they die, said Jacobson-Galn, in a press release. Direct detection of pre-supernova activity in a red supergiant star has never been observed before in an ordinary Type II supernova. For the first time, we watched a red supergiant star explode!

Its like watching a ticking time-bomb. Raffaella Margutti, UC Berkeley

The discovery dates back to the Summer of 2020. At that time, the progenitor star experienced a dramatic rise in luminosity. Pan-STARRS detected that brightening, and when Fall came around the star exploded as SN 2020tlf. The supernova is a Type II supernova, where a massive star experiences a rapid collapse and then explodes.

This video is an artists rendition of the red supergiant star transitioning into a Type II supernova, emitting a violent eruption of radiation and gas on its dying breath before collapsing and exploding. Credit: W. M. Keck Observatory/Adam Makarenko

The team used the Keck Observatorys Low-Resolution Imaging Spectrometer (LRIS) to capture the supernovas first spectrum. The LRIS data showed circumstellar material around the star when it exploded. That material is likely what Pan-STARRS saw the star ejecting in the summer before it exploded.

Keck was instrumental in providing direct evidence of a massive star transitioning into a supernova explosion, said senior author Raffaella Margutti, an associate professor of astronomy at UC Berkeley. Its like watching a ticking time bomb. Weve never confirmed such violent activity in a dying red supergiant star where we see it produce such a luminous emission, then collapse and combust, until now.

This figure from the study shows the supernova pre- and post-explosion. The top panel shows the total of all electromagnetic radiation emitted by the event across all wavelengths, in green. The middle panel shows black-body temperatures in red, and the bottom panel shows the radii in blue. Image Credit: Jacobson-Galn et al, 2022

After the explosion, the team turned to other Keck instruments to continue their observations. Data from the DEep Imaging and Multi-Object Spectrograph (DEIMOS) and Near Infrared Echellette Spectrograph (NIRES) showed that the progenitor star was 10 times more massive than the Sun. The star is in the NGC 5731 galaxy about 120 million light-years away.

The teams observations led to some new insight into Type II supernovae and their progenitor stars. Prior to these observations, nobody had seen a red supergiant display such a spike in luminosity and undergo such powerful eruptions before exploding. They were much more placid in their final days as if they accepted their fates.

Red supergiant stars eject material prior to core collapse. But that material ejection takes place on much longer timescales than SN 2020tlf. This supernova emitted circumstellar material (CSM) for 130 days prior to collapse, and that makes it a bit of a puzzle. The bright flash prior to the stars explosion is somehow related to the ejected CSM, but the team of researchers isnt certain how they all interacted.

Artists impression of a Type II supernova explosion which involves the destruction of a massive supergiant star. Credit: ESO

The significant variability in the star leading up to collapse is puzzling. The powerful burst of light coming from the star prior to exploding suggests that something unknown happens in its internal structure. Whatever those changes are, they result in a mammoth ejection of gas before the star collapsed and exploded.

In their paper, the authors discuss what may have caused the ejection of gas. One possibility is wave-driven mass loss, which occurs in the late stages of stellar evolution. It occurs when the excitation of gravitational waves by oxygen or neon burning in the final years before SN can allow for the injection of energy into the outer stellar layers, resulting in an inflated envelope and/or eruptive mass-loss episodes, they write. But current wave-driven models dont match the progenitor stars ejection of gas. Theyre consistent with the progenitor stars radius in its last 130 days, but not consistent with the burst of luminosity.

In the conclusion of their paper, the authors sum things up succinctly. Given the progenitor mass range derived from nebular spectra, it is likely that the enhanced mass loss and precursor emission are the results of instabilities deeply rooted in the stellar interior, most likely associated with the final nuclear burning stages. Energy deposition from either gravitational waves generated in neon/oxygen burning stages or a silicon flash in the progenitors final ?130 days could have ejected stellar material that was then detected in both pre-explosion flux and the early-time SN spectrum.

If theres one supernova that behaves like this, there must be more. The teams findings mean that surveys like the Young Supernova Experiment transient survey now have a way to find more of them in the future. If the survey finds more stars ejecting material like this one, then they know to keep an eye on it to see if it collapses and explodes.

I am most excited by all of the new unknowns that have been unlocked by this discovery, said Jacobson-Galn. Detecting more events like SN 2020tlf will dramatically impact how we define the final months of stellar evolution, uniting observers and theorists in the quest to solve the mystery of how massive stars spend the final moments of their lives.

Originally published on Universe Today.

For more on this research:

Read the original:

Astronomers Watch a Star Die and Then Explode as a Supernova For the Very First Time - SciTechDaily

Home Lifestyle This $74K Astronomy Watch Aims to Liberate the Mind; Shows Earth, Sun, Moons Positions

Horologist Ulysse Nardin claims its Moonstruck design features reinvented mechanics that will reproduce the suns trajectory and lunar cycles in a simple-to-decrypt face. Hmm.

In a few words, the Blast Moonstruck is an elaborate analog watch. Through its combination of highly specialized intricacies, the astronomical watch provides wearers with info about the solar position, lunar phase, and, conveniently the time at a glance.

High-end wristwatches are nothing new. And the most sought-after iterations tend to be analog. Horology is a mechanistic art form that is incredibly complex, and, as a result, I find myself wedged halfway down any rabbit hole that Ive attempted on the subject.

So when I read the press release telling me that this bourgie idea of a ticker set in motion the primordial elements of the visible celestial mechanisms so that everyone can gain a poetic understanding, I was three things: very lost, very skeptical, and very, very curious.

Heres what I figured out. And, presumably, what you need to know.

Its makers boast the timepiece as a scientific representation of considerable oneiric potential (dreamlike I had to look that one up, too). According to the brand, the watchs solar and lunar indicators provide great leaders (but also sailors) with the information needed to predict the spring tides.

A top-down view with the North Pole at the center of the dial and a domed sapphire crystal make observers feel as if they are at the center of the cosmos, the Ulysse Nardin team says.

A three-dimensional sun begins its cycle at 12 oclock and an aventurine disk stands in as the night sky. That disk, by some magnificent gear train, plays out the moons phases and completes a full rotation every 24 hours.

Similarly, the sun completes its rotation along the Moonstrucks 18-carat rose gold outer bezel every 29.5 days.

Speaking of material makeup, the case comprises black ceramic and DLC titanium. Customers can choose from black alligator, black velvet, or black rubber straps. But as the saying goes, in for a penny, in for the full alligator leather.

A simple winding crown adjusts the time, and two rectangular buttons operate the dual-time setting function. See the full list of the tickers functions and specs below.

To learn more and place an order for the $73,900 Blast Moonstruck, head to ulysse-nardin.com.

Citizens Promaster series is legendary. Their solar-powered diver has been featured not once, but twice here on GearJunkie. So, when the makers of this fan-favorite announced that their latest model had sprouted legs and climbed out of the sea, we were immediately intrigued. Read more

Read more:

This $74K Astronomy Watch Aims to 'Liberate the Mind'; Shows Earth, Sun, Moon's Positions - GearJunkie

We already knew the asteroid 130 Elektra was special. Astronomers previously discovered it had two moons, making it a rare triple asteroid system. Now a third moon may have been found, making it even more uncommon the first-known quadruple asteroid in the solar system.

Elektra was first discovered in 1873, orbiting in the asteroid belt between Mars and Jupiter. Oblong-shaped and 160 miles across on its longest side, it is a relatively large asteroid and completes an orbit of the sun every five years.

In 2003, the first moon was discovered orbiting Elektra, and in 2014 a second. The discoveries were interesting, but not unusual more than 150 asteroids are known to have one or two moons, in the same way planets can have moons that are gravitationally bound to them. Multiple moons can be found around large asteroids, said Bin Yang, an astronomer from the European Southern Observatory in Chile who discovered Elektras second moon. A NASA mission, DART, is on target to collide with one such asteroids moon later in the year.

But until now, an asteroid with three moons has eluded astronomers. Anthony Berdeu from the National Astronomical Research Institute of Thailand and colleagues used images from the Very Large Telescope (V.L.T.) in Chile to take a closer look at Elektra, and they found evidence for a previously hidden moon inside the orbits of the other two.

This is the first asteroid with three moons, Dr. Berdeu said. We are pretty confident. Its quite exciting.

Their results were published Tuesday in the journal Astronomy & Astrophysics.

At a paltry one mile across, the moon would be slightly smaller than its siblings at 1.2 and 3.7 miles across. It swings around Elektra once every 16 hours at a distance of only 220 miles. To an observer standing on the third moons surface, Elektra would loom large in the sky.

Dr. Berdeu says he was able to find the moon using a new algorithm to eke out its extremely faint light in images taken by the V.L.T. The data reduction techniques employed by the algorithm allowed for a sharper image of Elektra and its surroundings.

Dr. Yang, who was not involved in this paper, said that she and other astronomers had been trying to look for quadruple systems for a while, and that her team also saw tantalizing hints of this third moon in their studies of 130 Elektra. This discovery would be a very exciting result, she said, although further observations will be needed to confirm the moons existence.

Alan Fitzsimmons, an astronomer from Queens University Belfast who was also not involved in the paper, says the moons are most likely chunks of Elektra that were broken off in a collision when another object smashed into the asteroid in the past. They all look like theyre from the same material, he said.

Further study of this system could reveal the stability of such multi-moon asteroids. This third moons orbit is misaligned to the other two, something thats very strange, Dr. Berdeu said. Dr. Yang said that she thought the system was unstable and that the inner moons may eventually fall back onto Elektra.

It could also tell us more about the formation of multi-moon asteroids. This new finding will inspire modelers to look at asteroid impact formation, and try to set a limit on how many moons an impact can form, Dr. Yang said. How many moons can a system really sustain?

Further studies are expected to unearth more quadruple systems too. New telescopes, such as the Extremely Large Telescope currently being built in Chile, will have the observing power necessary to more easily spot these multi-moon asteroid systems.

And astronomers may not stop at quadruple asteroids. There is no limit to what we can find, Dr. Berdeu said. We expect to find more quadruple systems, and why not quintuple or sextuple.

Read the rest here:

The First Quadruple Asteroid: Astronomers Spot a Space Rock With 3 Moons - The New York Times