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NASA’s Webb Telescope takes star-filled portrait of pillars of creation

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NASA’s James Webb Space Telescope has captured highly detailed landscape the Pillars of Creation where new stars are forming.

NASA’s James Webb Space Telescope has captured a lush, highly detailed landscape the iconic Pillars of Creation where new stars are forming within dense clouds of gas and dust. The three-dimensional pillars look like majestic rock formations but are far more permeable. These columns are made up of cool interstellar gas and dust that appear at times semi-transparent in near-infrared light.

Webb’s new view of the Pillars of Creation, which were first made famous when imaged by NASA’s Hubble Space Telescope in 1995, will help researchers revamp their models of star formation by identifying far more precise counts of newly formed stars, along with the quantities of gas and dust in the region. Over time, they will begin to build a clearer understanding of how stars form and burst out of these dusty clouds over millions of years.

Newly formed stars are the scene-stealers in this image from Webb’s Near-Infrared Camera (NIRCam). These are the bright red orbs that typically have diffraction spikes and lie outside one of the dusty pillars. When knots with sufficient mass form within the pillars of gas and dust, they begin to collapse under their own gravity, slowly heat up, and eventually form new stars.

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What about those wavy lines that look like lava at the edges of some pillars? These are ejections from stars that are still forming within the gas and dust. Young stars periodically shoot out supersonic jets that collide with clouds of material, like these thick pillars. This sometimes also results in bow shocks, which can form wavy patterns like a boat does as it moves through water. The crimson glow comes from the energetic hydrogen molecules that result from jets and shocks. This is evident in the second and third pillars from the top — the NIRCam image is practically pulsing with their activity. These young stars are estimated to be only a few hundred thousand years old.

Although it may appear that near-infrared light has allowed Webb to “pierce through” the clouds to reveal great cosmic distances beyond the pillars, there are no galaxies in this view. Instead, a mix of translucent gas and dust known as the interstellar medium in the densest part of our Milky Way galaxy’s disk blocks our view of the deeper universe.

This scene was first imaged by Hubble in 1995 and revisited in 2014, but many other observatories have also stared deeply at this region. Each advanced instrument offers researchers new details about this region, which is practically overflowing with stars.

This tightly cropped image is set within the vast Eagle Nebula, which lies 6,500 light-years away.

The James Webb Space Telescope is the world’s premier space science observatory. Webb will solve mysteries in our solar system, look beyond to distant worlds around other stars, and probe the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and CSA (Canadian Space Agency).

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Artemis 1 Orion spacecraft aced its test flight but still hasn't tested life support – Space.com

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The Europe-built service module powering the Orion spaceship during the Artemis 1 mission is nailing its debut lunar round trip, but a key system for keeping future human crews alive is not being tested during the flight. 

The Orion capsule, which commenced the return leg of its groundbreaking journey on Thursday (Dec. 1), is currently not filled with breathable air, European aerospace giant Airbus  told Space.com. According to Airbus, which built Orion’s service module, the capsule’s life support system will only be fully put through its paces in ground-based labs before the first flight with astronauts in 2024. 

The Europe-built service module, responsible for propulsion and navigation, is the part of the spacecraft that sustains livable conditions inside Orion’s crew compartment. The service module carries water the astronauts will need during the flight and generates breathable air by mixing oxygen and nitrogen that are stored in separate tanks.

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Related: NASA’s Artemis 1 moon mission: Live updates

During the Artemis 1 mission, however, engineers are only testing the nitrogen delivery system, but fortunately, neither Shaun the Sheep, the plush toy sent for the mission by the European Space Agency (ESA), nor the three dummies occupying the Orion cockpit, mind this fact. 

“The oxygen and nitrogen delivery systems are very similar,” Airbus spokesperson Ralph Heinrich told Space.com in an email. “We carry nitrogen on board Artemis 1 and will be testing the nitrogen delivery system during the flight that’s ongoing at the moment. As the oxygen and nitrogen systems carry the same components, the test on the nitrogen distribution system will cover by similarity the oxygen delivery system. Furthermore, the oxygen system is being tested extensively on ground.”

For Airbus, the Artemis 1 mission represents a major victory. The company was awarded a contract to develop the service module, a key component of the Orion spacecraft, by ESA, based on their previous experience building the Automated Transfer Vehicle, a cargo spacecraft which used to supply the International Space Station between 2008 and 2014. During its lunar sorties in the late 1960s and early 1970s, NASA built all of the required technology at home in the United States and didn’t include any international partners.

Shaun the Sheep fortunately doesn’t mind the absence of breathable atmosphere inside the Orion capsule during the debut Artemis 1 mission. (Image credit: ESA)

The Artemis 1 service module is a culmination of ten years of work, and the Airbus team is delighted to see the craft performing with flying colors. So far, the service module has completed all of its key tasks flawlessly, including three engine burns, which first helped Orion to enter orbit around the moon, and then to subsequently leave lunar orbit to head back to Earth.

In a post-launch press conference, NASA admitted it detected 13 anomalies during the early phase of Orion’s flight, including erratic readings from star trackers that the space capsule uses to navigate.

“Engineers will be looking into the data that’s coming back from Orion so that every single system, every single component on board of the spacecraft can be tested in one way or another before the next mission,” Sian Cleaver, the European Service module project manager at Airbus told Space.com in an interview. “So far, everything is going well. Of course, there’ll be things that can be improved or changed. There were a few things that didn’t work exactly as planned, but none of them were major issues.”

Airbus engineers are receiving a stream of data from the spacecraft including “pressure, temperature, valve position data and currents and voltages” to monitor its health, Airbus wrote in an email.

“We look at all the data throughout the whole mission, and especially during major events, like main engine firings,” Airbus wrote. “[We] make sure the system is operated within its expected and qualified range. The data is also being stored continuously, to allow post flight analyses and prepare for the next Artemis missions.”

Airbus has already delivered the next service module to NASA for testing and mating with the crew compartment for the Artemis 2 mission,which will take humans to orbit around the moon for the first time since the final Apollo flight in 1972. That mission is expected to launch no earlier than 2024, if all goes according to plan. The company has also nearly completed the assembly of the third service module, which will power the Artemis 3 mission that is expected to involve a lunar landing no earlier than 2025.

The bones of the fourth service module have also been put together and plans are in place to begin work on the fifth specimen later this month. These service modules will cover Artemis missions 4 and 5, which are expected to take off to the moon toward the end of this decade. By that time, the Lunar Gateway space station will be put together in orbit around the moon, opening a new era of regular human visits to Earth’s companion.

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“It really feels like a bit of a production line going on now at our facility,” Cleaver said. “It’s really exciting. The program is really, really moving now. We have a plan for the next 10 years, and there are also clear messages from NASA and ESA that the moon is only the first step and that the technology will be used to eventually go to Mars.”

Airbus is under contract to build the service module number six and is currently negotiating another batch of three. The service modules are single-use only and will detach from the crew capsule before it enters Earth’s atmosphere during its return. 

The Artemis 1 mission lifted off from NASA’s Kennedy Space Center in Florida on Nov. 16. The mission was a debut not only for Orion, but also for the Space Launch System mega rocket that lofted it into space. During the mission, Orion passed only 80 miles (130 kilometers) above the moon’s surface, and also broke a record for the greatest distance from Earth ever achieved by a human-rated spacecraft. By getting as far as 270,000 miles (435,000 km) from the planet, Orion surpassed the previous maximum held by the Apollo 13 mission. That mission, however, only got that far as part of a rescue operation designed to bring it back home after an onboard explosion crippled the spacecraft. 

Follow Tereza Pultarova on Twitter @TerezaPultarova. Follow us on Twitter @Spacedotcom and on Facebook

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NASA capsule flies over Apollo landing sites, heads home – World News – Castanet.net

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NASA’s Orion capsule and its test dummies swooped one last time around the moon Monday, flying over a couple Apollo landing sites before heading home.

Orion will aim for a Pacific splashdown Sunday off San Diego, setting the stage for astronauts on the next flight in a couple years.

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The capsule passed within 80 miles (130 kilometers) of the far side of the moon, using the lunar gravity as a slingshot for the 237,000-mile (380,000-kilometer) ride back to Earth. It spent a week in a wide, sweeping lunar orbit.

Once emerging from behind the moon and regaining communication with flight controllers in Houston, Orion beamed back photos of a close-up moon and a crescent Earth — Earthrise — in the distance.

“Orion now has its sights set on home,” said Mission Control commentator Sandra Jones.

The capsule also passed over the landing sites of Apollo 12 and 14. But at 6,000 miles (9,600 kilometers) up, it was too high to make out the descent stages of the lunar landers or anything else left behind by astronauts more than a half-century ago. During a similar flyover two weeks ago, it was too dark for pictures. This time, it was daylight.

Deputy chief flight director Zebulon Scoville said nearby craters and other geologic features would be visible in any pictures, but little else.

“It will be more of a tip of the hat and a historical nod to the past,” Scoville told reporters last week.

The three-week test flight has exceeded expectations so far, according to officials. But the biggest challenge still lies ahead: hitting the atmosphere at more than 30 times the speed of sound and surviving the fiery reentry.

Orion blasted off Nov. 16 on the debut flight of NASA’s most powerful rocket ever, the Space Launch System or SLS.

The next flight — as early as 2024 — will attempt to carry four astronauts around the moon. The third mission, targeted for 2025, will feature the first lunar landing by astronauts since the Apollo moon program ended 50 years ago this month.

Apollo 17 rocketed away Dec. 7, 1972, from NASA’s Kennedy Space Center, carrying Eugene Cernan, Harrison Schmitt and Ron Evans. Cernan and Schmitt spent three days on the lunar surface, the longest stay of the Apollo era, while Evans orbited the moon. Only Schmitt is still alive.

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By Looking Back Through Hubble Data, Astronomers Have Identified six Massive Stars Before They Exploded as Core-Collapse Supernovae – Universe Today

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The venerable Hubble Space Telescope has given us so much during the history of its service (32 years, 7 months, 6 days, and counting!) Even after all these years, the versatile and sophisticated observatory is still pulling its weight alongside more recent addition, like the James Webb Space Telescope (JWST) and other members of NASA’s Great Observatories family. In addition to how it is still conducting observation campaigns, astronomers and astrophysicists are combing through the volumes of data Hubble accumulated over the years to find even more hidden gems.

A team led by Caltech’s recently made some very interesting finds in the Hubble archives, where they observed the sites of six supernovae to learn more about their progenitor stars. Their observations were part of the Hubble Space Telescope Snapshot program, where astronomers use HST images to chart the life cycle and evolution of stars, galaxies, and other celestial objects. From this, they were able to place constraints on the size, mass, and other key characteristics of the progenitor stars and what they experienced before experiencing core collapse.

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The team was led by Dr. Schuyler D. Van Dyk, a senior research scientist with Caltech’s Infrared Processing and Analysis Center (IPAC). His teammates included researchers from the University of California, Berkeley, the Space Telescope Science Institute, the University of Arizona’s Steward Observatory, the University of Hawai’i’s Institute for Astronomy, and the School of Physics and Astronomy at the University of Minnesota. Their findings were published in a paper titled “The disappearance of six supernova progenitors” that will appear in the Monthly Notices of the Royal Astronomical Society.

The Hubble Ultra Deep Field seen in ultraviolet, visible, and infrared light. Image Credit: NASA, ESA, H. Teplitz and M. Rafelski (IPAC/Caltech), A. Koekemoer (STScI), R. Windhorst (Arizona State University), and Z. Levay (STScI)

As they indicate in their paper, the targets of their study were all nearby core-collapse supernovae (SNe) that Hubble imaged at high spatial resolutions. The images were part of the Hubble Snapshot program, created by the Space Telescope Science Institute (STScI) to provide a large sample of images for various targets. Every target is observed in a single orbit of Hubble around the Earth between other observation programs, allowing a degree of flexibility that is not possible with other observatories.

For their study, Van Dyk and his colleagues examined images of six extragalactic supernovae before and after they exploded – designated SN 2012A, SN 2013ej, SN 2016gkg, SN 2017eaw, SN 2018zd, and SN 2018aoq. With extragalactic targets, astronomers have difficulty knowing if the stars they identified were progenitors to the supernova, given the distance involved. As Van Dyk to Universe Today via email, the only way to be sure is to wait for the supernova to dim, then confirm that the progenitor star has disappeared:

“Since the supernova explosion is so luminous, we have to wait a number of years until it has faded enough that it is less luminous than was the progenitor. In a few of the cases we show in our paper, there is little question that the star that was there pre-explosion is now gone. In the other cases, we’re reasonably sure, but the supernova is still detectable and is just faint enough for us to infer that the progenitor has vanished. “

In a previous study, Van Dyk and several colleagues who were co-authors of this study investigated another supernova (iPTF13bvn) whose progenitor star disappeared. In this case, the research team relied on data obtained by Hubble of the SN site – as part of the Ultraviolet Ultra Deep Field (UVUDF) campaign – roughly 740 days after the star exploded. In 2013, Van Dyk led a study that used images from an earlier Snapshot program to confirm that the progenitor of SN 2011dh in the Whirlpool Galaxy (Messier 51) had disappeared.

The Whirlpool Galaxy (Spiral Galaxy M51, NGC 5194), a classic spiral galaxy located in the Canes Venatici constellation, and its companion NGC 5195. Credit: NASA/ESA

These and other papers over the years have shown that progenitor candidates can be directly identified from pre-explosion images. In this most recent study, Van Dyk and his colleagues observed supernovae in the later stages of their evolution to learn what mechanisms are powering them. In many cases, the mechanism is the decay of radioactive nuclei (in particular, radioactive nickel, cobalt, and iron) that were synthesized by the enormous energy of the explosion. But as he explained, they suspected that other mechanisms might be involved:

“However, we have indications that some supernovae inevitably have additional power sources — one possibility is that the light of the supernova has been scattered by interstellar dust immediate to the explosion, in the form of a ‘light echo’; another more likely possibility is that the shockwave associated with the explosion is interacting with gas that was deposited around the progenitor star by the star itself during the course of the star’s life, in the form of wind or outburst, that is, circumstellar matter. The ejecta from the explosion moving through and interacting with this circumstellar matter can result in luminous energy that can persist for years, even for decades.”

In short, the team was trying to estimate how many of the supernovae they observed evolved through radioactive decay versus more exotic powering mechanisms. Their results showed that SN 2012A, SN 2018zd, and SN 2018aoq had faded to the point where they were no longer detectable in the Hubble Snapshot images, whereas SN 2013ej, SN 2016gkg, and SN 2017eaw had faded just enough. Therefore, they could infer in all six cases that the progenitors had disappeared. However, not all were the result of a single massive star undergoing core collapse.

In the case of SN 2016gkg, the images acquired by Hubble’s Wide Field Camera 3 (WFC3) were of much higher spatial resolution and sensitivity than the images of the host galaxy, previously taken by the now-retired WFC2. This allowed them to theorize that SN 2016gkg was not the result of a single core-collapse supernova but a progenitor star interacting with a neighboring star. Said Van Dyk:

“So, in the old image, the progenitor looked like one “star,” whereas in the new images, we could see that the progenitor had to have been spatially distinct from the neighboring star. Therefore, we were able to obtain a better estimate of the progenitor’s luminosity and color, now uncontaminated by the neighbor, and from that, we were able to make some new inferences about the overall properties of the progenitor, or, in this case, progenitor system, since we characterized the new results using existing models of binary star systems.”

Artist’s impression of a supernova remnant. Credit: ESA/Hubble

Specifically, they determined that the progenitor belonged to the class of “stripped-envelope” supernovae (SESNe), in which the outer hydrogen H-rich envelope of the progenitor star has been significantly or entirely removed. They further estimated that the progenitor was the primary and its companion was likely a main sequence star. They even placed constraints on their respective masses before the explosion (4.6 and 17–20.5 solar masses, respectively).

After consulting images taken around the same time by another Snapshot program, they also noticed something interesting about SN 2017eaw. These images indicated that this supernova was especially luminous in the UV band (an “ultraviolet excess”). By combining these images with their data, Va Dyk and his team speculated that SN 2017eaw had an excess of light in the UV at the time it was observed, which was likely caused by interaction between the supernova shock and the circumstellar medium around that progenitor.

The team also noted that the dust created by a supernova explosion is a complicating factor due to how it cools as it expands outward. This dust, said Van Dyk, can obscure light from distant sources and lead to complications with the observations:

“The caveat here, then, is that the star that we saw pre-explosion might not be the progenitor at all, for instance and — again, because of the distances to the host galaxies — that star is within fractions of a pixel of the actual progenitor (physically, in the immediate neighborhood of the progenitor), such that, if the supernova has made dust, that dust is effectively blanketing both the supernova and that neighboring star. This is possible, but not inordinately likely. And it becomes a harder argument to make in those few cases where nothing is seen at the supernova position years later — as we point out in the paper, that would require enormous amounts of dust, which is likely physically not possible.”

Tracing the origins of supernovae is one of the many ways astronomers can learn more about the life cycle of stars. With improved instruments, data collection, and flexibility, they are able to reveal more about how our Universe evolved and will continue to change over time.

Further Reading: arXiv

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