Category Archives: Astronomy

[This post originally appeared as part of Recommendation Machine, IndieWires daily TV picks feature.]

Where to Watch Astronomy Club: Netflix

Watching Astronomy Club is a little like getting a sketch comedy syllabus. In the best possible way, a group of eight comedians manages to tick the boxes of everything you might expect from the show. Over six Netflix episodes, they fill out a collection of original songs, impressions, fake trailers, celebrity cameos, and even an absurdist spin on a holiday treat.

What ends up making these episodes really work, though, is the reality show framework that these are all built around. Yes, everyone is playing themselves. But even getting to know the scripted versions of Shawtane Bowen, Jonathan Braylock, Ray Cordova, Caroline Martin, Jerah Milligan, Monique Moses, Keisha Zollar, and James III help make the sketches around them a little bit sharper. Its a shortcut to knowing when everyone is playing against type or drafting off their own insecurities or using everyone elses assumptions to their own advantage. If the stuff surrounding it wasnt so thoroughly entertaining, it would be enough to have that crowded house be its own show.

But another Astronomy Club strength is that its balanced. Theres a feeling that all of this writing is coming from a group with a time-tested comfort, all without having to be restricted to one particular lane. The fake game show What You Shoulda (hosted with perfect smiling exasperation by Martin) has a different feel than something like a sketch built around Braylocks eerily scrunched Resting Creep Face. That all coexists alongside the running joke through the second episode that gives the whole group a chance to jump in on the Ice Cube gag of their choosing. (Milligan and James IIIs dueling Cedric the Entertainers are definitely an added bonus.)

Theres also a strength in how the group can go an extra step. Whether its their take on LARPing, bra sizes, famous substitute English teachers, or roles for Black actors, they zero in on one of the most satisfying things that sketch comedy can do: surprise you with a setup and let you live inside it before pointing you in a completely different direction, all in just a handful of minutes. (M Shelly Conners piece for the AV Club outlines the way that Astronomy Club, like other Black-led sketch comedy shows before it, uses that last inversion as a way of challenging both stereotypes and expectations.)

Even the smallest-scale sketches can zoom out at any time, using a talented team of eight people to help make an idea go bigger. The Shade Off that made it to the Netflix show draws from a pair of spiritual predecessors that the group made as part of a digital series for Comedy Central. Each of them benefits from being able to have multiple people who can throw curveballs into whats happening, sometimes with only a word or two or even a simple glance. With the group writing and performing their own material, Astronomy Club plays to members individual strengths and avoids having to tackle a simple premise in only one way.

That they never had the chance to build on this solid foundation remains one of the more baffling recent Netflix programming choices. (Last summer, Zollar, Braylock, and Moses spoke about the platforms decision not to renew the show.) Even for a show that arrived fully ready to flip the sketch show playbook, its hard not to feel like they were all ready for so much more.

Pair It With: James III, Braylock, and Milligan host the podcast Black Men Cant Jump in Hollywood, which looks at individual films with an eye toward how they shifted on-screen representation and opportunities for Black creators. Along with the occasional guest, these three bring the same easy chemistry they have in front of the camera while also talking honestly about their own industry experiences. Awards time is always a good time to tune into BMCJIH, so as fall films start to make their way to audiences, last years episodes on Soul and One Night in Miami are good examples of how these discussions can be funny and frank at the same time.

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Astronomy Club Is Still an Essential Part of the Netflix Sketch Comedy Lineup - IndieWire

Feature Hundreds of scientists around the world have been quietly volunteering their time to prevent low Earth orbit satellites from destroying astronomy.

Space is getting more and more crowded. As technology has advanced, lobbing things into space has become cheaper and more accessible for commercial entities. Private companies are elbowing in and flinging their own satellites into low Earth orbit, typically promising to deliver faster and faster wireless broadband internet from their constellations.

When SpaceX began sending its Starlink birds up in 2018, the astronomy community realized the flying blocks of metal brightened up the night sky and threatened to drown out the glow of distant stars and galaxies. Constellations of Starlink satellites whizzing in front of telescopes left dazzling streaks in their wake, making it difficult for astronomers to observe the cosmos.

The problem is only getting worse. SpaceX now has 1,600-plus internet-relaying satellites in the sky, while similar programs from the likes of Amazon, OneWeb, and Boeing are emerging.

SpaceX has plans to launch 42,000 satellites; Amazon has asked for permission to lob 7,774.

Bright satellite streaks ruining a view of Perseid meteor shower in 2018 (click to enlarge). Image source: Eckhard Slawik

"We are absolutely losing some science," Jonathan McDowell, an astronomer at the Harvard-Smithsonian Center for Astrophysics, tells The Register. "How much science we lose depends on how many satellites there end up being. You occasionally lose data. At the moment it's one in every ten images."

Telescopes can try waiting for a fleet of satellites to pass before they snap their images, though if astronomers are trying to track moving objects, such as near-Earth asteroids or comets, for example, it can be impossible to avoid the blight.

"As we raise the number of satellites, there starts to be multiple streaks in images you take. That's no longer irritating, you really are losing science. Ten years from now, there may be so many that we can't deal with it," he added.

McDowell co-chaired the Algorithms Group for SATCON2, a workshop hosted by the American Astronomical Society, and warned that scientists need to figure out how to mitigate the issue now when satellite numbers are still low before it's too late to catch up. One possible solution they're starting to explore is machine learning. It's possible AI software can be trained to automatically mask some of the bright satellite streaks in astronomical images.

One of the recommendations in the workshop's giant report [PDF] involves assembling a team of astronomers and computer scientists to develop a range of open-source tools for future researchers to use. In order to build the algorithms, they need to gather a range of datasets made up of images snapped from various telescopes. The shots need to show the same patch of sky with and without satellite trails. Computer-vision algorithms can then be taught to detect the annoying streaks and adjust the pixels to cover them up.

Leaders of the workshop are trying to form collaborations between observatories and secure research funding to seriously develop a central hub for these future tools. At the moment, astronomers interested on working on the problem do it in their spare time or are scatted across various academic projects.

Hossen Teimoorinia, a researcher at the University of Victoria, Canada, has been experimenting with different techniques for a while. "If you want to remove satellite traces to find moving objects you need to prepare a very good dataset," he tells El Reg.

Not only do you have to collect images from observatories and institutions, they need to show exactly the same region of space with and without satellite interference and have to be pre-processed to make sure they're the same size and resolution, and so on. The other possibility is to add fake, artificial trails in clean images of the night sky to increase the amount of training examples.

"It's a little bit time consuming. But hopefully we will be able to train one main model and use transfer learning so it can be fine-tuned to handle different images taken from different telescopes," Teimoorinia says.

It'll be tricky, however, to develop a single model that is robust enough to handle the various properties of different telescopes. They have different resolutions, noise characteristics, exposure times, and operate across different wavelengths. "We may have to build algorithms that work for specific telescopes, it's complicated," McDowell says.

Ideally, these tools will, one day, be packaged as an easy-to-use Python library and astronomers will be able to apply them to their own images.

AI cannot do magic, however, Teimoorinia warns. Some science will still be lost in the process. Even if machine learning can erase the ugly satellite streaks so astronomers can monitor asteroids and comets, any stars or galaxies obstructed by the glinting trails will be removed, too. While you can track asteroids and comets frame by frame as they move across the sky, stars and galaxies tend to remain hidden behind a satellite's trail and will be obliterated during the cleanup.

Don't forget that these constellations of metallic birds reflect sunlight, and their radio signals can interfere with readings, making it potentially difficult for astronomers to accurately record light levels to estimate the distances or temperatures of faraway stars or to discover new galaxies.

Sometimes the opposite can happen, where something glittering in the sky doesn't just make it tough for astronomers to observe objects, it can make them see things that don't even exist.

A flash from the farthest galaxy discovered in the observable universe, GN-z11, generated excitement in the research community. People believed they had spotted the most distant gamma-ray flash ever from an exploding massive dead star or a black hole. But now some reckon it was just the reflection from a fragment of a broken-up spent Russian rocket that happened to be in view at the wrong time as astronomers observed GN-z11.

Similar mistakes could be made in the future with broadband satellites, McDowell says. "A lot of the time the effect of a satellite is really obvious, other times it's more subtle. If the light from a satellite is sent down a fiber for spectroscopy, it can contaminate the spectrum with reflected sunlight from the satellite. It could screw up data without you trying to spot it. Ordinary galaxies suddenly look really interesting, the bright lights make it look like something weird is going on there."

It's clear machine-learning-driven image processing simply won't be a panacea. The blight may well need a more drastic measure: limiting the number of low Earth satellites in space altogether. How many is too many? What is the maximum number of satellites that can be in space at any given time to make sure space is still observable?

"That's a wild guess at the moment," Richard Green, an astronomer at the Steward Observatory in the US, tells The Register.

Green believes the United Nations Outer Space Treaty, signed in 1967 to ensure "outer space shall be free for exploration and use by all States" and that "States shall avoid harmful contamination of space and celestial bodies," could be used to regulate global satellite launches in low Earth orbit.

America isn't the only country sending devices into space to provide broadband services. Even if it does try to control the number of satellites going up, it can't solve the problem on its own. "The UK and Canada are doing it too. China as well, although we know less about what's going on there," Green says.

It requires the cooperation of countries all around the world and there has yet to be an all-inclusive international discussion on the matter even though the International Astronomical Union is trying to appeal to the UN's Committee on the Peaceful Uses of Outer Space. "We need to seriously implement new policies or it'll become a free-for-all, where space will be taken by first come, first served," he adds.

Space is for everyone and the discoveries that have been made affect us all, McDowell concludes. "The fundamental things we've learned about ourselves, like the fact that we're all made out of star dust, for example, are immediately relevant. And who knows what we're going to discover or not discover in the next century because of satellites?"

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AI algorithms can help erase bright streaks of internet satellites but they cannot save astronomy - The Register

You are invited to our next Physics and Astronomy Colloquia event taking place on Tuesday, November 16, 2021, from 12:10 - 1 PM in CNS 206/208. At this seminar, we will be joined by Megan Smith from Hamilton College.

Presenter: Megan Smith from Hamilton College

Title: The Effect of the Magnetic Rayleigh-Taylor Instability in Thin Black Hole Accretion Disks

Abstract: One of the big questions in our understanding of black hole-accretion disks systems is how matter from the disk falls onto the black hole, since angular momentum conservation should keep that matter in orbit. Due to observations of intense radiation around black holes caused by infalling matter, we know accretion happens, so there must be turbulence leading to angular momentum transport. In accretion disks with large-scale ordered magnetic fields, one possible source of this turbulence is the magnetic RayleighTaylor (mRT) instability. The effects of this instability are frequently seen in the thin magnetically dominated accretion disk simulation I study and I will share how they affect the accretion rate of the system and the relevance of the mRT instability to angular momentum transport.

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Physics and Astronomy Colloquia Event - Ithaca College

Professor Fred Skiff; University of Iowa

Abstract: Hot plasmas have a large number of degrees of freedom. Generally in physics, a fundamental way to explore the degrees of freedom is through scattering. In plasma physics it is traditional to describe waves using fluid theory where the plasma degrees of freedom consist of a few collective modes with discrete dispersion relations w(k). However, experiments on wave scattering, for example on the ion acoustic wave, produce inconsistent results in the fluid model.Theoretically, even with the simplifications of a 1-D, low-frequency, electrostatic model where the electrons are treated as a neutralizing fluid, Vlasov-ion plasma actually supports an uncountable infinity ofmodes: the Case-Van-Kampen continuum. In weakly-collisional plasma, I am not sure what the degrees of freedom are theoretically. In this talk I will describe my efforts to develop a scattering theory for collective excitations in hot (Vlasov) and weakly-collisional plasma.It is a work in progress.

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Math Physics Seminar - Professor Fred Skiff | Physics and Astronomy | The University of Iowa - Iowa Now

The field of extrasolar planet research has advanced by leaps and bounds over the past fifteen years. To date, astronomers have relied on space-based and ground-based telescopes to confirm the existence of 4,566 exoplanets in 3,385 systems, with another 7,913 candidates awaiting confirmation. More importantly, in the past few years, the focus of exoplanet studies has slowly shifted from the process of discovery towards characterization.

In particular, astronomers are making great strides when it comes to the characterization of exoplanet atmospheres. Using the Gemini South Telescope (GST) in Chile, an international team led by Arizona State University (ASU) was able to characterize the atmosphere of a hot Jupiter located 340 light-years away. This makes them the first team to directly measure the chemical composition of a distant exoplanets atmosphere, a significant milestone in the hunt for habitable planets beyond our Solar System.

The teams study, which recently appeared in the scientific journal Nature, was led by Assistant Professor Michael Line of ASUs School of Earth and Space Exploration (SESE). He was joined by fellow SESE researchers and members of the Virtual Planetary Laboratory Team (part of NASAs Astrobiology Institute), the Centre for Exoplanets and Habitability (University of Warwick), and multiple universities worldwide.

For this study, Line and his team focused on WASP-77A b, a gas giant with a mass of 2.29 Jupiters that orbits very close to its Sun-like star (G-type). With an average distance of 0.024 AU, this hot Jupiter takes only 1.4 days to complete a single orbit of its star and experiences temperatures of upwards of 1093C (2,000F). The planet was spotted for the first time in 2012 by the Wide Angle Search for Planets (WASP) campaign using the Transit Method (aka. Transit Photometry).

This method consists of monitoring stars for periodic dips in luminosity, which are measured and timed to determine the size and orbital period of any planets orbiting the star. Sometimes, astronomers can observe light passing through the atmosphere of the transiting exoplanet, which allows them to obtain spectra and determine what chemicals are present in the planets atmosphere. This time, Prof. Line and his colleagues obtained spectra directly from WASP-77A b as it orbited its host star.

For the sake of their study, Line and his team hoped to obtain measurements on the atmospheric carbon and oxygen in WASP-77A bs atmosphere. The presence of these elements relative to hydrogen in hot Jupiters (relative to their host stars) is something astronomers are seeking, as it will provide insight into this strange class of exoplanet. In particular, astronomers hope to learn more about their formation and subsequent migration. As Prof. Line explained in a recent ASU News release:

Because of their sizes and temperatures, hot Jupiters are excellent laboratories for measuring atmospheric gases and testing our planet-formation theories. We needed to try something different to address our questions. And our analysis of the capabilities of Gemini South indicated that we could obtain ultra-precise atmospheric measurements.

In the past, Line and his team have been extensively involved in measuring the atmospheric compositions of exoplanets with the Hubble Space Telescope. Unfortunately, Hubbles instruments can only measure the presence of water (inferred from the presence of oxygen) in a planets atmosphere. Unfortunately, they cannot accurately measure the amounts of carbon compounds (such as carbon monoxide).

This time, Line and his colleagues turned to the 8.1-meter telescope at the Gemini South Observatory, which is operated by the National Science Foundations National Optical-Infrared Astronomy Research Laboratory (NOIRLab). Using the telescopes Immersion GRating INfrared Spectrometer (IGRINS), they were able to observe WASP-77A b directly and measure its near-infrared thermal glow.

From this, they were able to determine the presence and relative amounts of water vapor and carbon monoxide in the planets atmosphere. Said Line:

Trying to figure out the composition of planetary atmospheres is like trying to solve a crime with fingerprints. A smudged fingerprint doesnt really narrow it down too much, but a very nice, clean fingerprint provides a unique identifier to who committed the crime.

Whereas the Hubble Space Telescope was able to provide the team with one or two fuzzy fingerprints in the past, the IGRINS instrument on the Gemini South telescope provided the team with a full set of clear chemical signatures. From this, they were able to constrain the relative amounts of oxygen and carbon in the exoplanets atmosphere and its host star, all of which were in line with their expectations.

These results are not only a major technical achievement but also demonstrate how astronomers will be able to obtain ultra-precise measurements on the presence and abundances of various gases in exoplanet atmospheres. This is the key to exoplanet characterization, which allows astronomers to determine whether or not a planet can support life (as we know it). In essence, this study was a pathfinder demonstration that shows what will be possible in the coming years.

By the end of the decade, astronomers will have access to next-generation telescopes, including the James Webb Space Telescope (JWST) and the Nancy Grace Roman Space Telescope (RST). In addition, several ground-based observatories will come online in the near future, including the Extremely Large Telescope (ELT) and the Giant Magellan Telescope (GMT), both of which are currently under construction in the Atacama Desert in northern Chile. Said Line:

We are now at the point where we can obtain comparable gas abundance precisions to those planets in our own solar system. Measuring the abundances of carbon and oxygen (and other elements) in the atmospheres of a larger sample of exoplanets provides much needed context for understanding the origins and evolution of our own gas giants like Jupiter and Saturn.

If we can do this with todays technology, think about what we will be able to do with the up-and-coming telescopes like the Giant Magellan Telescope. It is a real possibility that we can use this same method by the end of this decade to sniff out potential signatures of life, which also contain carbon and oxygen, on rocky Earth-like planets beyond our own solar system.

Looking ahead, Line and the team plan to conduct these same types of measurements on many more exoplanets, eventually building up a sample of at least 15 atmospheric characterizations.They also anticipate many more exciting finds once next-generation telescopes become available. With their particular combination of spectrometers, coronographs, and/or adaptive optics, these observatories will conduct Direct Imaging studies that allow for exoplanet characterization like never before!

Further Reading: ASU, Nature

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Astronomers Measure the Atmosphere on a Planet Hundreds of Light-Years Away - Universe Today

Recent weeks have witnessed a series of medium-to-large-sized asteroids cross paths with Earths orbit. The largest of the pack asteroid 2004 UE is on track to make its closest approach to the planet Nov. 13. University of Illinois Urbana-Champaign astronomy professor and chair Leslie Looney spoke with News Bureau physical sciences editor Lois Yoksoulian about what researchers refer to as near Earth objects and how much of a threat they are to the planet.

What are near Earth objects, what are they composed of and how do we know?

Near Earth objects are meteoroids, asteroids or comets with orbits that bring them close to Earths orbit. They are the leftovers of our solar system formation process, which means they are the nearly pristine bits and pieces of ice and rocks from which the planets formed. We know their orbits from tracking them, and we know of their composition from examining their reflected and infrared light and by comparisons to objects that we have visited with space missions.

There seem to be a lot of large NEOs in Earths neighborhood in recent weeks. Is this unusual?

Over the last 20 years, NASA has dramatically increased the number of known NEOs from knowing of less than a thousand to nearly 28,000. The precise dimensions of NEOs can be difficult to resolve due to their small size and great distances. However, those estimated by NASA to be 140 meters or more along their longest axis most asteroids are potato-shaped, so their dimensions can be described as roughly spherical have been mandated by Congress to be classified as NEOs. The increase in the number of objects classified as NEOs was in part due to this mandate. Anything of this size could have a catastrophic impact on Earth, destroying cities with large losses of life. This awareness leads to more reporting of objects.

How do scientists spot and track NEOs?

We discover NEOs by taking pictures of the night sky over a night or over multiple nights, looking for something that moves compared with the stars or galaxies. The closer the NEO is to Earth, the faster it will move. With enough time, we can use these images to determine the objects orbit. Many new and exciting upcoming astronomical surveys will also map the night sky over many years to look for supernovae or other time-varying objects, so we expect to find even more objects over the next few decades.

At what size does a NEO become a concern?

Anything over 140 meters in diameter could cause major damage to cities or coasts, so any NEO with orbits that cross Earths orbit is classified as a potentially hazardous object. There are about 2,000 PHOs known today. None of them are likely to impact the planet in the next 100 years, but we still watch their orbits for any shifts. The orbital paths of NEOs that will be near Earth in more than 100 years cannot be predicted very well. However, it is important to note that large impacts have hit Earth in the past ask any dinosaur you meet and the planet will be hit by large impacts in the future. It is not a matter of if, but a matter of when. But dont panic. It is not likely to happen anytime soon.

Are there any ways we can deflect NEOs that come too close?

If we have an advanced warning of five to 10 years or so, deflecting a NEO should be easy. I am not talking about nuclear blasts or anything like that. Blowing up a NEO is probably the worst thing to do, since now you have many smaller rocks in the same orbit. That said, NASA will launch this month the Double Asteroid Redirection Test, or DART, which will test a kinetic impact with an asteroid. This planned high-speed impact is scheduled to occur in October, and will determine how effectively we can change an asteroid orbit.

There are many other methods, including a gravity tractor a spacecraft that nudges the asteroid using the spacecrafts mass or attached rockets. If our civilization wants to survive for the next 1,000 years, we have to figure this out.

Asteroid 2004 UE will reach its closest approach to Earth on Nov. 13. How do this objects size and trajectory compare to other identified NEOs throughout history?

Asteroid 2004 UE is pretty typical of a NEO. It is around 160 meters in diameter most are smaller, but many are bigger. Asteroid 2004 UE is not considered a safety concern since the closest approach to Earths orbit on Nov. 13 will be more than 30 times the Earth-moon distance. This happens frequently.

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A large asteroid will pass by Earth this week should we worry? - University of Illinois News

VAN 309, or online at Meeting ID: 931 1146 7821. Passcode: condmat

We will have 4 10 min presentations;

Until recently, non-circular core geometries(e.g., square or rectangular)of multimode fibers (MMFs) have not been investigated with wavefront shaping. In this research project, I perform wavefront shaping through MMFs using Lee Holography and concludethat both square and rectangular core MMFs present attractive frequency bandwidths when focusing light at the distal end of the MMF, enabling new experimental opportunities in photonics.

2D materials have great potential in electronic device applications such as FETs as well as in optoelectronic devices like semiconductor waveguides. In this short presentation we would learn about some of the methods commonly used to prepare 2D materials and heterostructures as well as investigate their properties in the visible and near-infrared spectrum.

Due to the limitations and expenses imposed by commercially available infrared equipment, research into the temperature and thickness dependent properties of 2 dimensional materials necessitates the production of a custom built cryogenic infrared microscope. This custom microscope needs to be developed using widely available parts, broadband for multiple possible use cases, and simple enough to be assembled without expertise due to the lack of documentation in this area

In order to innovate an analyze current detection methods of Volatile Organic Compounds, we have developed our own fitting program and system to detect compounds. Using gas spectroscopy, we will be able to improve detection with the end goal being in the PPB

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Condensed Matter Seminar - Undergraduate Seminar | Physics and Astronomy | The University of Iowa - Iowa Now

Esha Gupta Shares Her Love For Astronomy, Basketball With Fans ( Photo Credit Instagram )

Esha Gupta is currently busy shooting for two back-to-back web series including Invisible Woman and Ashram 3.

Taking some time off from her busy schedule, the actress recently took to Instagram stories where she revealed some of her most loved things to her fans. She shared that astronomy was her favourite subject in school and that she was always mesmerized by the extraterrestrial world and celestial bodies.

Esha Gupta also spoke about the actors whom she looked up to in the industry, she pointed out that Pankaj Tripathi and the late Irrfan Khan always found a place high on her list. She referred to them as part of the elite pack of performers. Ajay Devgn and Emraan Hashmi, with whom she worked in the 2017 film Baadshaho, were the stars she loved sharing screen space with.

Talking about her hobbies, the actress shared that she has diverse interests. While she loves playing sports like basketball and football, she also likes curling up in bed with a book for a reading session. In addition, she is very particular about fitness and more than Pilates or Yoga, Esha finds her groove in dance, as she considers it a complete workout.

Esha Guptas most loved book is F. Scott Fitzgeralds jazz-age saga The Great Gatsby. Croatian footballer Luka Modric who also plays for Spanish club Real Madrid is also among her favourites.

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Esha Gupta Reveals About Her Love For Astronomy, Basketball With Her Fans On Instagram - koimoi

The Hubble Space Telescope. Image: NASA

NASA is continuing work to resolve an issue that has suspended science operations on the Hubble Space Telescope. The science instruments entered a safe mode configuration on Oct. 25 after detecting a loss of specific data synchronisation messages.

The Hubble team is focusing its efforts to isolate the problem on hardware that commands the instruments and is part of the Science Instrument Command and Data Handling Unit. Specifically, the team is analysing the circuitry of the Control Unit, which generates synchronisation messages and passes them onto the instruments.

While analysing the Control Unit, the team is working to identify potential workarounds for the issue. These include possible changes to instrument flight software that could check for these lost messages and compensate for them without putting the instruments into safe mode. These workarounds would first be verified using ground simulators to ensure they work as planned.

Over the weekend of Oct. 30, the team prepared to turn on parts of the Near Infrared Camera and Multi Object Spectrometer (NICMOS) instrument to collect data on this issue, allowing the team to determine how frequently this problem occurs. Installed in 1997, NICMOS has been inactive since 2010, when the Wide Field Camera 3 became operational. NICMOS allowed the team to use an instrument to collect information on these lost messages while keeping the active instruments off as a safety precaution. Since NICMOS was recovered on Nov. 1, no additional synchronisation messages have been lost.

The team is now taking steps to recover Hubbles Advanced Camera for Surveys (ACS) instrument from safe mode and start collecting science with that instrument at the beginning of next week. The team will make the decision on Sunday after analysing the latest data. If a lost message is seen before then, the decision to activate ACS will also be revisited. The team is proceeding cautiously to ensure the safety of the instruments and avoid additional stresses on the hardware. Therefore, only ACS will be used in this capacity next week. ACS was selected as the first instrument to recover as it faces the fewest complications should a lost message occur.

Over the next week, the team will continue analysing the Control Unit design diagrams and data associated with the lost messages to determine what may have caused this problem. They will also be looking into potential instrument software changes that could help address it. Once the team better understands the frequency of the problem and has determined the time needed to implement possible software changes, they will discuss a plan for returning the other instruments to science operations.

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Engineers test workarounds to recover from Hubble synchronisation glitch Astronomy Now - Astronomy Now Online

ProfessorIonut Chifan; University of Iowa

Abstract: In this talk I will introduce a new class of groups, which we call textit{wreath-like products}. These groups are close relatives of the classical wreath products and arise naturally in the context of group theoretic Dehn filling. Unlike ordinary wreath products, many wreath-like products have strong fixed point properties including Kazhdan's property (T). In this paper, we establish several new rigidity results for von Neumann algebras of wreath-like products. In particular, we obtain the first continuum of property (T) groups whose von Neumann algebras satisfy Connes' rigidity conjecture and the first examples of W$^*$-superrigid groups with property (T). We also compute automorphism groups of von Neumann algebras of a wide class of wreath-like products; as an application, we show that for every finitely presented group $Q$, there exists a property (T) group $G$ such that $Out(L(G))cong Q$. This is based on new joint work with Adrian Ioana, Denis Osin and Bin Sun.

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Operator Theory Seminar - Professor Ionut Chifan, PhD | Physics and Astronomy | The University of Iowa - Iowa Now