Tag: astronomy

Astronomers claim to have discovered most powerful supernova ever

9:38 pm

The uncertainty of science: Astronomers have now calculated that a supernova that was spotted in 2016 was possibly the brightest ever detected, and might have been caused by the merger of two massive stars, each about sixty times as massive as the Sun.

SN 2016aps was discovered by the Panoramic Survey Telescope and Rapid Response System (Pan- STARRS) Survey for Transients on February 22, 2016 with an apparent magnitude of 18. Also known as PS16aqy, the explosion occurred in a low-mass galaxy some 3.1 billion light-years from Earth.

University of Birmingham’s Dr. Matt Nicholl and colleagues believe SN 2016aps could be an example of an extremely rare ‘pulsational pair-instability’ supernova, possibly formed from two massive stars that merged before the explosion. Such an event so far only exists in theory and has never been confirmed through astronomical observations.

…The researchers observed SN 2016aps for two years, until it faded to 1% of its peak brightness. Using these measurements, they calculated the mass of the supernova was between 50 to 100 solar masses. Typically supernovae have masses of between 8 and 15 solar masses.

They theorize that the supernova became especially bright when the explosion collided with a gas shell that already surrounded both stars.

Lots of assumptions and guesswork here, based on a tiny amount of data. The biggest lack is that they don’t have any observations of the star (or stars) prior to the supernova, so any theory about what those stars were like is exactly that, a theory.

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Earth-sized exoplanet in habitable zone found in old Kepler data

10:25 am

A review of the data produced by the space telescope Kepler, now retired, has discovered an exoplanet about the same size as Earth and also located in the habitable zone that had been missed previously by software.

Scientists discovered this planet, called Kepler-1649c, when looking through old observations from Kepler, which the agency retired in 2018. While previous searches with a computer algorithm misidentified it, researchers reviewing Kepler data took a second look at the signature and recognized it as a planet. Out of all the exoplanets found by Kepler, this distant world – located 300 light-years from Earth – is most similar to Earth in size and estimated temperature.

This newly revealed world is only 1.06 times larger than our own planet. Also, the amount of starlight it receives from its host star is 75% of the amount of light Earth receives from our Sun – meaning the exoplanet’s temperature may be similar to our planet’s as well. But unlike Earth, it orbits a red dwarf. Though none have been observed in this system, this type of star is known for stellar flare-ups that may make a planet’s environment challenging for any potential life.

A number of Earth-like planets have been found around red dwarf stars. Whether life could evolve in such places is entirely unknown. Red dwarfs are small, and would have likely formed in a nebula cloud with a dearth of many elements and materials needed for life. Moreover, because they are also so dim, the habitable zone is very near the star, meaning that, as the article mentions, strong flares are more dangerous.

At the same time, red dwarfs are the most common star, and the most long-lived, capable of burning for tens of billions of years. With enough time and numbers anything is still possible.

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Confirmed: Comet ATLAS has broken apart

8:47 am

Astronomers have now confirmed the fact that Comet ATLAS has broken into several pieces, and will not put on a spectacular sky show this coming May.

Just a month ago, it looked like the icy wanderer, officially known as C/2019 Y4 Atlas, might put on a dazzling sky show around the time of its closest approach to the sun, or perihelion, which occurs on May 31.

But relatively lackluster behavior soon dimmed such hopes. And optimism surrounding the comet is now pretty much extinguished, for it’s no longer in one piece. Comet Atlas “has shattered both its and our hearts,” astrophysicist Gianluca Masi, the founder and director of the Virtual Telescope Project in Italy, said in an emailed statement on Sunday (April 12). “Its nucleus disintegrated, and last night I could see three, possibly four main fragments.”

A nice picture of the break-up can be seen here.

We are due for another great comet, like Comet Hale-Bopp in the late 1990s. Unfortunately, Comet ATLAS won’t be that comet.

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Universe’s expansion rate found to differ in different directions

9:54 am

The uncertainty of science: Using data from two space telescopes, astronomers have found that the universe’s expansion rate appears to differ depending on the direction you look.

This latest test uses a powerful, novel and independent technique. It capitalizes on the relationship between the temperature of the hot gas pervading a galaxy cluster and the amount of X-rays it produces, known as the cluster’s X-ray luminosity. The higher the temperature of the gas in a cluster, the higher the X-ray luminosity is. Once the temperature of the cluster gas is measured, the X-ray luminosity can be estimated. This method is independent of cosmological quantities, including the expansion speed of the universe.

Once they estimated the X-ray luminosities of their clusters using this technique, scientists then calculated luminosities using a different method that does depend on cosmological quantities, including the universe’s expansion speed. The results gave the researchers apparent expansion speeds across the whole sky — revealing that the universe appears to be moving away from us faster in some directions than others.

The team also compared this work with studies from other groups that have found indications of a lack of isotropy using different techniques. They found good agreement on the direction of the lowest expansion rate.

More information here.

The other research mentioned in the last paragraph in the quote above describes results posted here in December. For some reason that research did not get the publicity of today’s research, possibly because it had not yet been confirmed by others. It now has.

What this research tells us, most of all, is that dark energy, the mysterious force that is theorized to cause the universe’s expansion rate to accelerate — not slow down as you would expect– might not exist.

Update: I’ve decided to embed, below the fold, the very clear explanatory video made by one of the scientists doing that other research. Very helpful in explaining this very knotty science.

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Comet ATLAS appears to be breaking apart

9:40 am

Comet ATLAS, which astronomer hope could be the brightest comet in decades, is unfortunately showing evidence of breaking up, which if so could short circuit any spectacular comet show.

In a recent Astronomical Telegram, astronomers Quanzhi Ye (University of Maryland) and Qicheng Zhang (Caltech) report that photographs taken on April 2nd and April 5th of the comet revealed a marked change in the appearance of its core or pseudo-nucleus from starlike and compact to elongated and fuzzy. A second team of astronomers led by I. A. Steele (Liverpool John Moores University) confirmed the discovery. This change in appearance is “consistent with a sudden decline or cessation of dust production, as would be expected from a major disruption of the nucleus,” wrote Zhang and Ye.

An elongated nucleus is often a bad sign and could mean the comet’s headed for disintegration much like what happened to Comet Elenin (C/2010 X1) prior to its September 2011 perihelion passage when its core crumbled and the object rapidly dissipated. Addition evidence of ATLAS’s breakup comes from an unexpected shift in the direction of its orbital motion caused by “non-gravitational” forces. Fragmentation exposes fresh ice to sunlight which quickly vaporizes. The expanding gases act like a natural rocket engine and gently push the comet from its appointed path.

The article outlines in detail how bright ATLAS could become, because of its size and orbit and proximity to Earth as it passes closest to the Sun in late May. Assuming it does not disintegrate, it could end up brighter than Venus. Or not. Predicting the eventual brightness of a newly discovered comet is more guesswork than science. That the comet might be falling apart suggests its eventually brightness will be less that hoped.

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Big sections break off of interstellar Comet 2I/Borisov

9:23 am

The uncertainty of science: New observations of the interstellar Comet 2I/Borisov as it exits our solar system indicate that large fragments have recently broken from it, and that the comet might possibly be on the verge of breaking up.

Astronomers have seen evidence of two fragments, but the data suggests these are relatively small compared to the entire comet. On the other hand,

Before perihelion, Jewitt’s analysis of Hubble images showed that Comet Borisov is much smaller than had been thought. The comet’s nucleus is not directly visible, but in the January 10th Astrophysical Journal Letters, Jewitt put its diameter between 0.4 and 1 kilometer. That’s small enough that solar vaporization of surface ices on the side facing the Sun could spin up its rotation beyond gravity’s ability to hold it together.

However, the comet’s size is tricky to estimate, as its surface appears to be emitting so much gas and dust that it obscures the nucleus. The fragment that Jewitt observed is about as bright as the comet itself, but because its surface is so icy and active, he thinks the fragment’s mass is less than 1% of the whole comet. That would make the split more like a side mirror dropping off a car than a car falling apart. Why the fragment split from the comet is unclear, but possibilities include thermal vaporization after new material was exposed, as well as the force from the comet’s spin if it’s spinning as fast as Jewitt suggests.

Whether the comet is about to break up remains unknown. Wouldn’t it be nice if someone was racing to put a mission together to visit it?

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TMT protesters abandon camp due to Wuhan virus fears

9:14 am

The protesters who have been blocking construction of the Thirty Meter Telescope (TMT) on Mauna Kea in Hawaii have abandoned their camp due to fears of COVID-19.

Though this gives the consortium an opportunity to begin construction, don’t expect it. Based on info I’ve gotten from within the astronomy community (most of which is liberal and thus very focused on identity politics), the consortium that wants to build TMT is torn over these protests, with many astronomers sympathetic to the protesters’ false claims of bigotry and religious oppression.

TMT will not be built in Hawaii. Whether it is built at all remains an open question.

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New radio telescope discovers many new Fast Radio Bursts

4:01 pm

A new radio telescope in Canada, designed to detect the mysterious and as-yet unexplained Fast Radio Bursts (FRB), has in the past year raised the total of known FRBs from 30 to 700, including nine repeating bursts.

This confirms an earlier very preliminary analysis that there were two different types of bursts, those that repeat and those that don’t.

Warning: It is very dangerous to take these results too seriously. A lot of uncertainty exists, including some basic facts about the bursts.

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Webb telescope further delayed by COVID-19

10:38 am

As part of its decision to shut down most of the agency’s operations due to fear of the COVID-19 virus, NASA’s has suspended all work on the James Webb Telescope, further delaying this much delayed space telescope.

The follow-on to the popular Hubble Space Telescope [Ed: a NASA lie that is not true], years late and billions over budget, it was on track for launch in March 2021, though some NASA officials were hinting there might be another delay. Today’s action almost certainly assures it. “The James Webb Space Telescope team … is suspending integration and testing operations. Decisions could be adjusted as the situation continues to unfold over the weekend and into next week. The decision was made to ensure the safety of the workforce. The observatory remains safe in its cleanroom environment.” — NASA

I must repeat this incessantly, as it appears too many modern space reporters are very ignorant about their own field. Webb is not a” follow-on to Hubble.” Astronomers made the decision in the late 1990s to build an infrared space telescope instead, which is what Webb is. For more than a decade they, and NASA, lied to the public about this, claiming Webb was a better version of Hubble, in order to garner support for building Webb.

I have been calling NASA on lie this since 2008, when I wrote The Universe in a Mirror, which I think eventually forced the agency to stop doing it. It is shameful however for a reporter now, in 2020, to still spread it.

As for Webb, this decision by NASA will certainly delay it again. The project is already fourteen years behind schedule, with its budget ballooning from $500 million to about $10 billion. All told, a perfect example of government in action.

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Comet C/2019 ATLAS brightening

4:42 pm

Comet ATLAS, discovered in 2019 by a telescopic survey looking for near Earth asteroids, is brightening more than expected as it approaches the Sun, and could by May be visible to the naked eye.

Jonathan Shanklin, Director of the British Astronomical Association’s Comet Section, reports that the current comet, C/2019 Y4, brightened quite rapidly in mid February, and adds “as of March 11 there is no sign of a slowdown in the rate of brightening. It is already visible in large binoculars . . . The uncertainty in brightness at the time of perihelion is large, though the worst case indicator is 2nd magnitude. It will remain well placed for UK observers into May and could become a prominent object.”

If 2nd magnitude is the dimmest they presently expect, this comet will be one of the brightest objects in the sky come May. Stay tuned!

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An exoplanet where it rains iron

10:12 am

Astronomers have discovered an exoplanet 640 light years away hot enough for iron to be vapor in the atmosphere and to condense out as rain.

The high-resolution spectrum reveals lots of iron vapor within the sliver of atmosphere undergoing the transition from day to night. However, this iron vapor signature is missing from the sliver of atmosphere transitioning from night to day. The astronomers think this happens because strong winds push iron vapor to the nightside, where it cools and condenses into clouds.

“This planet has a twilight zone at a temperature close to the iron condensation temperature,” Ehrenreich explains, “so the change in atmospheric composition (with iron vs. without iron) is occurring right where we are able to observe.”

Because the planet is a gas giant, there’s no surface onto which the droplets can fall, says coauthor Nuno Santos (University of Porto, Portugal). But the planet’s gravity likely pulls the clouds downward, enveloping the nightside in iron fog. The global winds then push the clouds and fog onto the dayside, where the vaporization-condensation cycle repeats again.

Very exotic, and alien, and I guarantee it is probably far more alien than we so far can guess.

You can find out more in this second more detailed article.

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Astronomers more precisely estimate the diameter of neutron stars

10:53 am

Using several different techniques, astronomers now estimate that the typical neutron star will have a diameter of 11 kilometers, or about 7 miles.

What is significant about this new estimate is that if that neutron star happens to be orbiting a black hole and get pulled into it, it will be swallowed whole instead of being ripped apart.

Their results, which appeared in Nature Astronomy today, are more stringent by a factor of two than previous limits and show that a typical neutron star has a radius close to 11 kilometers. They also find that neutron stars merging with black holes are in most cases likely to be swallowed whole, unless the black hole is small and/or rapidly rotating. This means that while such mergers might be observable as gravitational-wave sources, they would be invisible in the electromagnetic spectrum.

In other words, such cataclysmic events would be largely invisible to observers.

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Japan suspends funding to TMT

9:33 am

The Japanese government has confirmed that it has suspended payment of its annual contribution to the budget of the Thirty Meter Telescope (TMT) because of the project’s inability to begin construction on Mauna Kea in Hawaii.

Japanese astronomers strongly prefer placing TMT on Mauna Kea because it is relatively close to Japan, unlike the proposed replacement site in the Grand Canary Islands in the Atlantic.

I would say this is the next nail in the coffin for TMT in Hawaii. The National Science Foundation (NSF) has money to fund construction of a big telescope for U.S. astronomers, but has not been able to decide on whether to give the money to TMT, or to the Giant Magellan Telescope (GMT), already under construction in Chile, or to both.

Astronomers have been lobbying for dual funding, using the argument that the two telescopes are in the opposite north and south hemispheres. Moving TMT to the Grand Canaries, at a higher latitude than Hawaii, strengthens this argument. With the apparent exit of Japan it could be that the way is now cleared to give up on Hawaii and for TMT to make the move to a more welcoming site.

Hawaii’s protesters, supported by the state’s Democratically-controlled government, will of course celebrate. What they will be celebrating however will be the death-knell of science in Hawaii.

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Birth of a planetary nebula

8:49 am

Beginnings of a planetary nebula

Astronomers, using the Atacama Large Millimeter/submillimeter Array (ALMA) telescope in Chile have created a multi-spectral radio image of a dying star in its very initial stages of becoming a beautiful planetary nebula.

[Using ALMA,] the team obtained a very detailed view of the space around W43A. “The most notable structures are its small bipolar jets,” says Tafoya, the lead author of the research paper published by the Astrophysical Journal Letters. The team found that the velocity of the jets is as high as 175 km per second, which is much higher than previous estimations. Based on this speed and the size of the jets, the team calculated the age of the jets to be less than a human life-span.

“Considering the youth of the jets compared to the overall lifetime of a star, it is safe to say we are witnessing the ‘exact moment’ that the jets have just started to push through the surrounding gas,” explains Tafoya. “The jets carve through the surrounding material in as little as 60 years. A person could watch their progress throughout their lifetime.”

Over time those jets, thought to be caused by the interaction of the central star with a smaller secondary star that orbits it, will interact increasingly with the surrounding gas. The result will be a quite spectacular planetary nebula.

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Review of Kepler data uncovers seventeen more possible exoplanets

11:08 am

Worlds without end: In reviewing the entire Kepler database of 200,000 stars, scientists have found seventeen more candidate exoplanets, including one only 1.5 times the mass of the Earth that is also in the habitable zone.

From the paper’s abstract:

We present the results of an independent search of all ~200,000 stars observed over the four year Kepler mission (Q1–Q17) for multiplanet systems, using a three-transit minimum detection criterion to search orbital periods up to hundreds of days. We incorporate both automated and manual triage, and provide estimates of the completeness and reliability of our vetting pipeline. Our search returned 17 planet candidates (PCs) in addition to thousands of known Kepler Objects of Interest (KOIs), with a 98.8% recovery rate of already confirmed planets. We highlight the discovery of one candidate, KIC-7340288 b, that is both rocky (radius $\leqslant 1.6{R}_{\oplus }$) and in the Habitable Zone (insolation between 0.25 and 2.2 times the Earth’s insolation). Another candidate is an addition to the already known KOI-4509 system.

I must emphasize that these are candidate exoplanets, meaning their existence has not been confirmed by other observations, and could very well turn out to be false positives.

Still, that this independent review matched the previous list of Kepler candidates within 98.8% means that the list of exoplanet candidates from Kepler is solid and worth further study. With thousands of candidates, however, that further study is likely going to take a very long time. And the backlog will be growing significantly with the many thousands of additional exoplanet candidates expected to be found by TESS.

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First image of possible asteroid in orbit around the Earth

3:37 pm

asteroid orbiting the Earth?
Click for full image.

The Gemini telescope in Hawaii has produced the first image of what might be only the second asteroid ever discovered in orbit around the Earth.

The newly discovered orbiting object has been assigned the provisional designation 2020 CD3 by the International Astronomical Union’s Minor Planet Center. If it is natural in origin, such as an asteroid, then it is only the second known rocky satellite of the Earth ever discovered in space other than the Moon. The other body, discovered in 2006, has since been ejected out of Earth orbit. 2020 CD3 was discovered on the night of 15 February 2020 by Kacper Wierzchos and Teddy Pruyne at the Catalina Sky Survey operating out of the University of Arizona’s Lunar and Planetary Laboratory in Tucson, Arizona.

The photo to the right has been cropped to post here. The streaks are stars, since the telescope was tracking the asteroid in an attempt to cull the most resolution of it from the image.

This object is only a few yards across, and could very well be a piece of space junk from a mission launched many decades ago. It is also not in a stable orbit around the Earth, and is expected to be ejected from that orbit in April.

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Confirmed: Betelguese is brightening, as predicted

1:58 pm

More observations have now confirmed that Betelguese is once again brightening, as predicted.

Photometry secured over the last ~2 weeks shows that Betelgeuse has stopped its large decline of delta-V of ~1.0 mag relative to September 2019. The star reached a mean light minimum of = 1.614 +/- 0.008 mag during 07-13 February 2020. This is approximately 424+/-4 days after the last (shallower: V ~ +0.9 mag) light minimum was observed in mid-December 2018. Thus the present fading episode is consistent with the continuation of the persistent 420-430 day period present in prior photometry.

In other words, the star’s dimming, though deeper than earlier dips, was right in line with a well-known variation cycle. While absolutely worth close observation and study, the data now strongly suggests that this is relatively normal behavior for this aging red giant star. It will likely go supernova sometime in the future, not likely now.

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Astronomers photograph baby stars in Orion

9:17 am

Some of the baby stars surveyed
Click for full image.

Astronomers using two radio telescopes have created multi-wavelength radio images of 300 protoplanetary disks, or proplyds, found in the star forming region in the constellation Orion. The image to the right shows only a small sampling of the proplyds imaged.

“This survey revealed the average mass and size of these very young protoplanetary disks,” said John Tobin of the National Radio Astronomy Observatory (NRAO) in Charlottesville, Virginia, and leader of the survey team. “We can now compare them to older disks that have been studied intensively with [the radio telescope] ALMA as well.”

What Tobin and his team found, is that very young disks can be similar in size, but are on average much more massive than older disks. “When a star grows, it eats away more and more material from the disk. This means that younger disks have a lot more raw material from which planets could form. Possibly bigger planets already start to form around very young stars.”

Of the disks photographed, four appear to be extremely young, probably less than ten thousand years, because of their very blobby and irregular shape.

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Images reveal changes in Betelgeuse’s shape as it has been dimming

10:16 am

Betelgeuse dimmed
Click for full image.

Using the Very Large Telescope in Chile astronomers have produced before and after images of the red giant Betelgeuse, showing the changes to the star in the past year as it has dimmed by about 36%.

The image to the right, cropped and reduced to post here, was taken in December and shows the star in its dimmed state. Below the fold is a short video that compares this image with a photograph taken in January 2019. The star was then more spherical and evenly bright.

Betelgeuse’s misshaped profile and uneven brightness is not actually a new thing. See for example this 2017 image, where I noted that the bulge on the star’s side suggested “that continuous observations would reveal the outer atmosphere waxing and waning almost like the stuff inside a lava lamp.” The star is a giant gasbag that in the past has frequently been observed with dark patches on its surface and a sense that it is not always spherical. Those changes however have not occurred with such a significant dimming, a full magnitude

In late December I had posted a story noting that the dimming appeared to be expected, caused by the alignment of two different regular fluctuations of brightness, one 5.9 years long and the other 0.5 year long. It was expected that the star would begin brightening again.

Right now astronomers estimate that the low point in these cycles will occur on approximately February 21st. If the star begins to brighten following that date it would confirm that this dimming is just part of its cycles. If not, then it could be that we are in the preliminaries to a supernova event that would probably make Betelgeuse bright enough to be seen during the day.
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A baffling repeating fast radio burst

1:36 pm

Astronomers are baffled by a fast radio burst, a phenomenon that is a mystery in its own right, that also repeats its bursts in what appears to be a regular pattern.

Researchers looking at data from the Canadian Hydrogen Intensity Mapping Experiment Fast Radio Burst Project (CHIME/FRB) first spotted this FRB, known as FRB 180916.J0158+65, in 2019. In January 2020, they published a paper in the journal Nature that reanalyzed old data and found more than one burst from FRB 180916.J0158+65. They traced this FRB back to a relatively nearby spiral galaxy. What’s new in this latest paper, published Feb. 3 to the arXiv database, is the regular pattern in the bursts. The FRB, they found, goes through four-day cycles of regular activity, bleating out radio waves into space on an almost hourly basis. Then it goes into a 12-day period of silence. Sometimes the source seems to skip its usual four-day awake periods, or lets out only a single burst. CHIME/FRB is able to watch the FRB only some of the time, they noted, so it’s likely the detector misses many FRBs during the awake period.

At present they have no idea what is causing the pattern, other than a realization that it defies all the theories for explaining the previously discovered fast radio bursts.

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An update on Comet 2I/Borisov

8:23 am

Link here.

Overall, this second known interstellar object to pass through the solar system appears to be a very typical comet. They have found however that its nucleus is much smaller than at first thought, only 200 to 500 meters across, which means that radiation pressure from the Sun could cause its rotation to spin up, with the possibility that this spin could get fast enough to cause the comet to break up.

The comet made its closest approach to the Sun in December, and will spend the next year-plus flying outward to beyond Saturn.

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Successful first light for CHEOPS space telescope

12:02 pm

The science team for Europe’s exoplanet-hunting CHEOPS space telescope announced today that the telescope has successfully obtained its first pictures, and that all appears to be working correctly.

Preliminary analysis has shown that the images from CHEOPS are even better than expected. However, better for CHEOPS does not mean sharper as the telescope has been deliberately defocused. This is because spreading the light over many pixels ensures that the spacecraft’s jitter and the pixel-to-pixel variations are smoothed out, allowing for better photometric precision. “The good news is that the actual blurred images received are smoother and more symmetrical than what we expected from measurements performed in the laboratory,” says Benz. High precision is necessary for CHEOPS to observe small changes in the brightness of stars outside our solar system caused by the transit of an exoplanet in front of the star. Since these changes in brightness are proportional to the surface of the transit planet, CHEOPS will be able to measure the size of the planets. “These initial promising analyses are a great relief and also a boost for the team,” continues Benz.

I suspect the planned fuzziness of their images is why the press release did not include them.

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Two defunct satellites barely miss each other

9:42 pm

Missed it by that much: According to the US Space Command, two defunct satellites, one the first infrared space telescope ever launched and the other a military technology test satellite, apparently did not collide tonight, barely missing each other.

Prior to impact it was estimated they could get within as little as 40 feet. Since the military satellite had booms 60 feet long, the possibility of impact was quite real, especially because there was also a margin of error in the calculations and the two satellites were traveling almost 33,000 mph relative to each other. Had they hit each other the cloud of debris would have caused enormous problems, as the pieces would have been a threat to many other satellites presently in orbit.

Fortunately they missed each other. The problem of many such defunct satellites and upper stages and general space junk still exists however. Someone could make some good money providing a service to clean this stuff up. I suspect governments would be willing to pay to have it done.

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First images from Inouye Solar Telescope

3:36 pm

Close-up of the Sun by Inouye Telescope

Scientists have released the first images of the Sun taken by the new Daniel K. Inouye Solar Telescope on the island of Maui in Hawaii.

The image to the right, cropped to post here, is today’s released image, a close-up of the Sun’s surface granular structure, with each cell about the size of Texas.

Right now most of the telescope’s instruments are not yet on line. It is expected the telescope will become fully operational in July.

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GAO warns of more Webb delays

8:47 am

The race to the bottom between Webb and SLS continues! A new Government Accountability Office (GAO) report warns that there is high likelihood that NASA will not meet its March 2021 target launch date for the James Webb Space Telescope.

The report noted that the program performed an updated joint confidence level analysis of the mission’s cost in schedule in October. “Because of schedule delays resulting from technical challenges coupled with remaining risks faced by the project, the analysis assessed only a 12 percent confidence level for the project’s ability to meet the March 2021 launch readiness date,” the report stated.

NASA missions usually set cost and schedule estimates at the 70% confidence level. Using that metric, the launch would likely take place in July 2021, a delay of four months, according to the report.

Webb is now more than a decade behind schedule, with its budget ballooning from $1 billion to just under $10 billion. These facts essentially wiped out almost all new astronomical projects in the 2010s.

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Two abandoned satellites might collide

11:52 am

According to a company that monitors objects in low Earth orbit, two abandoned satellites might actually collide on January 29..

The two satellites, NASA’s IRAS space telescope and the experimental U.S. Naval Research Lab satellite GGSE-4, will swing past each other at 6:39 p.m. EST at an altitude of about 559 miles in the skies above Pittsburgh, Pennsylvania. They’ll be hurtling along their orbit at a relative velocity of about 32,880 miles per hour and could swing within 50 feet of each other.

LeoLabs noted that, at the time of the tweet, the odds of a collision were about 1 in 100 and said the relatively large size of the two spacecraft increased the risk of a collision.

IRAS was the first infrared space telescope ever launched, and operated for ten months after its launch in 1983. The other spacecraft was a National Security Agency test satellite of surveillance technology.

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Strange things at center of Milky Way

9:31 am

Astronomers have discovered an additional four more weird objects orbiting the supermassive black hole, dubbed Sagittarius A* (pronounced A-star) for a total of six, all of which display behavior that is inexplicable.

Part of a new class called G objects, they look compact most of the time and stretch out when their orbits bring them closest to the black hole. Those orbits range from about 100 to 1000 years. “These objects look like gas and behave like stars,” says Andrea Ghez, director of the Galactic Centre Group at the University of California, Los Angeles (UCLA) and co-author of a paper in the journal Nature.

The new discoveries are known simply as G3 to G6. G1 was discovered by Ghez’s research group back in 2005, and G2 by astronomers in Germany in 2012. “The fact that there are now several of these objects observed near the black hole means that they are, most likely, part of a common population,” says co-author Randy Campbell, from the Keck Observatory in Hawaii.

It is not surprising that the intense gravitational field of Sagittarius A* rips these objects into elongated stretched objects as their orbits bring them close to the black hole. What is very very puzzling is their apparent ability to spring back to compact form as their orbits take them away from the black hole.

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A second exoplanet orbiting Proxima Centauri?

9:32 am

Worlds without end: Astronomers think they have found evidence of a second exoplanet orbiting the nearest star, Proxima Centauri.

The planet, a super-Earth called Proxima Centauri c (Proxima c for short), has at least six times more mass than Earth and orbits its star every 5.2 years.

…“Stars like Proxima Centauri are rather restless and continuously present eruptions and spots on their surface, which make the detection of a planetary-induced oscillation very complicated,” says coauthor Fabio Del Sordo (University of Crete and Foundation for Research and Technology-Hellas in Heraklion, Greece). Because the observations span almost two decades, the scientists have confidently ruled out those sources of noise, but they caution that follow-up observations are needed to confirm that the signal comes from a planet.

There is a lot of uncertainty here, requiring an independent confirmation of this result. It would not be surprising if this exoplanet vanished when others took a look, finding it a creation not of a periodic gravitation wobble but of the random fluctuations of the star itself.

If it does exist, it will not likely be a place where life exists. Too far from this very dim red dwarf star to get enough energy. However, as a super-Earth it might someday in the far future be a great mining world.

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Spitzer SpaceTelescope shutdown in a week

9:20 am

After sixteen years in orbit, NASA will shut down the Spitzer Space Telescope on January 22, 2020,

The telescope is still functional in a somewhat limited manner but NASA wishes to save the annual budget of $14 million to operate it. Moreover, it will become redundant and significantly superseded once the infrared James Webb Space Telescope launches and becomes operational next year.

NASA had hoped a private organization would take over Spitzer’s operation, but apparently got no takers.

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