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Hubble Space Telescope lives: NASA fix gets backup hardware up and running – CNET

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The NASA/ESA Hubble Space Telescope during deployment in 1990.


NASA/Smithsonian Institution/Lockheed Corporation

NASA’s beloved Hubble Space Telescope has been facing one of its greatest challenges. A technical glitch left it in safe mode for over a month. This week, NASA said it finally tracked down the source of the issue and tried a new fix, and it seems to have worked.

“NASA has successfully switched to backup hardware on the Hubble Space Telescope, including powering on the backup payload computer, on July 15,” the space agency announced on Friday.

The telescope has been in service for over 30 years. The Hubble team had been looking at the payload computer — hardware dating back to the 1980s — as the potential source of a memory problem. “A series of multi-day tests, which included attempts to restart and reconfigure the computer and the backup computer, were not successful, but the information gathered from those activities has led the Hubble team to determine that the possible cause of the problem is in the Power Control Unit,” NASA said.  

As with the payload computer, the PCU is part of Hubble’s Science Instrument Command and Data Handling unit. The PCU is responsible for supplying a constant and steady source of electricity to the computer and its memory. Hubble is equipped with a lot of backup systems, including a spare PCU. 

Since the issue cropped up on June 13, Hubble’s science work has been stalled. The switch to backup hardware should give the telescope a new lease on life. “The Hubble team is now monitoring the hardware to ensure that everything is working properly,” said NASA. It will take over a day to get the science instruments out of safe mode before normal science operations can resume.  

NASA operates Hubble in partnership with the European Space Agency. “We’re extremely happy to announce that Hubble is back online!” ESA’s Hubble team tweeted on Friday. “Congratulations to the entire team that worked around the clock to make this happen.”

There has been concern for the aging telescope. Its successor, the much-delayed James Webb Space Telescope, is still here on Earth, waiting for a possible late-2021 launch.

Hubble has weathered many technical glitches in its time, and it’s looking like the venerable telescope will persevere through this latest one. Hold on, universe, Hubble is coming back.

Follow CNET’s 2021 Space Calendar to stay up to date with all the latest space news this year. You can even add it to your own Google Calendar.      

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Canadian Arctic fossils may be the oldest animal ever found, study suggests – CBC.ca

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Fossils that formed 890 million years ago in what is now the Northwest Territories may be by far the oldest evidence of animal life ever found, a controversial new Canadian study suggests.

The tiny fossils are “possible” remains of the skeleton of an ancient sponge, says a new study by Elizabeth Turner, professor of earth sciences at Laurentian University in Sudbury, Ont., published in Nature today.

A cautious news release from the journal titled “Potential Evidence for the Earliest Animal Life” said, “the findings, if verified, may represent the earliest known fossilized animal body and may pre-date the next-oldest undisputed sponge fossils by around 350 million years.” 

That would also make them more than 300 million years older than the oldest confirmed animal fossil until now, 574-million-year-old fossils from Mistaken Point, N.L. and Dickinsonia, an elliptical, leaf-like marine creature that grew up to 1.22 metres long and lived 558 million years ago.

The previous oldest confirmed sponge — widely considered to be the earliest group of animals — lived 535 million years ago.

This is the skeleton of a modern bath sponge or horny sponge from Greece seen under a microscope, which has a similar structure to the fossils. (Elizabeth Turner/Laurentian University)

Turner said she first found the fossils in pockets and crevices of ancient reefs called stromatolites built by photosynthetic microbes called cyanobacteria while studying the microbes themselves for her PhD in the 1990s. 

While the ancient reefs are in the Arctic now — more specifically, their fossilized remains are limestone deposits in the Mackenzie Mountains, which are located in the Northwest Territories near the Yukon border — 890 million years ago, they were much closer to the equator in the middle of a supercontinent called Rodinia, in a shallow inland sea. 

The fossils were worm-like and half the width of a human hair, branching and then rejoining. Turner was intrigued, as they were complex structures and she suspected they weren’t made by microbes. She puzzled over them for decades, returning periodically to gather more samples.

Then recently, Joachim Reitner in Germany, Robert Riding in the U.S. and Jeong-Hyun Lee in Korea, published research showing how similar fossils could be formed from horny sponges, the type of sponge used to make commercial bath sponges.

“They are truly identical to the ones that I had in my much older rocks,” Turner said. “There weren’t any other truly viable interpretations of the material.” 

Elizabeth Turner, a Laurentian University earth sciences professor, was the author of the new paper. In this photo, she does unrelated field work on northern Baffin Island in Nunavut. (C. Gilbert)

The reef pockets and crevices in the Mackenzie Mountains where the worm-like sponge fossils were found are similar to the environments where sponges live today, she said.

They were too dark for the cyanobacteria themselves to live in, so the microbes wouldn’t compete with the sponges for space and other resources. But it was close enough for a sponge to capture some of the oxygen produced by the microbes, which was in short supply at that time.

The microbes might also produce a source of food in the form of slime — something their modern relatives still do, giving them their nickname, “pond scum.” 

What other scientists think

In an unusual move, since peer review is usually anonymous, Nature disclosed that Reitner, Riding and Lee had all peer reviewed Turner’s article. Riding and Lee both confirmed they think Turner’s interpretation is correct.

Riding says it’s a “very interesting discovery.”

“The orderliness and neatness of this pattern, I think, is very distinctive,” he told CBC News in a phone interview, noting that the fossils are exceptionally well-preserved. “And if I found that pattern in younger rocks, I would say for sure that it was a sponge.”

He said that sponges have long been thought to be the earliest animal and were predicted to have evolved around the time that these fossils would have formed.

That said, Riding acknowledged that the simplicity of the fossils and their extraordinary age mean some other scientists might need more convincing.

He thinks more people will start to look for these types of fossils, and may start to check them for the biochemical fingerprints left behind by sponges, which have been found in younger fossils. That would convince the doubters, he said, but added that “in my opinion, it is a sponge fossil.”

This is one of the sites in the Mackenzie Mountains of the Northwest Territories. The mountains contain limestone from huge ancient reefs, which is where the fossils were found. (Elizabeth Turner/Laurentian University)

Some researchers skeptical

Other researchers contacted by CBC News were more skeptical.

Jonathan Antcliffe is a paleontologist at the University of Lausanne in Switzerland who has previously disputed other “oldest sponge” fossil discoveries.

He said fossils are usually identified by unique and distinctive characteristics for that group, and there are many for sponges, including hard skeletal elements called spicules that fossilize well. Those were not found in this fossil. 

While horny sponges don’t have spicules, Antcliffe said they’re one of the “weirdest” groups of modern sponges. He added that spicules should exist in even the earliest sponges, since they exist in a microbe that is thought to be the ancestor of sponges. 

Modern bath sponges or horny sponges don’t have hard skeletons, but are supported by networks of protein. The fossils are thought to be the remains of similar networks. (Svetlana Lukienko/Shutterstock)

Unlike Turner and Riding, he thinks the fossils could have been made by many different kinds of microbes. “These things could be absolutely anything,” he told CBC News. “There’s just nothing distinctive here at all.”

Qing Tang, a postdoctoral researcher at the University of Hong Kong, has previously written about the lack of really old sponge fossils being an “annoying problem for paleontologists,” given that they’re thought to have evolved much earlier than the oldest fossils, and most modern sponges (but not horny sponges) have hard skeletons that should be easily fossilized.

Some of his research has found that some very old sponges may not have had those hard skeletons.

But he said in this case, the fossils remind him of another fossil from between 635 million and 538 million years ago that was originally thought to be a sponge. After more detailed 3D analysis, researchers decided the fossils were more likely made by microbes.

He suggested more sophisticated 3D analysis are needed to confirm Turner’s discovery.

“This discovery is overall very interesting,” Qing said in an email.

“It will be a big step towards a better understanding of early animal evolution if the keratose sponge interpretation is eventually confirmed, particularly given its age… However, as is denoted in the title, these structures are best called possible sponge fossils due to relatively few characters preserved.”

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Hot and dry: SPIRou reveals the atmosphere of hot Jupiter Tau Boötis b – News | Institute for Research on Exoplanets

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Measuring the composition of the atmosphere of the hot Jupiter Tau Boötis b more precisely than ever, an iREx-led team of astronomers provides a better understanding of giant exoplanets.

Artistic rendition of the exoplanet Tau Boötis b and its host star, Tau Boötis. Credit : ESO/L. Calçada.

Using the SPIRou spectropolarimeter on the Canada-France-Hawaii Telescope in Hawaii, a team led by Stefan Pelletier, a PhD student at Université de Montréal’s Institute for Research on Exoplanets (iREx), studied the atmosphere of the gas giant exoplanet Tau Boötis b, a scorching hot world that takes a mere three days to orbit its host star. 

Their detailed analysis, presented in a paper published today in the Astronomical Journal, shows that the atmosphere of the gaseous planet contains carbon monoxide, as expected, but surprisingly no water, a molecule that was thought to be prevalent and should have been easily detectable with SPIRou. 

Tau Boötis b is a planet that is 6.24 times more massive than Jupiter and eight times closer to its parent star than Mercury is to the Sun. Located only 51 light-years from Earth and 40 per cent more massive than the Sun, its star, Tau Boötis, is one of the brightest known planet-bearing stars, and is visible to the naked eye in the Boötes constellation.

Tau Boötis b was one of the first exoplanets ever discovered, in 1996, thanks to the radial velocity method, which detects the slight back-and-forth motion of a star generated by the gravitational tug of its planet. Its atmosphere had been studied a handful of times before, but never with an instrument as powerful as SPIRou to reveal  its molecular content. 

Searching for water 

Assuming Tau Boötis b formed in a protoplanetary disk with a composition similar to that of our Solar System, models show that water vapour should be present in large quantities in its atmosphere. It should thus have been easy to detect with an instrument such as SPIRou.

“We expected a strong detection of water, with maybe a little carbon monoxide,” explained Pelletier. “We were, however, surprised to find the opposite: carbon monoxide, but no water.”

The team worked hard to make sure the results could not be attributed to problems with the instrument or the analysis of the data.

“Once we convinced ourselves the content of water was indeed much lower than expected on Tau Boötis b, we were able to start searching for formation mechanisms that could explain this,” said Pelletier.

Studying hot Jupiters to better understand Jupiter and Saturn

“Hot Jupiters like Tau Boötis b offer an unprecedented opportunity to probe giant planet formation”, said co-author Björn Benneke, an astrophysics professor and  Pelletier’s PhD supervisor at UdeM. “The composition of the planet gives clues as to where and how this giant planet formed.”

The key to revealing the formation location and mechanism of giant planets is imprinted in their molecular atmospheric composition. The extreme temperature of hot Jupiters allows most molecules in their atmospheres to be in gaseous form, and therefore detectable with current instruments. Astronomers can thus precisely measure the content of their atmospheres.

“In our Solar System, Jupiter and Saturn are really cold,” said Benneke. “Some molecules such as water are frozen and hidden deep in their atmospheres; thus, we have a very poor knowledge of their abundance. Studying hot Jupiters provides a way to better understand our own giant planets. The low amount of water on Tau Boötis b could mean that our own Jupiter is also drier than we had previously thought.” 



SPIRou: a unique instrument

Tau Boötis b is one of the first planets studied with the new SPIRou instrument since it was recently put into service at the Canada-France-Hawaii Telescope. This instrument was developed by researchers from several scientific institutions including UdeM.

“This spectropolarimeter can analyze the planet’s thermal light — the light emitted by the planet itself — in an unprecedentedly large range of colours, and with a resolution that allows for the identification of many molecules at once: water, carbon monoxide, methane, etc.” said co-author and iREx researcher Neil Cook, an expert on the SPIRou instrument. 

The team spent 20 hours observing the exoplanet with SPIRou between April 2019 and June 2020.

“We measured the abundance of all major molecules that contain either carbon or oxygen,” said Pelletier. “Since they are the two most abundant elements in the universe, after hydrogen and helium, that gives us a very complete picture of the content of the atmosphere.” 

Like most planets, Tau Boötis b does not pass in front of its star as it orbits around it, from Earth’s point of view. However, the study of exoplanet atmospheres has mostly been limited to “transiting” planets – those that cause periodic dips in the light of their star when they obscure part of their light.

“It is the first time that we get such precise measurements on the atmospheric composition of a non-transiting exoplanet,” said PhD student Caroline Piaulet, a co-author of the study.

“This work opens the door to studying in detail the atmospheres of a large number of exoplanets, even those that do not transit their star.” 

A composition similar to Jupiter

Through their analysis, Pelletier and his colleagues were able to conclude that Tau Boötis b’s atmospheric composition has roughly five times as much carbon as that found in the Sun, quantities similar to that measured for Jupiter. 

This may be a suggest that hot Jupiters could form much further from their host star, at distances that are similar to the giant planets in our Solar System, and have simply experienced a different evolution, which included a migration towards the star. 

“According to what we found for Tau Boötis b, it would seem that, at least composition-wise, hot Jupiters may not be so different from our own Solar System giant planets after all,” concluded Pelletier.

About this study 

Where is the water? Jupiter-like C/H ratio but strong H2O depletion found on Tau Boötis b using SPIRou,” by Stefan Pelletier et al., was published July 28th, 2021 in the Astronomical Journal. 

In addition to Stefan Pelletier, Björn Benneke, Neil Cook and Caroline Piaulet, the team includes Institute for research on exoplanets (iREx) members Antoine Darveau-Bernier, Anne Boucher, Louis-Philippe Coulombe, Étienne Artigau, David Lafrenière, Simon Delisle, Romain Allart, René Doyon, Charles Cadieux and Thomas Vandal, all based at Université de Montréal, and seven other co-authors from France, the United States, Portugal and Brazil. 

Funding was provided by the the Technologies for Exo-Planetary Science (TEPS) CREATE program, the Fonds de recherche du Québec – Nature et technologies (FRQNT), the Natural Sciences and Engineering Research Council of Canada (NSERC), the Trottier Family Foundation and the French National Research Agency (ANR).

Media Contacts 

Marie-Eve Naud
EPO Coordinator, Institute for Research on Exoplanets
Université de Montréal, Montréal, Canada
514-279-3222, marie-eve.naud@umontreal.ca

Scientific Contacts 

Stefan Pelletier (lead author)
Ph.D. Candidate, Institute for Research on Exoplanets
Université de Montréal, Montréal, Canada
stefan.pelletier@umontreal.ca  

Björn Benneke (co-author)
Professor, Institute for Research on Exoplanets
Université de Montréal, Montréal, Canada
514-578-2716, bjorn.benneke@umontreal.ca  

Additional links 

Scientific article (Astronomical Journal, open source version on arXiv.org)
Université de Montréal press release
Canada-France-Hawaii press release

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Scientists capture most-detailed radio image of Andromeda galaxy to date – UBC News

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‘Disk of galaxy’ identified as region where new stars are born

Scientists have published a new, detailed radio image of the Andromeda galaxy – the Milky Way’s sister galaxy – which will allow them to identify and study the regions of Andromeda where new stars are born.

Sofia Fatigoni

The study – which is the first to create a radio image of Andromeda at the microwave frequency of 6.6 GHz – was led by University of British Columbia physicist Sofia Fatigoni, with colleagues at Sapienza University of Rome and the Italian National Institute of Astrophysics. It was published online in Astronomy and Astrophysics.

“This image will allow us to study the structure of Andromeda and its content in more detail than has ever been possible,” said Fatigoni, a PhD student in the department of physics and astronomy at UBC. “Understanding the nature of physical processes that take place inside Andromeda allows us to understand what happens in our own galaxy more clearly – as if we were looking at ourselves from the outside.”

Prior to this study, no maps capturing such a large region of the sky around the Andromeda Galaxy had ever been made in the microwave band frequencies between one GHz to 22 GHz. In this range, the galaxy’s emission is very faint, making it hard to see its structure. However, it is only in this frequency range that particular features are visible, so having a map at this particular frequency is crucial to understanding which physical processes are happening inside Andromeda.

In order to observe Andromeda at this frequency, the researchers required a single-dish radio telescope with a large effective area. For the study, the scientists turned to the Sardinia Radio Telescope, a 64-metre fully steerable telescope capable of operating at high radio frequencies, located in Italy.

The Sardinia Radio Telescope, located in Sardinia, Italy. Credit: S. Fatigoni et al (2021)

The Sardinia Radio Telescope, located in Sardinia, Italy. Credit: S. Fatigoni et al (2021)

It took 66 hours of observation and consistent data analysis for the researchers to map the galaxy with high sensitivity.

They were then able to estimate the rate of star formation within Andromeda, and produce a detailed map that highlighted the ‘disk of the galaxy,’ as the region where new stars are born.

“By combining this new image with those previously acquired, we have made significant steps forward in clarifying the nature of Andromeda’s microwave emissions and allowing us to distinguish physical processes that occur in different regions of the galaxy,” said Dr. Elia Battistelli, a professor in the department of physics at Sapienza and coordinator of the study.

“In particular, we were able to determine the fraction of emissions due to thermal processes related to the early stations of new star formation, and the fraction of radio signals attributable to non-thermal mechanisms due to cosmic rays that spiral in the magnetic field present in the interstellar medium,” Fatigoni said.

Final image of the Andromeda galaxy after averaging over the whole bandwidth at 6.6 GHz. Credit: S. Fatigoni et al (2021)

Final image of the Andromeda galaxy after averaging over the whole bandwidth at 6.6 GHz. Credit: S. Fatigoni et al (2021)

For the study, the team also developed and implemented software that allowed them to test new algorithms to identify never-before-examined lower emission sources in the field of view around Andromeda at a frequency of 6.6 GHz.

From the resulting map, researchers were able to identify a catalog of about 100 ‘point sources’ including stars, galaxies and other objects in the background of Andromeda.

Interview language(s): English, Italian

Note for reporters: Sofia Fatigoni is based in Rome, Italy and is available for interviews until 3 p.m. PST.

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