Tag: astronomy

Webb engineers successfully deploy the telescope’s secondary mirror

2:50 pm

Engineers today confirmed that the secondary mirror for the James Webb Space Telescope has successfully deployed, its tripod structure unfolding and locking into place.

In addition the cover protecting the Mid-Infrared Instrument (MIRI) was successfully unlocked. The instrument’s science team did not open the cover yet because the telescope hasn’t yet cooled enough, its sun shield only in place for a day or so.

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Webb: Sun shield deployment completed

3:32 pm

Engineers today successfully completed the full deployment of the sun shield of the James Webb Space Telescope.

The unfolding and tensioning of the sunshield involved 139 of Webb’s 178 release mechanisms, 70 hinge assemblies, eight deployment motors, roughly 400 pulleys, and 90 individual cables totaling roughly one quarter of a mile in length. The team also paused deployment operations for a day to work on optimizing Webb’s power systems and tensioning motors, to ensure Webb was in prime condition before beginning the major work of sunshield tensioning.

The process took eight days, and was by far the most complex such remote deployment ever attempted by an unmanned spacecraft. The shield is now in place to shade Webb from sunlight and heat and thus allow it to observe very faint infrared objects billions of light years away.

Next comes the deployment of Webb’s secondary mirror, followed by the unfolding of its main mirror.

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Webb deployment resumes, with continuing success

9:50 am

After a day delay to assess the telescope’s earlier operation in space, engineers yesterday resumed the deployment of the James Webb Space Telescope’s sun shield.

First they began tensioning the shield’s first of five layers, completing that operation in about five and a half hours.

Next the engineers proceeded to tighten layers two and three, completing that task in about three hours.

Today they have begun tightening the last two layers. A live stream of this slow and relatively unexciting process (as long as nothing goes wrong) is available from NASA here.

Based on what has been done so far, it appears that the deployment of the sun shield, considered the most challenging part of Webb’s deployment, is going to complete successfully. While the unfolding and deployment of the mirror still must be done, getting the sun shield deployed eliminates one of the great concerns that has kept both astronomers and engineers awake nights for decades.

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The unfurling of Webb’s sun shield begins

5:18 pm

Engineers have begun the multi-day unfurling and deployment of the sun shield on the James Webb Space Telescope.

The first step is to deploy two booms on each side of the telescope that draw the shield itself outward.

The deployment of the first boom was held up several hours to give engineers time to make sure the protective covers had, in fact, rolled off to the side of the sunshade pallets as required.

“Switches that should have indicated that the cover rolled up did not trigger when they were supposed to,” NASA said in a blog post. “However, secondary and tertiary sources offered confirmation that it had.”

“The deployment of the five telescoping segments of the motor-driven mid-boom began around 1:30 p.m., and the arm extended smoothly until it reached full deployment,” NASA said.

Engineers then sent commands to deploy the second sunshade boom, which extended smoothly and locked in place at 10:13 p.m., finally giving Webb its iconic kite-like shape.

Next the shield has to be tightened in place, which will also separate and tighten in place the shield’s five layers. According to the schedule, the four layers will be tensioned today, with the fifth tomorrow.

The step-by-step deployment is outlined in detail here, and updates to the most recently completed step after it is finished.

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1st stage of Webb sun shield deployment completed

9:29 am

The deployment of the forward and aft pallets required to support the sun shield for the James Webb Space Telescope has apparently been successfully completed.

The link takes you to the website that outlines each step in Webb’s entire 30-day deployment sequence, and is updated to show you the next required step as the process continues. Though I have yet to see any official announcement, this page now shows that both pallets have successfully unfolded and that the next step is removal of the covers that have protected the sun shield membrene during assembly and launch.

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Deployment of Webb’s critical sunshield has begun

9:03 am

The deployment of the complex sunshield for the James Webb Space Telescope has successfully begun, and if all continues as planned, will continue for the next five days.

Early this afternoon the Webb mission operations team concluded the deployment of the first of two structures that hold within them Webb’s most unpredictable and in many ways complicated component: the sunshield.

The structures – called the Forward and Aft Unitized Pallet Structures – contain the five carefully folded sunshield membranes, plus the cables, pulleys, and release mechanisms that make up Webb’s sunshield. The team completed the deployment of the forward pallet at approximately 1:21 p.m. EST, after beginning the entire process about four hours earlier. The team will now move on to the aft pallet deployment.

Over the next five days the aft pallet must be deployed, along with a tower assembly that will raise the telescope itself away from the sunshield to better keep Webb cold. After this the deployment of the many additional parts of the shield will take place, a process that is probably the most complex in-space spacecraft deployment ever.

It is good news that so far all is proceeding as planned, and gives hope that all will continue to do so.

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Webb: Course correction burn and main antenna deployment both a success

2:11 pm

Over the weekend engineers for the James Webb Space Telescope successfully completed a course correction burn that put the telescope on route to is planned location a million miles from Earth.

They also successfully deployed the telescope’s main antenna.

Other steps completed on Webb’s first full day in space included the switch-on of temperature sensors and strain gauges on the telescope, used for monitoring Webb’s thermal and structural parameters, NASA said. The antenna release and first mid-course correction burn set the stage for the next step of Webb’s post-launch commissioning — the deployment and tensioning of the observatory’s tennis court-sized sunshield.

These next steps are likely the most risky part of the telescope’s deployment, as it involves the most moving parts and is the most complex. While similar such unfoldings have been done successfully many times before, they have also been the very prone to failure.

The sunshield must work however for Webb to operate. As an infrared telescope, it essentially detects heat, and if it is not well shielded from sunlight its images will be fogged.

The deployment is presently set to begin tomorrow.

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Webb successfully launched

8:13 am

Early this morning an Ariane 5 rocket successfully launched the James Webb Space Telescope from French Guiana.

The key moment that indicated the launch was success was, after Webb was deployed from the rocket’s upper stage, its solar panels deployed and the telescope began receiving power from them.

The launch itself was something that has been done by the Ariane 5 rocket many many times, without failure. Now comes the part of this operation that has never been done before.

Now “30 days of terror” begin, as JWST starts its career in space. First, it will take the space telescope 30 days to reach the start of its halo orbit at L2. On its way, the telescope must unfurl its 18 gold-plated beryllium mirror segments using 132 actuators. It will also have to deploy its five-layer, origami sunshield and cool down to below 50K (-223°C or -370°F) to begin the start of science operations in 2022.

NASA has a webpage that shows the step-by-step deployment, and allows you to see the status at any time during the next 30 days.

After almost twenty years of development and a budget that went 20x over its original estimate, let’s us all hope that Webb deploys properly and begins collecting data as intended. If it does, it will allow astronomers to make ground-breaking discoveries, and we shall gain a better idea of what lies hidden behind that black sky that surrounds us.

As for the 2021 launch race, this is the updated leader board:

49 China
31 SpaceX
22 Russia
7 Europe (Arianespace)

China will likely be the winner in the national rankings, 49 to 48 over the U.S. This was the 130th successful launch in 2021, only the second time in the history of space exploration that the world reached that number of launches in a single year.

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Webb telescope reaches launchpad on Ariane 5 + how to watch launch

9:14 am

The James Webb Space Telescope, stacked on top of Arianespace’s Ariane 5 rocket, has finally reached its launchpad in French Guiana after twenty years of development costing 20 times its original budget.

The launch itself is now scheduled for December 25, 2021 at 7:20 am (Eastern). It will be live streamed by both NASA (in English) and Arianespace (with options in English, French, or Spanish).

I have embedded below NASA’s feed. As always, expect NASA to pump you with lots of propaganda during its live stream.

When all is said and done, Webb has the chance to show us things about the universe we’ve never seen before. Optimized for deep space cosmology, it will provide us a window into the earliest moments of the universe’s existence. And is infrared capabilities will allow it to peer into many nearer places obscured by dust with a resolution unmatched by previous telescopes.

Keep your fingers crossed all goes as planned.
» Read more

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Astronomers detect 70 to 170 free floating exoplanets

11:03 am

The uncertainty of science: Astronomers today announced that they think they have detected from 70 to 170 exoplanets in a nearby star-forming region that are apparently free-floating, unattached to any star or solar system.

The astronomers also combined the vast number of images available in public astronomical archives with the new deep wide-field observations obtained with the best infrared and optical telescopes on the ground and in space. Using over 80,000 wide-field images adding up to around 100 terabytes and spanning 20 years, they identified at least 70, and up to as many as 170 of these Jupiter-sized planets, as members of the Upper Scorpius association among the background stars and galaxies.

If confirmed, this discovery more than doubles the number of free-floating planets known.

The discovery was made by first using the motion of the stars to pinpoint which ones belonged to the Upper Scorpius star-forming region. The astronomers then compared this data with past archival telescopic images.

Though intriguing, a great deal of skepticism of this discovery is required. The press release is very vague about some points. For example, no explanation is given on how they measured the mass of these objects to determine they were Jupiter-sized.

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ESA delays Webb launch one day due to weather

8:41 am

The European Space Agency (ESA) announced late yesterday that, due to “adverse weather conditions” in French Guiana, it has delayed the launch of the James Webb Space Telescope on an Ariane 5 rocket one day to December 25th.

The announcement also stated that the final launch readiness review also approved the launch, though no update has yet been issued on the ground control communications problem that had caused a two day delay last week.

Meanwhile, this story and its headline encapsulates the terror I think many astronomers presently feel about this telescope:

Why Astronomers Are “Crying and Throwing Up Everywhere” Over the Upcoming Telescope Launch

The sense is one of helpless panic among astronomers who want to use Webb. They know it will do really cutting edge science, but they also know that many things can go wrong, and the history of the telescope (ten years late and 20x overbudget) will likely make replacing it impossible.

And many things can go wrong. Below is NASA’s video showing the telescope’s complex unfolding, step-by-step, after launch.
» Read more

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Webb launch confirmed for December 24, 2021

9:01 am

Ten years late and twenty times over budget the European Space Agency (ESA) yesterday confirmed that the launch of NASA’s infrared James Webb Space Telescope is now scheduled for December 24, 2021.

The ESA announcement is only a couple of sentences long, and does not mention if engineers had solved the intermittent ground communications issue with the telescope. Further tweets from ESA and NASA also said nothing about the communication issue.

A final readiness review is set for December 21st where a final launch decision will be made.

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Webb launch delayed two days because of ground equipment issue

9:42 pm

After engineers at Arianespace’s French Guiana launch facility found an intermittent issue with ground equipment related to the Ariane 5 rocket launching the James Webb Space Telescope, it was decided to delay the launch two days to make sure the problem was resolved.

n a brief statement, NASA wrote on its website late Tuesday that the Webb team is “working a communications issue between the observatory and the launch vehicle system.”

Thomas Zurbuchen, associate administrator for NASA’s science mission directorate, said Tuesday that engineers found an “interface problem” in a system that communicates with Webb while it’s on top of the Ariane 5 rocket. “The way to think about it is it’s a ground support equipment thing,” Zurbuchen said Tuesday night in an interview with Spaceflight Now. “Basically, the data cables are dropping some frames.”

Technicians inside the Ariane 5 rocket’s final assembly building in Kourou have tried to diagnose the problem, but so far, haven’t been able to resolve it.

The December 24th target day date remains tentative, and could slip to December 25th, or even later, depending on how successful engineers are at fixing the issue.

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99.9% of all mass at center of Milky Way is found in central black hole

10:46 am

New measurements of the orbits of several stars circling the Milky Way’s central supermassive black hole, Sagittarius A* (pronounced A-star), have confirmed that 99.9% of all mass at the galaxy’s center is concentrated in that black hole.

Astronomers have measured more precisely than ever before the position and velocity of four stars in the immediate vicinity of the supermassive black hole that lurks at the center of the Milky Way, known as Sagittarius A* (Sgr A*) [1]. These stars — called S2, S29, S38, and S55 — were found to be moving in a way that shows that the mass in the center of the Milky Way is almost entirely due to the Sgr A* black hole, leaving very little room for anything else.

The measurements, which further refine the mass of Sagittarius A* as 4.3 million times the mass of the Sun, show that very little of this mass is found in the surrounding space as gas or dark matter. It is all in the black hole, which might also help explain why the Milky Way’s central black hole is so quiescent. It has very little gas or other stars to feed it and thus produce emissions.

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Conflict in Hubble constant continues to confound astronomers

9:56 am

The uncertainty of science: In reviewing their measurements of the Hubble constant using a variety of proxy distance tools, such as distant supernovae, astronomers recently announced that their numbers must be right, even though those numbers do not match the Hubble constant measured using completely different tools.

Most measurements of the current acceleration of the universe (called the Hubble constant, or H0) based on stars and other objects relatively close to Earth give a rate of 73 km/s/Mpc. These are referred to as “late-time” measurements [the same as confirmed by the astronomers in the above report]. On the other hand, early-time measurements, which are based on the cosmic microwave background emitted just 380,000 years after the Big Bang, give a smaller rate of 68 km/s/Mpc.

They can’t both be right. Either something is wrong with the standard cosmological model for our universe’s evolution, upon which the early-time measurements rest, or something is wrong with the way scientists are working with late-time observations.

The astronomers are now claiming that their late-time observations must be right, which really means there is either something about the present theories about the Big Bang that are fundamentally wrong and that our understanding of early cosmology is very incomplete, or the measurements by everyone are faulty.

Based on the number of assumptions used with both measurements, it is not surprising the results don’t match. Some of those assumptions are certainly wrong, but to correct the error will require a lot more data that will only become available when astronomers have much bigger telescopes of all kinds, in space and above the atmosphere. Their present tools on Earth are insufficient for untangling this mystery.

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SpaceX launches NASA X-ray telescope

9:17 am

Capitalism in space: SpaceX early this morning successfully launched NASA’s Imaging X-ray Polarimetry Explorer (IXPE), a small X-ray telescope designed to black holes and neutron stars.

The first stage, making its fifth flight, successfully landed on a drone ship in the Atlantic.

This launch, SpaceX’s 28th for 2021, extends once again the company’s all time record for the most launches in a year by a private company.

The leaders in the 2021 launch race:

46 China
28 SpaceX
21 Russia
6 Europe (Arianespace)
5 ULA
5 Rocket Lab

China’s lead over the U.S, in the national rankings has now shrunk to 46 to 45. The launch was the 121st in 2021, making this year tied as the seventh most active year in the history of space, a ranking that is sure to go up before the end of the year.

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Hubble resumes full science operations

2:35 pm

Engineers have now successfully reactivated the Hubble Space Telescope’s second spectrograph, so that the telescope is now fully operational for the first time since it went into safe mode on October 25th.

NASA’s Hubble Space Telescope team recovered the Space Telescope Imaging Spectrograph on Monday, Dec. 6, and is now operating with all four active instruments collecting science. The team has still not detected any further synchronization message issues since monitoring began Nov. 1.

The team will continue work on developing and testing changes to instrument software that would allow them to conduct science operations even if they encounter several lost synchronization messages in the future. The first of these changes is scheduled to be installed on the Cosmic Origins Spectrograph in mid-December. The other instruments will receive similar updates in the coming months.

Essentially, they are modifying the telescope’s software so that it will not shut down should it “encounter several lost synchronization messages.” As the engineers have never fully explained this issue, I suspect this is a work-around to ignore an issue that in the past they would have taken more seriously. Now they are doing a cost-benefit analysis, and have decided that ignoring some of these messages is better than fixing them. It might even be impossible to do so.

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Astronomers discover galaxy with no dark matter

3:46 pm

The uncertainty of science: Astronomers have detected a galaxy about 250 million light years away that shows no evidence of any dark matter, a phenomenon that defies the accepted theories about dark matter.

The galaxy in question, AGC 114905, is about 250 million light-years away. It is classified as an ultra-diffuse dwarf galaxy, with the name ‘dwarf galaxy’ referring to its luminosity and not to its size. The galaxy is about the size of our own Milky Way but contains a thousand times fewer stars. The prevailing idea is that all galaxies, and certainly ultra-diffuse dwarf galaxies, can only exist if they are held together by dark matter.
Galaxy AGC 114905

The researchers collected data on the rotation of gas in AGC 114905 for 40 hours between July and October 2020 using the VLA telescope. Subsequently, they made a graph showing the distance of the gas from the center of the galaxy on the x-axis and the rotation speed of the gas on the y-axis. This is a standard way to reveal the presence of dark matter. The graph shows that the motions of the gas in AGC 114905 can be completely explained by just normal matter.

“This is, of course, what we thought and hoped for because it confirms our previous measurements,” says Pavel Mancera Piña. “But now the problem remains that the theory predicts that there must be dark matter in AGC 114905, but our observations say there isn’t. In fact, the difference between theory and observation is only getting bigger.”

The evidence for dark matter in almost all galaxies is the motion of gas and stars in the outer perimeter. Routinely they move faster than expected based merely on visible ordinary matter. To account for the faster speed, astronomers beginning in the late 1950s invented dark matter, an invisible material with a mass sufficient to increase the speeds of objects and gas in the outer regions of galaxies.

That increasingly astronomers are finding galaxies with no evidence of dark matter, based on rotation speeds, only makes this mystery all the more baffling.

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Engineers recover a third Hubble instrument

2:39 pm

Engineers have now reactivated a third instrument on the Hubble Space Telescope, bringing the telescope very close to full operations again with only one instrument, a spectrograph, still in safe mode.

The Hubble Space Telescope team recovered the Cosmic Origins Spectrograph instrument on Sunday, Nov. 28, moving the telescope further toward full science operations. Three of Hubble’s four active instruments are now collecting science data once again.

The team also continued work on developing and testing changes to instrument software that would allow them to conduct science operations even if they encounter several lost synchronization messages in the future. Those changes would first be installed on the Cosmic Origins Spectrograph once they’re completed and tested within a few weeks. Hubble’s other instruments would also receive similar changes. The team has not detected further synchronization message issues since monitoring began Nov. 1.

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Engineers: Webb undamaged by “incident”, ready for December 22nd launch

9:46 am

Arianespace engineers have confirmed after testing that the James Webb Space Telescope was undamaged by “incident” that occurred during stacking, and have okayed the resumption of the telescope’s preparation for launch.

On Wednesday, Nov. 24, engineering teams completed these tests, and a NASA-led anomaly review board concluded no observatory components were damaged in the incident. A “consent to fuel” review was held, and NASA gave approval to begin fueling the observatory. Fueling operations will begin Thursday, Nov. 25, and will take about 10 days.

The launch is now set for December 22nd.

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Second camera on Hubble returned to science operations

10:35 am

Engineers working to reactivate the instruments on the Hubble Space Telescope have successfully brought a second camera out of safe mode.

NASA continues bringing the Hubble Space Telescope back to normal science operations, most recently recovering the Wide Field Camera 3 instrument Sunday, Nov. 21. This camera will be the second of Hubble’s instruments, after the Advanced Camera for Surveys, to resume science after suspending the spacecraft’s observations Oct. 25. The Wide Field Camera 3’s first science observation since the anomaly will be Nov. 23.

The team chose to restore the most heavily used Hubble instrument, the Wide Field Camera 3, which represents more than a third of the spacecraft’s observing time. Engineers also began preparing changes to the instrument parameters, while testing the changes on ground simulators. These changes would allow the instruments to handle several missed synchronization messages while continuing to operate normally if they occur in the future. These changes will first be applied to another instrument, the Cosmic Origins Spectrograph, to further protect its sensitive far-ultraviolet detector. It will take the team several weeks to complete the testing and upload the changes to the spacecraft.

The telescope’s other instruments remain in safe mode as the engineers continue to investigate the problem that caused the shut down on October 25th.

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Webb launch delayed four days because of “incident” during stacking

2:18 pm

NASA management has decided to delay the launch of the James Webb Space Telescope for four days while engineers investigate whether an “incident” that occurred during the telescope’s stacking on top of an Ariane 5 rocket could have long term consequences.

Technicians were preparing to attach Webb to the launch vehicle adapter, which is used to integrate the observatory with the upper stage of the Ariane 5 rocket. A sudden, unplanned release of a clamp band – which secures Webb to the launch vehicle adapter – caused a vibration throughout the observatory.

A NASA-led anomaly review board was immediately convened to investigate and instituted additional testing to determine with certainty the incident did not damage any components. NASA and its mission partners will provide an update when the testing is completed at the end of this week.

The launch had been scheduled for December 18th. They have now pushed it back to December 22nd.

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Hubble operations contract extended to 2026, even as engineers work to fix it

3:10 pm

NASA announced today that it has extended the contract for operating the Hubble Space Telescope through 2026, even as it also provided an update on the effort of engineers to bring all the telescope’s science instruments out of safe mode.

[T]he agency has awarded a sole source contract extension to the Association of Universities for Research in Astronomy (AURA) in Washington for continued Hubble science operations support at the Space Telescope Science Institute (STScI) in Baltimore, which AURA operates for NASA. The award extends Hubble’s science mission through June 30, 2026, and increases the value of the existing contract by about $215 million (for a total of about $2.4 billion).

…Currently, the spacecraft team at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, is investigating an issue involving missed synchronization messages that caused Hubble to suspend science observations Oct. 25. One of the instruments, the Advanced Camera for Surveys, resumed science observations Nov. 7, and continues to function as expected. All other instruments remain in safe mode.

During the week of Nov. 8, the Hubble team identified near-term changes that could be made to how the instruments monitor and respond to missed synchronization messages, as well as to how the payload computer monitors the instruments. This would allow science operations to continue even if several missed messages occur. The team has also continued analyzing the instrument flight software to verify that all possible solutions would be safe for the instruments.

In the next week, the team will begin to determine the order to recover the remaining instruments. The team expects it will take several weeks to complete the changes for the first instrument.

It appears that it is going to take some time to bring all the instruments back in line, considering that they are fixing the instruments one-by-one, in sequence, and that the first fix is taking weeks. Hopefully as they get each instrument back they will be able to move faster once they know what works.

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Hubble camera back in operation

2:16 pm

Good news! As engineers work to fix the problem that caused the Hubble Space Telescope to shut down on October 25th, they have now successfully returned Hubble’s most important camera back to doing science.

The Hubble team successfully recovered the Advanced Camera for Surveys instrument Nov. 7. The instrument has started taking science observations once again. Hubble’s other instruments remain in safe mode while NASA continues investigating the lost synchronization messages first detected Oct. 23. The camera was selected as the first instrument to recover as it faces the fewest complications should a lost message occur.

This success strongly suggests they have pinpointed the software issue that caused the shutdown, and can now step-by-step reactivate all the other instruments in the coming week.

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New catalog of 90 gravitational wave detections published

9:24 am

The scientists operating the world’s three gravitational wave detectors today released a new catalog of all their detections, totaling 90 with 35 never before published.

All signals come from merging black holes and neutron stars. The new catalog contains some surprises, such as an unusual neutron-star–black-hole merger, a massive black hole merger, and binary black holes revealing information about their spins.

…The researchers have also published two papers accompanying their new catalog today. One looks at what the events can tell us about the population of compact objects in our Universe, how often they merge, and how their masses are distributed. In the other paper the researchers employed the gravitational waves to better understand the expansion history of the cosmos by measuring the Hubble constant.

Because of the tiny sample so far detected, these generalized results cannot be taken too seriously, though they do give hints at the larger context.

All three observatories are now undergoing upgrades, and will resume operations in a few weeks.

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Astronomers release fantasy proposals for government telescopes in the 2020s

8:54 am

The astronomical community today released its newest decadal survey, a outline of what major new telescope projects that community recommends the federal government should fund for the next ten years.

More details here.

This is I think the seventh such decadal survey since the first in the early 1960s. In the past these surveys prompted the construction of numerous space telescopes, such as the Hubble Space Telescope, the James Webb Space Telescope, and many others. Until 2000 these survey were enormously influential, which is why space-based astronomy boomed in the 1980s and 1990s.

Now I call it a fantasy because I think it unlikely that most of its proposals — especially the space-based projects — will see fruition, based on the recent history in this century. For example, the 2001 survey recommended the James Webb Space Telescope among many other recommendations. The cost overruns of that project however eventually caused almost all the other space-based proposals to be cancelled, not only in the 2000s but in the 2010s as well. Furthermore, the 2010 survey called for the building of WFIRST, another Webb-like big space telescope that is now called the Roman Telescope, and that project’s high cost and complexity has further forced the elimination of almost all other new space telescopes. Nor has Roman been built and launched in the 2010s as proposed. It is still under development, with the same kinds of cost orverruns and delayed seen with Webb, which means in the 2020s most of the new proposals in this latest decadal survey will have to take a back seat to it, and will likely never get built.

Prove of my analysis is in the report’s press release:

The first mission to enter this program should be an infrared/optical/ultraviolet (IR/O/UV) telescope — significantly larger than the Hubble Space Telescope — that can observe planets 10 billion times fainter than their star, and provide spectroscopic data on exoplanets, among other capabilities. The report says this large strategic mission is of an ambitious scale that only NASA can undertake and for which the U.S. is uniquely situated to lead. At an estimated cost of $11 billion, implementation of this IR/O/UV telescope could begin by the end of the decade, after the mission and technologies are matured, and a review considers it ready for implementation. If successful, this would lead to a launch in the first half of the 2040 decade. [emphasis mine]

Proposing something that won’t be built for two decades is absurd. And the cost is even more absurd, as it is ten times what Hubble cost and seems more designed as a long term jobs program where nothing will get built but money will continue to pour in endlessly to the contractors and astronomers hired. That is what Webb and Roman essentially became.

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Astronomers detect water in the very very early universe

9:14 am

The uncertainty of science: Using the ALMA telescope in Chile, astronomers have detected the molecules of water and carbon monoxide in a galaxy thought to have formed only 780 million years after the Big Bang.

SPT0311-58 is actually made up of two galaxies and was first seen by ALMA scientists in 2017 at its location, or time, in the Epoch of Reionization. This epoch occurred at a time when the Universe was just 780 million years old—roughly 5-percent of its current age—and the first stars and galaxies were being born. Scientists believe that the two galaxies may be merging, and that their rapid star formation is not only using up their gas, or star-forming fuel but that it may eventually evolve the pair into massive elliptical galaxies like those seen in the Local Universe.

“Using high-resolution ALMA observations of molecular gas in the pair of galaxies known collectively as SPT0311-58 we detected both water and carbon monoxide molecules in the larger of the two galaxies. Oxygen and carbon, in particular, are first-generation elements, and in the molecular forms of carbon monoxide and water, they are critical to life as we know it,” said Sreevani Jarugula, an astronomer at the University of Illinois and the principal investigator on the new research. “This galaxy is the most massive galaxy currently known at high redshift, or the time when the Universe was still very young. It has more gas and dust compared to other galaxies in the early Universe, which gives us plenty of potential opportunities to observe abundant molecules and to better understand how these life-creating elements impacted the development of the early Universe.”

Need I say that there are many uncertainties with this result, including the assumption that the universe is only 780 million years old at location of this galaxy. That age is extrapolated from the galaxy’s red shift, a link that depends on some uncertain assumptions. Moreover, the discovery of these molecules so soon after the theorized Big Bang is unexpected. Cosmologists had assumed that at this early age the universe wasn’t old enough yet to form galaxies with such complex molecules.

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Hubble still in safe mode

9:05 am

NASA released a new but relatively terse update on November 1st describing the status of the Hubble Space Telescope, which has been in safe mode since October 25th.

Hubble’s science instruments issued error codes at 1:46 a.m. EDT Oct. 23, indicating the loss of a specific synchronization message. This message provides timing information the instruments use to correctly respond to data requests and commands. The mission team reset the instruments, resuming science operations the following morning.

At 2:38 a.m. EDT, Oct. 25, the science instruments again issued error codes indicating multiple losses of synchronization messages. As a result, the science instruments autonomously entered safe mode states as programmed.

Mission team members are evaluating spacecraft data and system diagrams to better understand the synchronization issue and how to address it. They also are developing and testing procedures to collect additional data from the spacecraft. These activities are expected to take at least one week.

In other words, the engineers presently do not understand the problem, and are working at pinpointing its cause.

This is not a “glitch”. If used properly that word really refers to something that is akin to a short burp in operations. Hubble has been shut down now for ten days, and will remain so for at least one more week. This is a serious problem that remains unsolved.

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Evidence from nearby white dwarfs suggest rocky exoplanets are alien to Earth

10:15 am

The uncertainty of science: Evidence from 23 white dwarfs, all located less than 650 light years from Earth, suggest that the make-up of rocky exoplanets are likely very alien to Earth, with minerals and chemistry that is found nowhere in our solar system.

They found that these white dwarfs have a much wider range of compositions than any of the inner planets in our solar system, suggesting their planets had a wider variety of rock types. In fact, some of the compositions are so unusual that Putirka and Xu had to create new names (such as “quartz pyroxenites” and “periclase dunites”) to classify the novel rock types that must have existed on those planets.

“While some exoplanets that once orbited polluted white dwarfs appear similar to Earth, most have rock types that are exotic to our solar system,” said Xu. “They have no direct counterparts in the solar system.”

Putirka describes what these new rock types might mean for the rocky worlds they belong to. “Some of the rock types that we see from the white dwarf data would dissolve more water than rocks on Earth and might impact how oceans are developed,” he explained. “Some rock types might melt at much lower temperatures and produce thicker crust than Earth rocks, and some rock types might be weaker, which might facilitate the development of plate tectonics.”

The data from the white dwarfs is believed to be the leftover material of exoplanets that were absorbed by the star, sometime in the far past.

First, this result should not be a surprise. To even think for a second that planets in other solar systems would be similar to the planets in our solar system is unrealistic. Even in our solar system we have found that practically every single body — planets, moons, asteroids, comets — is remarkably unique. Other solar systems are sure to be even more alien.

Second, the result here is somewhat uncertain. The scientists were not gathering data of actual exoplanets, but what is believed to be the remains that had been swallowed by the stars. The scientists then extrapolated backwards to come up with these alien rock types. The result, while very suggestive, must be taken with some skepticism.

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Astronomers: If there are artificial Dyson spheres out there, we can detect them

8:55 am

In a preprint science paper published on October 26, 2021, astronomers review the impact a Dyson sphere might have on its central star and conclude that modern astronomical instruments should be able to identify these changes. From the abstract:

The search for signs of extraterrestrial technology, or technosignatures, includes the search for objects which collect starlight for some technological use, such as those composing a Dyson sphere. These searches typically account for a star’s light and some blackbody temperature for the surrounding structure. However, such a structure inevitably returns some light back to the surface of its star, either from direct reflection or thermal re-emission. In this work, we explore how this feedback may affect the structure and evolution of stars, and when such feedback may affect observations. We find that in general this returned light can cause stars to expand and cool. Our MESA models show that this energy is only transported toward a star’s core effectively by convection, so low mass stars are strongly affected, while higher mass stars with radiative exteriors are not. Ultimately, the effect only has significant observational consequences for spheres with very high temperatures (much higher than the often assumed ~300 K) and/or high specular reflectivity. Lastly, we produce color-magnitude diagrams of combined star-Dyson sphere systems for a wide array of possible configurations.

A plain-language description of the paper can be found here, which summarizes this work as follows:

This study shows that Dyson spheres can result in measurable changes to stellar properties. Megastructures have long been confined to science fiction, imagination and certain video games. However, if there are indeed Dyson spheres out there waiting to be found, we could soon be in a position to find them.

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