Category Archives: Astronomy

Using NASAs Chandra X-ray Observatory and ESAs XMM-Newton satellite, astronomers have investigated unusual X-ray activity in three white dwarfs: KPD 0005+5106, PG 1159-035 and WD 0121-756.

This artists illustration depicts what Chu et al. think is happening in the binary system KPD 0005+5106. The data suggest the white dwarf (blue sphere) is blasting a companion object (brown and red object on right), which is either a low-mass star or planet, with waves of heat and radiation. The white dwarf is also pulling material from the companion into a disk around itself, which the artist shows in orange, before it slams into its north and south poles. This process is contributing to the destruction of the companion through powerful gravitational forces. Image credit: NASA / CXC / M. Weiss / ASIAA / Chu et al.

Most stars, including the Sun, will become white dwarfs after they begin to run out of fuel, expand and cool into a red giant, and then lose their outer layers. This evolution leaves behind a stellar nub that slowly fades for billions of years.

Typically, white dwarfs give off low-energy X-rays. However, KPD 0005+5106, PG 1159-035 and WD 0121-756 also had surprisingly bright X-ray emission at higher energies.

KPD 0005+5106 stood out among this group. It had high-energy X-ray emission that was regularly increasing and decreasing in brightness every 4.7 hours.

This recurring ebb and flow of X-rays indicates that KPD 0005+5106 has an object in orbit around it either a very low-mass star or a Jupiter-like planet.

Material from the low-mass star or planet could be slamming into the north and south poles of the white dwarf, creating a bright spot of high-energy X-ray emission.

As the white dwarf and its companion orbit around each other this hot spot would go in and out of view, causing the high-energy X-rays to regularly increase and decrease.

We didnt know this white dwarf had a companion before we saw the X-ray data, said Dr. You-Hua Chu, an astronomer in the Institute of Astronomy and Astrophysics at Academia Sinica.

Weve looked for the companion with optical light telescopes but havent seen anything, which means it is a very dim star, a brown dwarf, or a planet.

KPD 0005+5106 is located about 1,300 light-years in the constellation of Cassiopeia.

It is one of the hottest known white dwarf stars, with a surface temperature of about 200,000 K.

The companion object is almost 805,000 km (500,000 miles) away from the white dwarf, only about one thirtieth of the distance from Mercury to the Sun. Whatever this object is, its getting blasted with heat, said Dr. Jess Toala, an astronomer at the National Autonomous University of Mexico.

The astronomers looked at what would happen if this object was a Jupiter-mass planet a possibility that agrees with the data more readily than a dim star or a brown dwarf.

In their models, the white dwarf would pull material from the planet onto the white dwarf, a process that the planet could only survive for a few hundred million years before eventually being destroyed.

This stolen material swirls around the white dwarf, which glows in X-rays that Chandra can detect.

This is a slow demise for this object thats basically being ripped apart by constant gravitational forces. It would be a very unpleasant place to be, said Dr. Martn A. Guerrero, an astronomer at the Institute of Astrophysics of Andalusia.

The two other white dwarfs PG 1159-035 and WD 0121-756 were also thought to be solitary objects, but they show similar energetic X-ray emission to KPD 0005+5106. By analogy, this suggests they may also have faint companions, possibly planets.

The hard X-ray emission from apparently single white dwarfs is powered by accretion from sub-stellar companions or giant planets, and is modulated by the orbital motion with a period of 4.7 hr, the authors concluded.

The results appear in the Astrophysical Journal.

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You-Hua Chu et al. 2021. Hard X-Ray Emission Associated with White Dwarfs. IV. Signs of Accretion from Substellar Companions. ApJ 910, 119; doi: 10.3847/1538-4357/abe5a5

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Hard X-Ray Emission from White Dwarfs Reveals Their Hidden Companions - Sci-News.com

An expert in astronomy has given his top tip of what to do if an asteroid is found to be heading towards Earth.

Professor Alan Duffy, director of the Space Technology and Industry Institute Professor has said that if a giant boulder of space rock is hurtling our way, "don't look at it".

Duffy gave the obvious-sounding advice to the I've Got News For You podcast.

He said: "I would say the best advice is, for goodness sake, do not look at this thing.

"I mean, its going to be hard not to the brightness of the glare from these objects burning up in the atmosphere.

"Thats actually what caused a lot of the injuries in Chelyabinsk (a meteor strike in Russia in 2013), people not unreasonably looked up at this enormous burning fireball in the sky, whose brightness was essentially that of the Sun by the time it finally erupted, that caused a lot of retina damage so make sure youre not looking right at it."

The light caused by the Chelyabinsk strike was brighter than the sun and was visible up to around 100km away from the area.

This "don't look" warning comes a few days after NASA fired a rocket at an asteroid in an attempt to find out whether it's possible to force such a large object hurtling through space to change course in an attempt to form some sort of plan to protect Earth.

The Double Asteroid Redirection Test (DART) mission launched from a SpaceX explosive-packed rocket yesterday, with the missile expected to hit Dimorphos in September 2022.

Professor Duffy, however, did say that an asteroid impacting upon earth is "definitely not our biggest problem," and that Dimorphos, which is around 160 metres across, is known only as a "city killer".

He added: "Those things are going to hit the earth about once every 1000 or 2000 years, so its not a super rare event by geological standards but is maybe not something were going to be worrying about tomorrow."

To stay up to date with all the latest breaking news, just in case an asteroid is found to be hurtling towards us, make sure you sign up to one of our newsletters here.

Continued here:

Astronomer explains one thing you should avoid if an asteroid is hurtling towards Earth - Daily Star

SHANGHAI When the telescope at eastern Chinas Purple Mountain observatory captured a snippet of a hitherto unknown asteroid in 1978, the astronomers named it after Ye Shuhua in honor of her contributions to Chinas modern astronomy advancements.

Her career in astronomy began in 1951, when Ye, then in her early 20s, joined the Shanghai Astronomy Observatory. It was just two years after the founding of the Peoples Republic of China, and Ye had just succeeded with a small revolution of her own by becoming the institutes first female researcher.

During her first decade at the observatory, she worked on measuring time using the positions of stars relative to Earth. In the early 70s, the government decided to move Chinas time service to the Shaanxi observatory in central China for its better broadcast reach and better protection from a potential enemy invasion. Ye had to brainstorm what the Shanghai observatory should work on next.

Thats when she decided to build Chinas very-long-baseline interferometry (VLBI), a network of telescopes that work together to track celestial objects and spacecraft. Because a VLBI performs best when the telescopes are far apart, Ye was determined to build three: one on the eastern coast in Shanghai, one in northwestern Chinas Xinjiang region, and one in Yunnan, in the countrys southwest.

There were enormous challenges to overcome, both technologically and financially. At the time, the most technologically advanced countries had just begun experimenting with VLBI networks. Yes proposal met strong headwinds. But she didnt budge.

Now, decades later, the four-telescope-strong network an additional one was built in Beijing is foundational to Chinas ambitious space exploration program.

Ye became the head of Shanghai Astronomical Observatory in 1993, becoming the first female leader at a Chinese observatory and there havent been many since. She was also the vice-president of the International Astronomical Union, a non-government organization of astronomers, between 1988 and 1994.

Earlier this month, while Ye Shuhua, the 17-kilometer-wide space rock, was hurtling along its orbit around the sun somewhere between Mars and Jupiter, Ye Shuhua, the considerably smaller human, gave a speech at the 4th World Laureates Forum in Shanghai.

If you want to get something, you have to fight for it, Ye, standing on the podium in a crimson red coat, told the audience in fluent English.

Speaking with Sixth Tone during the forum, Ye discussed her work at the Shanghai Astronomy Observatory, womens role in astronomy, and the outlook of the Chinese space program. The interview has been edited for brevity and clarity.

Visitors stand in front of a digital recreation of the sun at the newly opened Shanghai Planetarium, July 30, 2021. Hector Retamal/AFP

Sixth Tone: Youve devoted your life to astronomy. What attracted you to this field?

Ye Shuhua: I like it because astronomy doesnt involve competing with people or with the world the universe is the only thing in your eyes. The most important thing we do is to help people understand the secrets of the universe better. Besides, astronomy actually has many practical applications, such as our Beidou satellite navigation system and time measurement.

Sixth Tone: Having witnessed the evolution of Chinese astronomy for 70 years, which developments instilled you with the most optimism?

Ye: I think now, like the last 10 years or so, is the best era for astronomy in China. There is a lot of big equipment being built. Look at FAST, our 500-meter telescope, which is the envy of international peers. I'm not saying it's the greatest thing in the world, but it's very distinctive.

The first giant radio telescope was built in the United States (territory Puerto Rico), but at that time, some 50 years ago, there were still many technical challenges even the U.S. couldnt overcome. With technology advancements in recent years, Nan Rendong, whos a really good friend of mine, decided to lead the project of building a giant telescope in China. He and his team put in a lot of effort to improve the design of FAST and made it really efficient.

Sixth Tone: Have you been to FAST? What was your impression?

Ye: Yes I have been there. I just think its too spectacular so it has attracted too much of an audience. People from China and abroad come to check it out. Of course we welcome them, but the more people, the larger the impact on observation work. For astronomical observations, we dont want to have a lot of people around.

But as time passes, maybe people will gradually get tired of it and lose interest, and not so many people will come.

Sixth Tone: Was building Chinas VLBI network a difficult process?

Ye: When the Peoples Republic was just founded, the country still faced all kinds of difficulties. At that time, time keeping and broadcasting were the most urgent tasks. So my colleagues and I put a lot of effort into it. But later, the government realized that placing time work in Shanghai would be dangerous if a war ever broke out on the eastern coast of the country, the time service could be easily knocked out. Also, its difficult to broadcast time to the western part of China, so they decided to move the time service to the central province of Shaanxi.

But in this way, the Shanghai station lost what it does for a living. So we had to find something else. I looked around and thought the most promising work is VLBI. At that time, this technology just appeared in the U.S., and even in the U.S. the project was struggling to gain approval because its expensive and difficult. But I was very ambitious and not afraid of anything at the time, and I was convinced that it was the best thing to work on.

I proposed that we should build three stations in China, but there was only enough money for two stations. Building the Shanghai and Yunnan stations was the easy option, but I decided to work on the hardest, which is the one in Urumqi, in Xinjiang. At the time the city had a tiny observatory with very few staff and barely any equipment.

But I thought that if I didnt insist on setting up the Urumqi station, no one would care about this observatory and no one would want to put in the hard work. VLBI works better when the stations are far apart, so I was very stouthearted. People say do the easy task first and then work on the difficult. But I did the reverse. If you dont seize the opportunity, it may be gone forever.

With VLBI, my colleagues at the Shanghai observatory help determine what to do when a spacecraft needs to change orbit in space. The calculations are very accurate and impressively fast. Im very proud.

A display shows a mockup of the Earth at the Shanghai Planetarium, July 30, 2021. Hector Retamal/AFP

Sixth Tone: Shanghai has recently built the worlds largest planetarium. Have you been there?

Ye: I have. I think this planetarium is certainly very beautiful. But there is still a lot of room for improvement.

I hope that the planetarium can be more accessible and enjoyable to all kinds of people, so that even senior citizens can visit and learn about the universe. Many elderly peoples views are constrained by religiosity, so if they can understand the universe, maybe it will help them a little. If the planetarium is full of very sophisticated stuff, the general public might not learn much during a visit. What I hope for is a planetarium that serves the whole society.

Sixth Tone: What is one of the unsolved mysteries of the universe that you would like to know the most?

Ye: Ah there are so many. Black holes, for example. Everyone wants to know more, right? But personally I think projects that are directly related to practical use are the foremost important thing that we have to do well. For example, we want to go explore the moon. But if we dont devote efforts in the VLBI, we cant guarantee a successful landing every time.

Sixth Tone: In the last decade or so, China has built many sophisticated and large instruments, like FAST. But is the progress of Chinas theoretical astronomy developing as fast as the hardware?

Ye: Previously, there was a significant lack of resources in astronomy. And because for practical fields like telescopes and satellite navigation, we have to make sure the data are 100% correct, we allocated a lot of humanpower. But it does not mean that no attention was paid to theoretical astronomy research. For example, our current head of the Shanghai Observatory is very much into black hole research. Now that the number of people in astronomy is increasing, and astronomical research is getting more support, there will be a more balanced development in the future. I even expect China to lean toward theoretical astronomy research.

Ye Shuhua gives a speech at an opening ceremony for the Shanghai Science & Technology Museums astronomical research center, Shanghai, Dec. 18, 2020. Wang Rongjiang/People Visual

Sixth Tone: Youre the first female director at any Chinese observatory, and there are still very few females in leadership roles in Chinas astronomy field. Did you have to break the glass ceiling?

Ye: After I graduated from university, I came back to the Chinese mainland after working as a teacher for two years in Hong Kong. I went to the Purple Mountain Observatory to look for a job, and they told me they only had a vacancy for a man. I was stunned when I heard that. That was in 1951. So I wrote a letter to the director of the Observatory, where I listed five reasons why he was wrong to not hire me.

When I was young, I wasnt afraid of anything. And the letter did get me a job at the Shanghai station.

Sixth Tone: Astronomy is still heavily dominated by males. How can we encourage more women into the field?

Ye: In astronomy, there are now more and more female scientists. But the proportion is still small. Women are still burdened with more duties than men in and outside the family, like caring for children and the elderly. This situation is not unique to China women around the world face it.

I feel a bit guilty about my own family, because I spent most of my time at work and had to constantly go on business trips. But its the nature of my job, so theres nothing more to say. I hope that, in the future, if there are better arrangements for childcare and family responsibilities, women will definitely get a better working environment. Im afraid its not so easy to change it can only be done gradually.

Contributions: Xu Jialu; editor: Kevin Schoenmakers.

(Header image: Ye Shuhua is pictured during the 4th World Laureates Forum in Shanghai, Nov. 1, 2021. People Visual)

Continued here:

Through the Glass Ceiling, and Beyond - Sixth Tone

A smattering of asteroids between Mars and Jupiter have been named after Ottawa-area astronomers.

On Nov. 8, the International Astronomical Union's naming working group for small bodies released the new names of 40 asteroids something it does about once a month.

In this bunch Ottawa-area astronomer Roger Hill recognized all the names, including his own. A handful of asteroids were named after amateur Ontario astronomers who'd worked with the Royal Astronomical Society of Canada.

Those included Kim Hay,president of the Kingston, Ont., centre of the society, Hill, who was on the board of the Hamilton, Ont., centre for decades, and Brian McCullough whoseasteroid was named in October's list volunteered with the Ottawa centre.

Hill was nominated more than three years ago by his fellow astronomers in Hamilton for his work on the board, editing the society's newsletter and in public outreach.

"I'd check maybe once a year just to see if my name had been added to the list. But alas, I was not immediately after Roger Federer, who has one as well. So, I gave up looking," he said.

That changed last week and Hill said he was "over the moon about it."

"This is a lifelong dream to have a piece of the solar system named after me. It's not something I ever expected and I'm incredibly grateful," he said. "It's really nice to be recognized, particularly by one's peers."

Hill got his first telescope when he was 10 years old. Kids, he says, are fascinated by the big numbers of space and he felt compelled to share the feeling that staring at the stars can put "body and soul back together again."

All in a Day9:12Asteroid named after Kanata astronomy educator

When Hill negotiated where to move during retirement, his only request to his wife: dark skies. The two settled in Cardinal, Ont., about an hour south of Ottawa.

From this location, he expects it will be about six months before his asteroid is hopefully visible.

The asteroid is six kilometres in diameter and takes just over four years to orbit the sun. It's 300,000 times fainter than the eye can see, so not particularly bright.

Even with his observatory and a telescope with a mirror 30 centimetres in diameter, he doesn't think he'll be able to see it, but he's hoping a long exposure picture taken with the aid of the telescope will be able to capture it.

Unlike Hill, McCullough wasn't aware the Ottawa centre had nominated him and hearing about the asteroid called (10059) McCullough = 1988 FS2was a complete surprise.

He first became enamoured with astronomy as a navigator with the Royal Canadian Navy in the 1970s.

"I was so thrilled and so enthusiastic to learn more all the time. I couldn't contain myself and I had to share it with others," he said.

He's spent many years bringing out his telescope for community groups and Girl Guides and looksforward to returning to it oncepandemic measures allow.

McCullough says the recognition for his service makes him emotional, even more important than having his name "hanging on an asteroid."

His daughter is an astrophysicist and was able to look up the particulars of his asteroid. He told CBC Radio's All In A Day she was able to find out the asteroid was one of four picked at random from 1,700 possibilities.

"The reason they chose this one is because it doesn't vary in its brightness, very much, so they can use it kind of like a standard hanging in the asteroid belt to compare comets against," McCullough said.

It's very dim, according to McCullough, only reflecting 20 per cent of the sunlight that hits it, comparable to Pluto, which he says he's been able to see with his telescope.

"This would be right on the edge of observation/imagination [with a backyard instrument], you could just barely see it."

His asteroid is one of just under 23,000 that have been named in the asteroid belt, of which there are more than a million with a diameter of more than one kilometre.

Go here to read the rest:

'Over the moon': Eastern Ontario astronomers recognized with asteroid names - CBC.ca

The IDL Astronomy Users Library is a central repository for low-level astronomy software written in the commercial language IDL. The Library is not meant to be an integrated package, but rather is a collection of procedures from which users can pick and choose (and possibly modify) for their own use. Submitted procedures are given a cursory testing, but are basically stored in the Library as submitted. Instrument-specific software is generally not included in the IDL Astronomy Library, but can be found at the Links to Other Astronomy and IDL related sites.

The entire contents of the Library can be downloaded in a tar file or in a .zip file from the the download site . Additional software, not included in the tar files, is available in a contrib directory. Individual procedures can be copied by browsing through a list of one-line descriptions. Changes to the contents of the Library are recorded in a news file. A versioned copy of the library isavailable on GitHub, and one can also be download the Library with the command git clone git://github.com/wlandsman/IDLAstro.git

Some routines in the IDL Astronomy Library make use of programs in theCoyote Graphics Library, which must be downloaded separately. Alternatively, one can download coyote_astron.tar.gz which contains a subset of the Coyote procedures needed for the Astronomy library. We also suggest downloading the MPFIT curvefitting routines developed by Craig Markwardt, although it is currently onlyused by one Astronomy Library routine (SOLVE_ASTRO ) .

Documentation is available describing the various options for working with FITS data in IDL.

The IDL Astronomy Library requires at least IDL V6.4. However, separate (frozen) versions of the Library that work with earlier versions of IDL are available at the /old download site.

The success of the IDL Astronomy User's Library depends on the willingness of users to give as well as take. Please inform Wayne Landsman of any possible contributions to the Library, programming bugs or documentation errors, or of relevant web sites.

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The IDL Astronomy User's Library

Astronomers detected the temporary dimming of X-rays from a system where a massive star is in orbit around a neutron star or black hole (shown in the artists illustration). This dimming is interpreted as being a planet that passed in front of an X-ray source around the neutron star or black hole. Credit: NASA/CXC/M. Weiss

Using ESAs XMM-Newton and NASAs Chandra X-ray space telescopes, astronomers have made an important step in the quest to find a planet outside of the Milky Way.

Spotting a planet in another galaxy is hard, and even though astronomers know that they should exist, no planetary systems outside of the Milky Way have been confirmed so far. Because the light from another galaxy is packed into a tiny area on the sky, it is very difficult for telescopes to distinguish one star from another, let alone a planet orbiting around them. And the usual techniques to find exoplanets in our galaxy dont work as well for planets outside of it.

This image shows the Whirlpool Galaxy (M51) as seen at X-ray wavelengths by ESAs XMM-Newton X-ray Observatory. Credit: ESA

This is different when studying X-rays, instead of visible light, in a galaxy. Because there are less objects that shine bright in X-ray light, an X-ray telescope like ESAs XMM can more easily distinguish between objects when observing a galaxy. Those objects are therefore easier to identify and study, and it might be possible to find a planet around them.

Some of the brightest objects that can be studied in external galaxies are the so-called X-ray binaries. They consist of a very compact object a neutron star or black hole that is eating material from a companion, or donor, star orbiting around it. The infalling material is accelerated by the intense gravitational field of the neutron star or black hole and heated to millions of degrees, producing a lot of bright X-rays. Astronomers expect that theoretically, planets passing in front of (transiting) such a source would block these X-rays, causing a dip in the observed X-ray light curve.

X-ray binaries may be ideal places to search for planets, because, although they are a million times brighter than our Sun, the X-rays come from a very small region. In fact, the source that we studied is smaller than Jupiter, so a transiting planet could completely block the light from the X-ray binary, explains Rosanne Di Stefano from the Center for Astrophysics, Harvard & Smithsonian in the United States, and first author of a new study published in Nature Astronomy today.

A composite image of M51 with X-rays from Chandra and optical light from NASAs Hubble Space Telescope contains a box that marks the location of the possible planet candidate. Credit: X-ray: NASA/CXC/SAO/R. DiStefano, et al.; Optical: NASA/ESA/STScI/Grendler

Rosanne and colleagues searched in Chandra and XMM-Newton data of three galaxies for such X-ray transits, dips in the light that could be explained by planets. And they found a very special signal in the Whirlpool Galaxy (M51) that they decided to study in more detail. The dip occurred in X-ray binary M51-ULS-1 and completely blocked the signal for a few hours, before it came back again.

Now the game of carefully crossing off possible explanations began, before the researchers could even consider the option of an extragalactic planet. We first had to make sure that the signal was not caused by anything else, says Rosanne, whose team argues against a number of possibilities in their new publication. We did this by an in-depth analysis of the X-ray dip in the Chandra data, analyzing other dips and signals in the XMM data, and also modeling dips caused by other possible events, including a planet.

Infographic: A planet in another galaxy. Credit: ESA

Could the X-ray dip be caused by small stars like a brown or red dwarf? No, they argue, the system is too young for that, and the transiting object too large.

Could it be a cloud of gas and dust? Not likely, the team says, because the dip indicates a transiting object with a well-defined surface, which would not be the same for a passing cloud. Even if the planet had an atmosphere, it would still have a more well-defined surface than a cloud.

Could the dip be explained by variations in brightness of the source itself? The paper authors are confident that this is not the case, because although the light from the source completely disappeared for a few hours before it came back, the temperature and light colors stayed the same.

Lastly, the team also compared the dip to another blockage of the light caused by the donor star passing in front of the compact star. This was partly observed by XMM-Newton and caused a much longer black-out, which was different from the dip caused by a possible planet.

We did computer simulations to see whether the dip has the characteristics of a planet transiting, and we find that it fits perfectly. We are pretty confident that this is not anything else and that we have found our first planet candidate outside of the Milky Way, adds Rosanne.

The team also speculates about the characteristics of the planet based on their observations: it would be the size of Saturn, orbiting the binary star system from tens of times the Earth-Sun distance. It would make one full orbit roughly every 70 years, and be bombarded with extreme amounts of radiation, making it uninhabitable by life as we know it on Earth.

This long orbit of the planet candidate is also a limitation for the study, because the event cant be repeated any time soon. Thats why the team remains careful to say that they found a possible planet candidate, for which the broader community might find other explanations, although they have not been found after careful research by the team. We can only say with confidence that it doesnt fit any of our other explanations, Rosanne clarifies.

Still, this is an exciting step forward in the quest to find a planet outside of the Milky Way. This is the first planet candidate that would orbit a known host system, as compared to candidates found with gravitational lenses. This would also be the first time that a planet is found orbiting an X-ray binary. The existence of those planets is consistent with the fact that planets are found around pulsars (rapidly rotating neutron stars), and some of these pulsars have been part of an X-ray binary in the past.

The first confirmed planet outside of our Solar System was found around a pulsar, an object typically observed in X-rays. I am excited that X-rays now also play important step in the search for planets beyond the border of our galaxy, says Norbert Schartel, XMM-Newton Project Scientist for ESA.

Now that we have this new method for finding possible planet candidates in other galaxies, our hope is that by looking at all the available X-ray data in the archives, we find many more of those. In the future we might even be able to confirm their existence, says Rosanne.

For more on this discovery:

Reference: A possible planet candidate in an external galaxy detected through X-ray transit by Rosanne Di Stefano, Julia Berndtsson, Ryan Urquhart, Roberto Soria, Vinay L. Kashyap, Theron W. Carmichael and Nia Imara, 25 October 2021, Nature Astronomy.DOI: 10.1038/s41550-021-01495-wPDF

See the article here:

Astronomers May Have Discovered a Planet in Another Galaxy - SciTechDaily

Planetary scientist Jim Bell, Ph.D., is scheduled to deliver an illustrated, nontechnical presentation, Postcards from Mars: The Latest from the International Armada of Robot Explorers, 7 p.m. today via livestream on YouTube.

The virtual event is part of the Silicon Valley Astronomy Lecture Series through Foothill College, now in its 22nd year.

Ten missions have successfully landed on Mars since 1976, including six rovers that have traversed across a total of nearly 30 miles of terrain on the Red Planet. Bell has been the lead or deputy scientist in charge of the science cameras on the NASA Spirit, Opportunity, Curiosity and Perseverance rovers, with a front-row seat for their photographic and geologic adventures.

In his presentation, Bell will share his favorite images and stories from inside mission operations and describe the major scientific findings made by the roving and landed missions over the past 45 years, focusing especially on the latest results streaming in from the still-active Curiosity and Perseverance rovers. He also will discuss plans for the next Martian rover.

Bell is a professor in the School of Earth & Space Exploration at Arizona State University and an astronomer who has been involved in solar system exploration using data from the Hubble Space Telescope, Mars rovers, Voyager 2 and orbiters sent to Mars, the Moon and several asteroids. His research focuses on the use of remote sensing imaging and spectroscopy to assess the geology, composition and mineralogy of the surfaces of planets, moons, asteroids and comets.

Bell is also the author of many science books related to space exploration, including Postcards from Mars, The Space Book, The Interstellar Age, The Ultimate Interplanetary Travel Guide and Hubble Legacy. He served as president of The Planetary Society from 2008 to 2020 and received the American Astronomical Societys Carl Sagan Medal for public communication in science.

Tonights lecture is co-sponsored by the Foothill College Science, Tech, Engineering & Math Division; the SETI Institute; the Astronomical Society of the Pacific; and the UC observatories.

To view Bells presentation, visit youtube.com/SVAstronomyLectures. A recording will be made available at a later date. Past lectures in the series are accessible at the link above, and as podcasts at buzzsprout.com/1805595.

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Foothill College tonight hosts virtual astronomy lecture on Mars rovers - Los Altos Town Crier

This past March, UT-Austin astronomer Dr. Caitlin Casey was in the sleepless haze of early motherhood, holding a two-month-old baby on her lap, when she received an email akin to winning the scientific lottery. Cycle One JWST Notification Letter, was the subject line. Opening it, she read, We are pleased to inform you that your James Webb Space Telescope Cycle one proposal title Cosmos Webb has been approved...

She didnt need to read further. Approved! She knew what this meant. She slammed her laptop shut and messaged her colleague Jeyhan Kartaltepe, an astrophysicist at the Rochester Institute of Technology. We got itoh my God, we got it, Casey typed.

No! Kartaltepe responded, dumbfounded.

What Casey got was the largest project on the new, long-awaited James Webb Space Telescope, which is scheduled to launch from French Guiana on December 18. The worlds most powerful telescope, the Webb is expected to transform the way we understand the universe. Naturally, astronomers from around the world, hoping for precious research hours, sent proposals to the Space Telescope Science Institute (STScI). In its March email, the center granted Casey and her team more time than any other group.

At 36 years old, only eleven years after getting her PhD, Casey is relatively young to be awarded such a distinction. But she had other reasons to be surprised. Her proposal, the COSMOS-Webbwhich she and Kartaltepe wrote together over the pandemic, in Zoom conversations with dozens of colleagues who would work on the project with them across the globewas almost absurdly ambitious. Whereas the conventional wisdom with the Webb telescope was to look deeply at a tiny portion of sky the size of a pinpoint held at arms length, Casey and Kartaltepe asked to see a patch considerably larger, the size of three full moons on an average night. The STScI granted them 218 hours, or roughly eight days, of telescope time. (Most programs are in the six-hour range, she says.) If all goes well, the resulting images and data will step right up to the doorstep of the Big Bang, nearly 14 billion years ago, to show the magical but mysterious period when a dark, soupy mess of atoms were ionized by the first sources of light.

I met Casey this past October in her small office, on the sixteenth floor of UTs towering Physics, Math, and Astronomy Building, where a giant dry-erase board that covered nearly half a wall was filled with equations. She is quick to teach, easily drawing analogies that a layperson can understand, and she exudes an excitement that even several cups of coffee could not manufacture, laughing readily as if shes sharing thrilling gossip while saying things like, We get to think about the beginning of time itself, right?

When Casey first focused on the obscure early universe for her PhD, which she earned at the University of Cambridge in 2010, most of what we knew was shaped by the NASA Hubble Space Telescopethe groundbreaking equipment that primarily measured starlight. Using the Hubble, astronomers could see starlight clear across the observable universe, including images dating almost as far back as the Big Bang. But not quite far enough to see those earliest years. (One of the more mind-blowing things about powerful telescopes is that they allow for a kind of time travel: since light from far away takes many years to reach Earth, and the universe is expanding, the Webb will show us images from the universes history as it probes deeper and deeper into space.) We think we have a pretty good idea of how things went in the past ten, eleven billion years, Casey says. But its those first few billion years where you start to get really interesting questions that challenge our idea of how physics works. A lot of the big-picture questions are a little bit like a chicken-and-egg problem.

Cosmically, the chicken-and-egg problem goes like this: We know that stars are born from gas, and that gas condenses after stars die, starting the cycle over. But how, scientists want to know, did that process begin? The Hubble provided images of a few early galaxiesthe oldest being 400 million years after the Big Banggiving astronomers a glimpse into what that era might have looked like. Still, the sample was too small to reach definitive conclusions. To further explore that period, astronomers needed a telescope that was primarily operational at infrared wavelengths, as the light from the distant galaxies is stretched on its journey to us, or red-shifted, into infrared.

Enter the revolutionary James Webb Space Telescope. Casey was about eleven years old in 1996, when scientists formally recommended an infrared telescope as NASAs next major project. Over the ensuing decades, a team of more than 1,200 scientists and engineers from fourteen countries has been pushing the limits of technology to create it. Operating at a frigid negative 370 degrees Fahrenheit, so that its infrared sensors can function, the $9.7 billion observatory will set itself up in space after launch, unfurling its eighteen hexagonal mirrors coated in gold one million miles from Earth. It has to work perfectly; if anything goes wrong, the telescope will be too far away for repair. Were all very nervous about that, Casey says, noting that the telescopes sunshield layers, which block the suns interfering light and heat, are as thin as single human hairs. Oh gosh, its so scary to me. Yeah, Im glad I dont work on that or have to think about that.

Casey, like all astronomers, has been anticipating the Webbs arrival for years. The Webb will multiply by orders of magnitude the number of galaxies we can see from the earliest eras of the universe. It will also provide clearer data on some of the biggest astronomical questions, such as those concerning star life cycles, galaxy behavior over time, planets outside our solar system, and evidence of life beyond Earth. Using the telescope as it was intended, most of the research will focus on tiny spots and go as deep as possible. (This is the case with Caseys UT colleague Steven Finkelstein, who will be studying the early epoch of light for around one hundred hours for the Webb Deep Extragalactic Exploratory Public [WDEEP] Survey.)

But Caseys unconventional proposal sold the idea that instead of going narrowly into a deep field, it was important to have more context and survey a wide area, patching together a mosaic. Describing the structure of the universe as spongelike, she explains that some areas are like pockets, or empty voids with no galaxies, while other areas are like knots that have thousands of densely packed galaxies. Without a wider perspective, a single point in space could lead to the wrong conclusions. You might think that, Well, oh, you know, galaxies just dont exist at that time in the universes history, she says. But you could have landed on a void.

While the bulk of her observations arent scheduled to take place until April of 2023, Caseys preparations are well underway. Shell be gathering data from observatories around the world to prepare for when she receives the long-awaited images and data. What she predicts shell find, when this survey is taken over eight critical days, is about a million galaxiesfour to five thousand of which formed in the epoch of reionization. Several hundred million years after the Big Bang, when the universe was mostly composed of neutral hydrogen, cooling and expanding, gas clouds began to collapse under their own gravity and form stars that slowly but surely turned a very foggy place into a clearer one where light traveled freely. We can use that data to refine our models of how we think the universe actually formed, Casey says. Yeah. Its a big deal.

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The Most Powerful Telescope Ever Made Will Launch Next Month. A Texas Astronomer Is Leading Its Biggest Project. - Texas Monthly

In this serieswe are exploring the weird and wonderful world of astronomy jargon! Get a good look at todays topic: the cosmic microwave background!

The cosmic microwave background, or CMB, is all around you. Indeed, its by far the brightest object in the entire universe, responsible for over 99% of all photons.

And its a baby picture of the universe.

When our cosmos was very young, it was much smaller, hotter, and denser than it is today. Indeed it was so hot and dense that all the matter in the universe was a plasma, with the electrons ripped out of atoms and constantly mixed up with the high-energy radiation that soaked the universe at the time.

But when our universe was about 380,000 years old, it cooled to the point that the electrons could settle into their little atomic homes, turning our cosmos into a neutral gas of hydrogen and helium. That left all the radiation hanging around with nothing to do, so off it went.

At the time it was released, that radiation was literally white-hot. But as the ages passed, our universe expanded. That radiation cooled, and its wavelength stretched. All the way down to where it today, 13.8 billion years later, in the microwave part of the electromagnetic spectrum.

The CMB was discovered accidentally in the 1960s once we finally developed sensitive microwave detectors. It confirms that the general story of the big bang is accurate; there are no other theories of cosmology that can explain its existence.

Today, astronomers work with detectors on the ground and in space to make accurate maps of the CMB. The latest all-sky map comes courtesy of the Planck telescope, which was a joint venture between NASA and the ESA. Those maps reveal tiny little temperature differences, no bigger than one part in a million.

Those temperature differences tell us what the universe was like billions of years ago. The temperature differences tell us that the universe wasnt perfectly uniform there were also tiny differences in density. Those little seeds would eventually grow up to become galaxies, groups, and clustersthe largest structures in the universe today.

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Astronomy Jargon 101: Cosmic Microwave Background - Universe Today

There's too many satellites, space junk around Earth

Astronomers are raising the alarm on the number of satellites orbiting Earth and say if nothing is done to regulate how many get launched in the future, it could be detrimental for not just the environment on Earth, but space as well.

Astronomers are raising the alarm on the number of satellites orbiting Earth and say if nothing is done to regulate how many get launched in the future, it could be detrimental for not just the environment on Earth, but space as well.

There are thousands of satellites currently orbiting the planet and there are a couple thousand more that are inactive and are slowly making their way back down.

Starlink, which is part of SpaceX, has the most in orbit, according to Science.org. The company has launched more than 1,700 satellites so far and it plans to send tens of thousands more into space in the future.

On top of the satellites mucking up the night sky for astronomers, millions of tiny pieces of reflective debris from various collisions are making looking for important celestial bodies even harder.

"For the most part, I think almost all observatories around the world will be affected to some degree. Some less than others," said Connie Walker, a scientist for the NSFs National Optical-Infrared Astronomy Research Laboratory.

The background image shows the double star Albireo in Cygnus and was taken on Dec. 26, 2019. Two out of ten 2.5-minute exposures recorded Starlink satellites moving across the field.

RELATED: NASA launches satellite that will track Earths health

Astronomers across the world started more seriously raising the alarm on the vast amount of satellites and space junk orbiting the planet in May 2019 when Starlink launched its first 60 satellites into space.

"Astronomers went, Ah! Oh my gosh! We didnt know this was happening," Walker said with a chuckle. "Of course, SpaceX didnt keep it a secret but it wasnt really advertised to the level that astronomers picked up on."

But satellites have been a constant nuisance for astronomers even before SpaceXs massive launch.

Depending on where you are in the world, an astronomer may see a couple hundred satellites pass across their viewing area, according to Walker.

"For me, during the whole night, probably a thousand satellites go across but you dont see a lot of them. They have to be pretty much lit by the sun during the twilight hours and that could range up to a good fraction of the night depending on what time of year it is. For instance, if its the summertime, its (night) shorter, so you have more twilight higher in latitude and due to that, youre not in Earths shadow so they do get seen," Walker said.

RELATED: Vice President Kamala Harris to convene 1st National Space Council meeting Dec. 1

Images taken from telescopes around the world often capture the "tracks" or "trails" of the passing satellites and will create lines, basically rendering images unusable for scientific purposes.

"You see a pinpoint going across the sky with your eye, but when you open a camera onto the sky it becomes a trail. And not only does it become a trail, but that trail can have significant consequences on the image," according to Walker.

Observations with DECam on the Blanco 4-meter telescope at the Cerro Tololo Inter-American Observatory (CTIO), a Program of NSF's NOIRLab, astronomers Clara Martnez-Vzquez and Cliff Johnson noticed something interesting. One of their images, the 33 (CTIO/NOIRLab/NSF/AURA/DECam DELVE Survey)

And while the issue doesnt seem like much now, Walker believes the lack of regulation in regards to space and how humans use it could prove problematic in the future.

"It is a business. The companies are a business, theyre trying to make money but they also have a goal in mind too and whether you believe it or not, one goal is to bring broadband internet to the world. Like, were Zooming right now, because its going through a satellite and Im able to talk with you and were hundreds of miles apart. Thats pretty amazing," Walker said.

"But, its like plastics. Plastics were like the best thing since sliced bread and we just went ahead and we mass-produced all this stuff from plastics for various reasons, whether they were bottles or whatever they were, even medical equipment. It was the coolest thing on Earth. But disposing them, no one thought that through and its not biodegradable. Were harming our environment, were harming our space environment now and its harming people on Earth in various ways," Walker said.

RELATED: Russia rejects blame for space debris endangering 7 astronauts aboard ISS

Walker believes that while the goal appears noble, not everyone is thinking of the potential negative consequences that could emerge from hurling hundreds of thousands of satellites into the sky.

Rwanda hopes to launch more than 330,000 satellites into space in the decades to come in order to increase the nations access to the internet, according to Walker.

She said Rwandas request, which was made to the International Telecommunications Union in October, is daunting considering how many satellites are already floating around our planet.

"But still, its alarming to have that many up there. Thats much, much more than we have totally right now but, that said, when you look at all of the other companies like Amazon with their corporate project and One Web, based in the U.K., youve got to be well up into the tens of thousands by the end of the decade and over 100,000 with all the other companies included," Walker continued.

And the goal to provide internet to everyone on the planet is not the only motivator to launch more satellites.

RELATED: Longest partial lunar eclipse for 1,000 years to dazzle skywatchers on Nov. 19

In late September, NASA launched the Landsat 9 satellite into space which aims to track the "health" of the planet.

"The Landsat mission is like no other," said Karen St. Germain, director of the Earth Science Division at NASA Headquarters in Washington. "For nearly 50 years, Landsat satellites observed our home planet, providing an unparalleled record of how its surface has changed over timescales from days to decades. Through this partnership with USGS, weve been able to provide continuous and timely data for users ranging from farmers to resource managers and scientists. This data can help us understand, predict, and plan for the future in a changing climate."

Meanwhile, on Nov. 5, Vice President Kamala Harris announced that she, along with other leaders of the Biden administration, will hold an inaugural National Space Council meeting on Dec. 1.

"At that meeting, we will outline a comprehensive framework for our nation's space priorities. From our civilian efforts like those we have seen today to our military and national security efforts to STEM education and emerging space economy and what is abundantly clear is that when it comes to our space activity, there is limitless potential," Harris said during a visit to NASA's Goddard Space Center.

Harris also highlighted the work being done by Landsat 9 which joined its sister satellite, Landsat 8, and the pair work in tandem to "collect images spanning the entire planet every eight days," according to NASA.

RELATED: NASA: Asteroid the size of Empire State Building to whiz close by Earth in coming days

With more satellites come more chances for collisions, and with more collisions comes more debris making it hard for astronomers to accurately see whats going on in the space around Earth and beyond.

The millions of pieces of tiny space debris can actually add to the light pollution already plaguing the planet. "And raise the levels of how bright the night sky is so for people and animals, and whomever that depend on the night sky, that can be a factor," Walker said.

"Astronomers really are going to lose the twilight hours, I think. They do their best research on near-Earth asteroids at that time because its the time of night you can see asteroids better. Those kind of hours will be brightened significantly," Walker said.

This image of Venus and the Pleiades also shows the tracks of the Starlink satellites. These satellites which are located at an altitude of approximately 550 kilometers, are part of an ever-growing constellation of satellites aimed to provide worldwi (Torsten Hansen/IAU OAE via the International Astronomical Union)

"So, its starting to get alarming because safety is a big issue up there and collisions can produce a lot of problems in terms of safety in other things," Walker said.

On Monday, a Russian weapons test created more than 1,500 pieces of space junk now threatening the seven astronauts aboard the International Space Station, according to U.S. officials who called the strike reckless and irresponsible.

RELATED: Liftoff! SpaceX launches batch of Starlink satellites into orbit

The State Department confirmed that the debris was from an old Russian satellite destroyed by the missile.

"Needless to say, Im outraged. This is unconscionable," NASA Administrator Bill Nelson told the Associated Press. "Its unbelievable that the Russian government would do this test and threaten not only international astronauts, but their own cosmonauts that are on board the station" as well as the three people on China's space station.

Nelson said the astronauts now face four times greater risk than normal. And that's based on debris big enough to track, with hundreds of thousands of smaller pieces going undetected "any one of which can do enormous damage if it hits in the right place."

According to Walker, Russias alleged actions were highly dangerous, but there was no one around to tell them they couldnt do it and that is the problem.

"At this point in time, theres no one really out there that can say, You cant do that." Walker said. "They needed target practice, I guess, but it should have gone through some proper channels. But what are those proper channels?"

RELATED: Eiffel Tower-sized asteroid to fly past Earth next month

Until there is a governing body that can reprimand and "police" space, Walker said the next best thing astronomers have is communicating with companies and countries directly.

"Were actually working with companies, which is the best thing of all. To be able to work with the companies, and theres three companies that were working with right now and were trying to add to that list and theyre being pretty amenable about working with us. Although they cant always promise changes, and I can totally understand that," Walker said.

"We started communicating every single month for about a year with SpaceX, which was wonderful. And it was through the relationships they had with the Ruben Observatory that some solutions were actually made," Walker continued.

The Ruben Observatory, which is located in Chile, is expected to start operating within the next year and aims to observe and study dark energy and dark matter, take an inventory of the solar system, explore the transient optical sky and map the Milky Way, according to the observatorys website.

"They first darkened one or two of the satellites and then tried more," Walker said. SpaceX then put visors on their satellites to prevent certain parts from reflecting too much sunlight. While the effort proved effective, science and technology are continuing to evolve at a rapid pace and SpaceXs once-lauded solutions are now not having the same impacts as they once were.

RELATED: NASA targeting February for launch of first moon rocket since Apollo mission

"Now they want to have these inter-satellite communications with lasers so theyre going to have to take away the visors. So that was a solution that brought us almost up to the point where we could say, Alright, well still have main street, well get rid of the residual effects that you see on the image, but now its like two steps backwards," Walker continued.

Despite that setback, Walker said companies are trying to find solutions. Companies such as Amazon and One Web have approached the astronomical society to find a happy middle for both businesses and scientists.

"Theres so many things to think about and readjust," Walker said. "But then you also look at, can these things actually be done?"

The goal for both companies and astronomers is to determine the most reasonable solution that wont break the bank.

Could there be a type of software that will eliminate any unwanted images from telescopes? Could there be someone whose sole job is to actively avoid catching satellites on telescopes? Or could companies possibly launch their satellites out of the line of sight of observatories? The answers to all of these questions is "not totally," according to Walker.

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"The question, too, is: Are we going to be funded?" Walker said.

Walker said funding is already scarce in the realm of astronomy, so, adding another financial hurdle like how to efficiently move satellites from scientists line of sight is making things tighter than they are already are.

"The happy middle is that they (companies) have to really have a stringent plan for how many can launch, how many can be up there, what their deorbit time is because they can build in when they have to deorbit," according to Walker.

"No ones going to go up there and bring the satellites down, its just too expensive. And the deorbit, the higher you go, the longer it takes to deorbit. So, it could take 100 years for something thats a thousand kilometers up there. It could take five years for something thats maybe at 600 or less kilometers if you build it in, but usually its something around 25 years. Satellites stay up there longer than their usefulness, basically. Because, they get used for five years then theyre antiquated," Walker said.

When putting a satellite into deorbit, Walker said, companies must consider the size and materials because once the satellite comes hurtling back through Earths atmosphere, depending on the materials used, it could either burn up or crash into a populated area and hurt people.

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"They (companies) have to go beyond what they have now and have a solid plan for deorbiting," Walker said.

Walker said apart from having a solid and safe plan to get useless satellites out of the sky, a broader dialogue about the issue needs to be initiated.

"We need a stronger relationship with the different companies and to work with them even more closely," she added.

Walker said there are some who believe there should be an absolute halt to any more satellite launches in the future, and while Walker acknowledges thats not possible, she said there needs to be accountability. Those who are launching satellites need to do their due diligence to ensure theyre doing everything they can to deflect any negative impacts satellites and space trash have.

"And in some ways, thats not unreasonable. You want to think things through. Its not like we dont want it to happen, we just want to think things through and come up with solutions before we make it worse, as we should have done with plastics," Walker said.

"This is our only spaceship," Walker said. "We have to be good stewards otherwise well create irreparable problems. Better start now."

The Associated Press contributed to this report. This story was reported out of Los Angeles.

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Thousands of satellites, space junk surround Earth and its a problem, astronomers say - FOX 10 News Phoenix