Tag Archives: observatories and telescopes

Exoplanets: The search for habitable planets may have just narrowed

October 25, 2022 Admin Leave a comment

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The hunt for planets that could harbor life may have just narrowed dramatically.

Scientists had long hoped and theorized that the most common type of star in our universe — called an M dwarf — could host nearby planets with atmospheres, potentially rich with carbon and perfect for the creation of life. But in a new study of a world orbiting an M dwarf 66 light-years from Earth, researchers found no indication such a planet could hold onto an atmosphere at all.

Without a carbon-rich atmosphere, it’s unlikely a planet would be hospitable to living things. Carbon molecules are, after all, considered the building blocks of life. And the findings don’t bode well for other types of planets orbiting M dwarfs, said study coauthor Michelle Hill, a planetary scientist and a doctoral candidate at the University of California, Riverside.

“The pressure from the star’s radiation is immense, enough to blow a planet’s atmosphere away,” Hill said in a post on the university’s website.

M dwarf stars are known to be volatile, sputtering out solar flares and raining radiation on nearby celestial bodies.

But for years, the hope had been that fairly large planets orbiting near M dwarfs could be in a Goldilocks environment, close enough to their small star to keep warm and large enough to cling onto its atmosphere.

The nearby M dwarf, however, could be too intense to keep the atmosphere intact, according to the new study, which was published in The Astrophysical Journal Letters.

A similar phenomenon happens in our solar system: Earth’s atmosphere also deteriorates because of outbursts from its nearby star, the sun. The difference is that Earth has enough volcanic activity and other gas-emitting activity to replace the atmospheric loss and make it barely detectable, according to the research.

However, the M dwarf planet examined in the study, GJ 1252b, “could have 700 times more carbon than Earth has, and it still wouldn’t have an atmosphere. It would build up initially, but then taper off and erode away,” said study coauthor and UC Riverside astrophysicist Stephen Kane, in a news release.

GJ 1252b orbits less than a million miles from its home star, called GJ_1252. The planet reaches sweltering daytime temperatures of up to 2,242 degrees Fahrenheit (1,228 degrees Celsius), the study found.

The existence of the planet was first suggested by NASA’s Transiting Exoplanet Survey Satellite, or TESS, mission. Then, astronomers ordered the nearly 17-year-old Spitzer Space Telescope to set its sights on the area in January 2020 — less than 10 days before Spitzer was deactivated forever.

The investigation into whether GJ 1252b had an atmosphere was led by astronomer Ian Crossfield at the University of Kansas and involved a collection of researchers from UC Riverside, NASA’s Jet Propulsion Laboratory, Caltech, the University of Maryland, Carnegie Institution for Science, the Max Planck Institute for Astronomy, McGill University, the University of New Mexico, and the University of Montreal.

They pored over the data produced by Spitzer, searching for emission signatures, or signs that a gaseous bubble could encase the planet. The telescope captured the planet as it passed behind its home star, allowing researchers to “look at the starlight as it’s passing through the atmosphere of the planet,” giving a “spectral signature of the atmosphere” — or lack thereof, Hill said.

Hill added that she wasn’t shocked to find no signs of an atmosphere, but she was disappointed. She’s looking for moons and planets in “habitable zones,” and the results made looking at worlds circling the ubiquitous M dwarf stars slightly less interesting.

Researchers hope to get even more clarity about these types of planets with the help of the James Webb Space Telescope, the most powerful space telescope to date.

Webb will soon set its sights on the TRAPPIST-1 system, “which is also an M dwarf star with a bunch of rocky planets around it,” Hill noted.

“There’s a lot of hope that it will be able to tell us whether those planets have an atmosphere around them or not,” she added. “I guess the M dwarf enthusiasts are probably holding their breath right now to see whether we can tell whether there’s an atmosphere around those planets.”

There are, however, still plenty of interesting places to hunt for habitable worlds. Apart from looking to planets farther away from M dwarfs that could be more likely to retain an atmosphere, there are still roughly 1,000 sunlike stars relatively near Earth that could have their own planets circling within habitable zones, according to the UC Riverside post about the study.

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Webb telescope observes whirling stars create dust rings

October 12, 2022 Admin Leave a comment

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A new image captured by the James Webb Space Telescope shows rings of dust plumes created by the violent interactions between two stars.

The image is part of new research that reveals how intense starlight can push matter around in space by focusing on a double-star system located 5,000 light-years away from Earth in the Cygnus constellation.

The star system, called WR140, includes a Wolf-Rayet star and a blue supergiant star swirling around one another in an orbit that takes eight years to complete. The blue supergiant is an O-type star, one of the most massive star types known. Only some massive stars evolve into a Wolf-Rayet as they approach the end of their life cycle. This stage lasts a few hundred thousand years.

Astronomers have observed the binary star system for two decades using the W.M. Keck Observatory in Hawaii.

Every eight years when the stars come close together, they release dust plumes that stretch thousands of times the distance between Earth and the sun. Researchers observed the plumes to measure how starlight can impact matter for their study published in the journal Nature on Wednesday.

Light can exert a type of momentum called radiation pressure on matter, but it’s difficult to spot in space.

“It’s hard to see starlight causing acceleration because the force fades with distance, and other forces quickly take over,” said first study author Yinuo Han, doctoral student at the University of Cambridge’s Institute of Astronomy in the United Kingdom, in a statement.

“To witness acceleration at the level that it becomes measurable, the material needs to be reasonably close to the star or the source of the radiation pressure needs to be extra strong. WR140 is a binary star whose ferocious radiation field supercharges these effects, placing them within reach of our high-precision data.”

All stars generate their own stellar wind, or streams of gas blown out into space, but massive Wolf-Rayet stars can whip up winds into something more akin to a stellar hurricane. Wolf-Rayet stars in later stages of their life cycle have blown off their hydrogen layer. Hydrogen can’t form dust on its own, but other elements located in a star’s interior, like carbon, can.

Carbon condenses into sooty dust in the rapidly whirling wind, which glows in infrared light that is invisible to the human eye. But telescopes can spot this warm, glowing light.

The team’s observations revealed that the dust plumes form where the stellar winds from both of the giant stars collide, creating a cone-shaped shock front between the stars.

As the stars go through their oval-shaped orbit, the shock front also moves, which causes the smoke-like dust plume to spiral. If the stars had a circular orbit, it would form a pinwheel pattern. Instead, the oval-shaped orbit creates delays in dust production that cause the dust plumes to resemble rings or shells.

The end result resembles an uneven bull’s-eye or something that looks like a spiderweb.

The Webb telescope was able to peer much deeper into the binary star system than ground-based telescopes and observed almost 20 accelerating dust plumes nested inside each other. The journal Nature Astronomy published the results of the Webb observation on Wednesday.

“Like clockwork, this star puffs out sculpted smoke rings every eight years, with all this wonderful physics written then inflated in the wind like a banner for us to read,” said study coauthor Peter Tuthill, a professor at the School of Physics at The University of Sydney, in a statement.

“Eight years later as the binary returns in its orbit, another appears the same as the one before, streaming out into space inside the bubble of the previous one, like a set of giant nested Russian dolls.”

The predictable production of a dust plume every eight years in the star system provided researchers with the perfect target to study the expansion rate of each dust spiral. Rather than expanding a constant speed, they were observed accelerating.

“In one sense, we always knew this must be the reason for the outflow, but I never dreamed we’d be able to see the physics at work like this,” Tuthill said. “When I look at the data now, I see WR140’s plume unfurling like a giant sail made of dust. When it catches the photon wind streaming from the star, like a yacht catching a gust, it makes a sudden leap forward.”

Webb’s sensitivity will allow astronomers to make more observations of Wolf-Rayet stars and their intriguing physics in the future, according to the study authors.

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Pair of galaxies shine in new image from Webb, Hubble telescopes

October 5, 2022 Admin Leave a comment

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When astronomers combine the observational powers of James Webb Space Telescope and Hubble Space Telescope, they capture more detailed portraits of the cosmos.

A new image showcasing a galactic pair, shared by NASA on Wednesday, is the striking result of using data from both space observatories.

The telescopes each contributed observations across different wavelengths of light. Webb can detect infrared light, which is invisible to the human eye, while Hubble has the capability to observe the two galaxies in visible light as well as ultraviolet light. The duo of the elliptical galaxy and the spiral galaxy is known as VV 191, and it’s located about 700 million light-years away from Earth.

“We got more than we bargained for by combining data from NASA’s James Webb Space Telescope and NASA’s Hubble Space Telescope!” wrote Webb interdisciplinary scientist and Arizona State University Regents Professor Rogier Windhorst for NASA’s Webb blog.

“Webb’s new data allowed us to trace the light that was emitted by the bright white elliptical galaxy, at left, through the winding spiral galaxy at right — and identify the effects of interstellar dust in the spiral galaxy. … Webb’s near-infrared data also show us the galaxy’s longer, extremely dusty spiral arms in far more detail, giving the arms an appearance of overlapping with the central bulge of the bright white elliptical galaxy on the left.”

The image is an early result from the observation program called the Prime Extragalactic Areas for Reionization and Lensing Science, or PEARLS, through the Webb Telescope, which has not yet been through the peer-review process. The study has been submitted to The Astrophysical Journal.

Scientists selected the galactic pair from nearly 2,000 candidates identified by Galaxy Zoo citizen science volunteers. These small galaxies, which appear to be very close together, aren’t actually interacting with one another, but they allow researchers to trace and compare galactic dust.

“Understanding where dust is present in galaxies is important, because dust changes the brightness and colors that appear in images of the galaxies,” Windhorst wrote. “Dust grains are partially responsible for the formation of new stars and planets, so we are always seeking to identify their presence for further studies.”

But a closer look at this galactic pair isn’t the only celestial wonder this composite image revealed. Other galaxies are also visible behind the pair, and one of these points of light led to a second discovery within the new image. This phenomenon, called gravitational lensing, occurs when foreground galaxies act as a magnifying glass for the objects behind them.

Scientists used the same technique for Webb’s first image released in July. The space telescope “delivered the deepest and sharpest infrared image of the distant universe to date,” according to NASA.

Above the white elliptical galaxy to the left is a faint red arc, which is actually a very distant galaxy. The gravity of the elliptical galaxy in the foreground has bent the more distant galaxy’s light. The warping of the distant galaxy also causes it to reappear as a red dot to the lower right of the elliptical galaxy.

The images of the distant galaxy are so faint that they weren’t recognized in the Hubble data, but they appear clearly in Webb’s near-infrared observation.

“Simulations of gravitationally lensed galaxies like this help us reconstruct how much mass is in individual stars, along with how much dark matter is in the core of this galaxy,” Windhorst wrote.

Beyond the insights astronomers are gleaning about VV 191, the background of this Webb image hints at more mysteries deeper in the universe yet to be revealed, he added. “Two patchy spirals to the upper left of the elliptical galaxy have similar apparent sizes, but show up in very different colors. One is likely very dusty and the other very far away, but we — or other astronomers — need to obtain data known as spectra to determine which is which.”

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Dramatic images show spacecraft collision with an asteroid

October 1, 2022 Admin Leave a comment

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The DART mission made history this week when it successfully slammed into an asteroid – and we got to see it happen live, from millions of miles away.

As the spacecraft for NASA’s Double Asteroid Redirection Test neared its target Monday, images streamed back to Earth at the rate of one per second of the asteroid Dimorphos, which orbits a larger space rock called Didymos.

Each image proved better than the last, and in the seconds before DART’s impact with Dimorphos, the surface of the small moon filled the entire frame.

Dimorphos, which had never been seen before, turned out to be egg-shaped and covered in boulders. The rocky asteroid has surprised scientists, who are eager to study the images captured by DART before it crashed in a blaze of glory.

Researchers estimate it will take about two months to determine whether DART was successful in changing Dimorphos’ motion in space in humanity’s first test of asteroid deflection technology.

The spacecraft may have shared an incredible first look at an asteroid, but it’s not the only perspective of that asteroid system we’ve been fortunate enough to see.

All eyes were on Didymos and Dimorphos to get a glimpse of the DART impact and aftermath, and the early images did not disappoint.

The Hubble Space Telescope and James Webb Space Telescope both observed the collision and spied plumes of material releasing from the surface of Dimorphos.

Ground-based observatories also shared how bright the asteroid system became after being dinged by DART.

But the most dramatic images were the first ones shared by LICIACube, the mini Italian satellite that followed DART and watched the entire event from a safe distance. The best part? We’re going to see so much more over the next two months.

The Nobel committee will soon announce the recipients of its annual prizes next week.

It’s difficult to predict who will win these prestigious awards because the nominators, short list and the selection process are kept from public view.

In 2021, none of the Nobel laureates for sciences were women, which some critics suggested was more evidence of systemic bias in scientific fields.

But there are plenty of women who are worthy candidates, such as Dr. Mary-Claire King, who discovered cancer-causing genes, and Dr. Marilyn Hughes Gaston, whose work blazed a trail in treating sickle cell disease.

Meet more of the female scientists on CNN’s list and learn about the revolutionary discoveries they’ve made in vaccine research, astronomy and chemistry.

Popping fireworks, sizzling bacon and extended booms of thunder are just some of the sounds associated with Earth’s massive glaciers as they fracture and shrink.

Scientists are tuning in to the surprisingly noisy nature of glaciers to learn how quickly ice is melting amid the climate crisis – and to uncover mysteries of the deep.

Glacial ice can be very fizzy, hissing as it releases pressurized air and bubbles that have been frozen for hundreds or even thousands of years.

Where glaciers meet the ocean can be a dangerous place for humans. Monitoring the acoustics of these dense bodies of ice from afar is changing how researchers understand them and what we know about how their sounds impact the animals living in these disappearing habitats.

More than 100 years after the SS Mesaba sank, scientists have found its wreckage at the bottom of the Irish Sea.

On April 14, 1912, the British merchant steamship had sent a message to the RMS Titanic, but the iceberg warning never reached the massive ocean liner’s main control center on that fateful night.

A German submarine torpedoed the Mesaba just six years later, resulting in the death of 20 people. But the exact location of the vessel has been unknown until now.

Researchers used sonar surveying to find the Mesaba – along with a multitude of other shipwrecks strewn across 7,500 square miles (19,425 kilometers).

Galaxies far, far away seem to be putting on a scintillating show for the James Webb Space Telescope.

Webb spotted the “bones” of a stunning spiral galaxy located 29 million light-years from Earth, a feat even more surprising when compared with Hubble’s view of the same galaxy.

Meanwhile, astronomers analyzed Webb’s very first image and determined that it contains some of the oldest stars and galaxies in the universe – including one that looks a lot like a celestial firework.

The Sparkler galaxy is surrounded by glittering yellow and red dots, some of which turned out to be clusters of ancient stars.

Linger a little longer over these stories:

– The Hubble Space Telescope may get a boost into a higher orbit to extend its life, depending on the findings under a new exploratory agreement between NASA and SpaceX.

– Dogs are endearing for many reasons, and now there’s scientific evidence shedding more light on one of their impressive scent-detecting skills.

– The NASA Juno spacecraft flew by Jupiter’s moon Europa and captured a stunning new look at the ice-covered ocean world.

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NASA, SpaceX to study boosting Hubble telescope to higher orbit

September 29, 2022 Admin Leave a comment

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Officials at NASA have signed a Space Act Agreement with SpaceX to investigate the benefits and risks of having a private mission provide service to NASA’s nearly 33-year-old Hubble Space Telescope, boosting it to a higher orbit to extend its life, the space agency announced Thursday.

“Hubble is amazingly successful. … It’s doing great science as we speak,” said Thomas Zurbuchen, associate administrator of NASA’s Science Mission Directorate, during a news conference.

But SpaceX approached the space agency a few months ago with the idea, he said, and the team at NASA is now planning to assess how a private mission might help “boost” and maintain the telescope.

Zurbuchen added that it is not yet certain whether or not such a mission could be carried out, and the goal of the agreement is just to explore the technical feasibility of the idea.

Jessica Jensen, vice president of customer operations and integration at SpaceX, said the private aerospace company “has a lot of experience docking (spacecraft) with the International Space Station.”

SpaceX wants to use that knowledge as a foundation and find out whether it’s possible to carry out a similar docking maneuver with the Hubble telescope, Jensen said.

It could be done at “no cost to the government,” according to a NASA news release. The Space Act Agreement itself will not involve any exchange of funds, according to the release.

Launched in 1990, the space observatory has had several servicing missions during NASA’s space shuttle era, with the last mission carried out in 2009. But the space agency retired the space shuttle in 2011, and no spacecraft has been back since.

SpaceX’s Crew Dragon spacecraft missions have already taken over much of the work that the space shuttle program used to carry out, including ferrying astronauts to and from the ISS.

The effort to send a private mission to Hubble could be a part of a previously announced, privately funded SpaceX program called Polaris. That program is the brainchild of Jared Isaacman, the billionaire CEO of payments platform Shift4, who first gained international attention when he paid the company to take himself and three guests on a three-day trip to orbit Earth aboard a SpaceX Crew Dragon capsule last year.

He announced the Polaris program in February, and at the time he said the program would encompass at least three missions with SpaceX.

The first flight in the program, called Polaris Dawn, is expected to last up to five days. It will include a crew of Isaacman and three other people, who will ride aboard a SpaceX Crew Dragon capsule to the Van Allen radiation belt, which has an inner band that stretches from about 400 to 6,000 miles (644 to 9,656 kilometers) above Earth. It’s scheduled to take off no earlier than March 2023.

The second Polaris mission could be a great candidate for sending a SpaceX capsule to Hubble, Isaacman said at Thursday’s news conference.

It’s not yet clear whether an autonomous, uncrewed spacecraft could carry out a Hubble service mission instead of requiring a crew on board, according to Jensen.

Zurbuchen added that is all part of what SpaceX and NASA will explore as part of this Space Act Agreement.

“We’re looking at crazy ideas all the time,” he said. “That’s what we’re supposed to do.”

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Spiral galaxy captured in ‘unprecedented detail’ by Webb telescope

September 27, 2022 Admin Leave a comment

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A dazzling spiral galaxy located 29 million light-years from Earth appears in “unprecedented detail” in a new image released by NASA’s James Webb Space Telescope.

The “bones” of the galaxy, typically obscured from view by dust, are on full display.

The galaxy, named IC 5332, stretches about 66,000 light-years wide, making it about one-third the size of our home galaxy, the Milky Way.

IC 5332 is “notable for being almost perfectly face-on with respect to Earth, allowing us to admire the symmetrical sweep of its spiral arms,” according to a press release from the European Space Agency.

To capture the image, the Webb telescope used its Mid-InfraRed Instrument, or MIRI, one of the observatory’s four powerful tools to investigate the cosmos, according to the release.

MIRI is the only Webb instrument that is sensitive to light on mid-infrared wavelengths, a type of wavelength that can only be observed by telescopes outside of Earth’s atmosphere. (Infrared is the term scientists use to refer to light that has wavelengths longer than humans can detect with the naked eye.)

The Hubble Space Telescope previously observed the galaxy in ultraviolet and visible light using its Wide Field Camera 3.

“The Hubble image shows dark regions that seem to separate the spiral arms, whereas the Webb image shows more of a continual tangle of structures that echo the spiral arms’ shape,” according to the release. The images reveal different stars, depending on the detectable wavelengths of each telescope.

The difference in a side-by-side comparison of the images is due to the galaxy’s dusty regions. Ultraviolet and visible light can be scattered by interstellar dust, so the dust-heavy regions appear darker in Hubble’s view.

Webb’s ability to detect infrared light can penetrate interstellar dust. Together, these two views of the same galaxy reveal more about its composition and structure.

To function, all of Webb’s instruments must be kept extremely cold, because even slightly warm objects can emit their own infrared light and distort an image. The MIRI instrument is kept the coldest at minus 447 degrees Fahrenheit (minus 266 degrees Celsius) – only 7 degrees Celsius warmer than absolute zero. (Absolute zero is the lowest possible temperature on the thermodynamic scale).

Meanwhile, the Webb team is assessing an issue with one of MIRI’s four observing modes.

“On Aug. 24, a mechanism that supports one of these modes, known as medium-resolution spectroscopy (MRS), exhibited what appears to be increased friction during setup for a science observation. This mechanism is a grating wheel that allows scientists to select between short, medium, and longer wavelengths when making observations using the MRS mode,” according to an update from the Webb blog run by NASA.

Observations in this mode have been paused by the Webb team as they determine a path forward. Otherwise, Webb, its instruments and MIRI’s other three observing modes are fine.

Webb is operated by NASA, ESA and the Canadian Space Agency. The $10 billion space observatory, launched last December, has enough fuel to keep taking fantastic images for about 20 years.

Compared with other telescopes, the space observatory’s massive mirror can see faint, distant galaxies and has the potential to enhance our understanding of the origins of the universe.

Some of Webb’s first images, released in July, have highlighted the observatory’s capabilities to reveal previously unseen aspects of the cosmos, like star birth shrouded in dust.

However, it’s also using its stable and precise image quality to illuminate our own solar system, and so far has taken images of Mars, Jupiter and Neptune.