Tag Archives: stars

Webb offers never-before-seen details of early universe, distant galaxy MACS0647-JD

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NASA’s James Webb Space Telescope was specially designed to detect the faint infrared light from very distant galaxies and give astronomers a glimpse at the early universe. The nature of galaxies during this early period of our universe is not well known nor understood. But with the help of gravitational lensing by a cluster of galaxies in the foreground, faint background galaxies can be magnified and also appear multiple times in different parts of the image.

Today, we sit down with three astronomers working on Webb to talk about their latest findings. The team members are Dan Coe of AURA/STScI for the European Space Agency and the Johns Hopkins University; Tiger Hsiao of the Johns Hopkins University; and Rebecca Larson of the University of Texas at Austin. These scientists have been observing the distant galaxy MACS0647-JD with Webb, and they’ve found something interesting.

The massive gravity of galaxy cluster MACS0647

Dan Coe: I discovered this galaxy MACS0647-JD 10 years ago with the Hubble Space Telescope. At the time, I’d never worked on high redshift galaxies, and then I found this one that was potentially the most distant at redshift 11, about 97 percent of the way back to the big bang. With Hubble, it was just this pale, red dot. We could tell it was really small, just a tiny galaxy in the first 400 million years of the universe. Now we look with Webb, and we’re able to resolve TWO objects! We’re actively discussing whether these are two galaxies or two clumps of stars within a galaxy. We don’t know, but these are the questions that Webb is designed to help us answer.

Tiger Yu-Yang Hsiao: You can also see that the colors between the two objects are so different. One’s bluer; the other one is redder. The blue gas and the red gas have different characteristics. The blue one actually has very young star formation and almost no dust, but the small, red object has more dust inside, and is older. And their stellar masses are also probably different.

It’s really interesting that we see two structures in such a small system. We might be witnessing a galaxy merger in the very early universe. If this is the most distant merger, I will be really ecstatic!

Dan Coe: Due to the gravitational lensing of the massive galaxy cluster MACS0647, it’s lensed into three images: JD1, JD2, and JD3. They’re magnified by factors of eight, five, and two, respectively.

Rebecca Larson: Up to this point, we haven’t really been able to study galaxies in the early universe in great detail. We had only tens of them prior to Webb. Studying them can help us understand how they evolved into the ones like the galaxy we live in today. And also, how the universe evolved throughout time.

The U.S. Postal Service will issue a stamp highlighting NASA’s James Webb Space Telescope on Sept. 8, 2022. U.S. Postal Service Art Director Derry Noyes designed the stamp using existing art by James Vaughan and an image provided by NASA and the Space Telescope Science Institute.
Credits: U.S. Postal Service

I think my favorite part is, for so many new Webb image we get, if you look in the background, there are all these little dots—and those are all galaxies! Every single one of them. It’s amazing the amount of information that we’re getting that we just weren’t able to see before. And this is not a deep field. This is not a long exposure. We haven’t even really tried to use this telescope to look at one spot for a long time. This is just the beginning!

The James Webb Space Telescope is the world’s largest, most powerful, and most complex space science telescope ever built. 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.

NASA: Are you in an area of Lucy then take a photograph, post it to social media

NASA: Are you in an area of Lucy then take a photograph, post it to social media

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On Oct. 16, at 7:04 a.m. EDT, NASA’s Lucy spacecraft, the first mission to the Jupiter Trojan asteroids, will skim the Earth’s atmosphere, passing a mere 220 miles (350 kilometers) above the surface. By sling-shotting past Earth on the first anniversary of its launch, Lucy will gain some of the orbital energy it needs to travel to this never-before-visited population of asteroids.

The Trojan asteroids are trapped in orbits around the Sun at the same distance as Jupiter, either far ahead of or behind the giant planet. Lucy is currently one year into a twelve-year voyage. This gravity assist will place Lucy on a new trajectory for a two-year orbit, at which time it will return to Earth for a second gravity assist. This second assist will give Lucy the energy it needs to cross the main asteroid belt, where it will observe asteroid Donaldjohanson, and then travel into the leading Trojan asteroid swarm. There, Lucy will fly past six Trojan asteroids: Eurybates and its satellite Queta, Polymele and its yet unnamed satellite, Leucus, and Orus. Lucy will then return to Earth for a third gravity assist in 2030 to re-target the spacecraft for a rendezvous with the Patroclus-Menoetius binary asteroid pair in the trailing Trojan asteroid swarm.

This illustration shows the Lucy spacecraft passing one of the Trojan Asteroids near Jupiter./CREDIT:Southwest Research Institute

For this first gravity assist, Lucy will appear to approach Earth from the direction of the Sun. While this means that observers on Earth will not be able to see Lucy in the days before the event, Lucy will be able to take images of the nearly full Earth and Moon. Mission scientists will use these images to calibrate the instruments.

Lucy’s trajectory will bring the spacecraft very close to Earth, lower even than the International Space Station, which means that Lucy will pass through a region full of earth-orbiting satellites and debris. To ensure the safety of the spacecraft, NASA developed procedures to anticipate any potential hazard and, if needed, to execute a small maneuver to avoid a collision.

“The Lucy team has prepared two different maneuvers,” says Coralie Adam, Lucy deputy navigation team chief from KinetX Aerospace in Simi Valley, California. “If the team detects that Lucy is at risk of colliding with a satellite or piece of debris, then–12 hours before the closest approach to Earth –the spacecraft will execute one of these, altering the time of closest approach by either two or four seconds. This is a small correction, but it is enough to avoid a potentially catastrophic collision.”

NASA/Photo: Nasa.gov

Lucy will be passing the Earth at such a low altitude that the team had to include the effect of atmospheric drag when designing this flyby. Lucy’s large solar arrays increase this effect.

“In the original plan, Lucy was actually going to pass about 30 miles closer to the Earth,” says Rich Burns, Lucy project manager at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “However, when it became clear that we might have to execute this flyby with one of the solar arrays unlatched, we chose to use a bit of our fuel reserves so that the spacecraft passes the Earth at a slightly higher altitude, reducing the disturbance from the atmospheric drag on the spacecraft’s solar arrays.”

At around 6:55 a.m. EDT, Lucy will first be visible to observers on the ground in Western Australia (6:55 p.m. for those observers). Lucy will quickly pass overhead, clearly visible to the naked eye for a few minutes before disappearing at 7:02 a.m. EDT as the spacecraft passes into the Earth’s shadow. Lucy will continue over the Pacific Ocean in darkness and emerge from the Earth’s shadow at 7:26 a.m. EDT. If the clouds cooperate, sky watchers in the western United States should be able to get a view of Lucy with the aid of binoculars.

“The last time we saw the spacecraft, it was being enclosed in the payload fairing in Florida,” said Hal Levison, Lucy principal investigator at the Southwest Research Institute (SwRI) Boulder, Colorado office. “It is exciting that we will be able to stand here in Colorado and see the spacecraft again. And this time Lucy will be in the sky.”

Lucy will then rapidly recede from the Earth’s vicinity, passing by the Moon and taking a few more calibration images before continuing out into interplanetary space.

“I’m especially excited by the final few images that Lucy will take of the Moon,” said John Spencer, acting deputy project scientist at SwRI. “Counting craters to understand the collisional history of the Trojan asteroids is key to the science that Lucy will carry out, and this will be the first opportunity to calibrate Lucy’s ability to detect craters by comparing it to previous observations of the Moon by other space missions.”

The public is invited to join the #WaveToLucy social media campaign by posting images of themselves waving towards the spacecraft and tagging the @NASASolarSystem account. Additionally, if you are in an area where Lucy will be visible, take a photograph of Lucy and post it to social media with the #SpotTheSpacecraft hashtag.

Instructions for observing Lucy from your location are available here.

 

NASA Awards $4 Million Through New Space Grant KIDS Opportunity

Astronomers Detect Protective Shield Defending Pair of ‘Dwarf Galaxies’ with help of FUSE, Hubble

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For billions of years, the Milky Way’s largest satellite galaxies – the Large and Small Magellanic Clouds – have followed a perilous journey. Orbiting one another as they are pulled in toward our home galaxy, they have begun to unravel, leaving behind trails of gaseous debris. And yet – to the puzzlement of astronomers – these dwarf galaxies remain intact, with ongoing vigorous star formation.

“A lot of people were struggling to explain how these streams of material could be there,” said Dhanesh Krishnarao, assistant professor at Colorado College. “If this gas was removed from these galaxies, how are they still forming stars?”

With the help of data from NASA’s Hubble Space Telescope and a retired satellite called the Far Ultraviolet Spectroscopic Explorer (FUSE), a team of astronomers led by Krishnarao has finally found the answer: the Magellanic system is surrounded by a corona, a protective shield of hot supercharged gas. This cocoons the two galaxies, preventing their gas supplies from being siphoned off by the Milky Way, and therefore allowing them to continue forming new stars.

Description of the above image:

Researchers have used spectroscopic observations of ultraviolet light from quasars to detect and map out the Magellanic Corona, a diffuse halo of hot, supercharged gas surrounding the Small and Large Magellanic Clouds. Shown here in purple, the corona stretches more than 100,000 light-years from the main mass of stars, gas, and dust that make up the Magellanic Clouds, intermingling with the hotter and more extensive corona that surrounds the Milky Way. The Magellanic Clouds, dwarf galaxies roughly 160,000 light-years from Earth, are the largest of the Milky Way’s satellites and are thought to be on their first in-falling passage around the Milky Way. This journey has begun to unravel what were once barred spirals with multiple arms into more irregular-shaped galaxies with long tails of debris. The corona is thought to act as a buffer protecting the dwarf galaxies’ vital star-forming gas from the gravitational pull of the much larger Milky Way. The detection of the Magellanic Corona was made by analyzing patterns in ultraviolet light from 28 distant background quasars. As the quasar light passes through the corona, certain wavelengths (colors) of ultraviolet light are absorbed. The quasar spectra become imprinted with the distinct signatures of carbon, oxygen, and silicon ions that make up the corona gas. Because each quasar probes a different part of the corona, the research team was also able to show that the amount of gas decreases with distance from the center of the Large Magellanic Cloud. This study used archival observations of quasars from Hubble’s Cosmic Origins Spectrograph (COS) and the Far Ultraviolet Spectroscopic Explorer (FUSE). Quasars have also been used to probe the Magellanic Stream, outflows from the Milky Way , and the halo surrounding the Andromeda Galaxy./Illustration Credits: STScI, Leah Hustak

 

This discovery, which was just published in Nature, addresses a novel aspect of galaxy evolution. “Galaxies envelope themselves in gaseous cocoons, which act as defensive shields against other galaxies,” said co-investigator Andrew Fox of the Space Telescope Science Institute in Baltimore, Maryland.

Astronomers predicted the corona’s existence several years ago. “We discovered that if we included a corona in the simulations of the Magellanic Clouds falling onto the Milky Way, we could explain the mass of extracted gas for the first time,” explained Elena D’Onghia, a co-investigator at the University of Wisconsin–Madison. “We knew that the Large Magellanic Cloud should be massive enough to have a corona.”

But although the corona stretches more than 100,000 light-years from the Magellanic clouds and covers a huge portion of the southern sky, it is effectively invisible. Mapping it out required scouring through 30 years of archived data for suitable measurements.

Researchers think that a galaxy’s corona is a remnant of the primordial cloud of gas that collapsed to form the galaxy billions of years ago. Although coronas have been seen around more distant dwarf galaxies, astronomers had never before been able to probe one in as much detail as this.

There’re lots of predictions from computer simulations about what they should look like, how they should interact over billions of years, but observationally we can’t really test most of them because dwarf galaxies are typically just too hard to detect,” said Krishnarao. Because they are right on our doorstep, the Magellanic Clouds provide an ideal opportunity to study how dwarf galaxies interact and evolve.

In search of direct evidence of the Magellanic Corona, the team combed through the Hubble and FUSE archives for ultraviolet observations of quasars located billions of light-years behind it. Quasars are the extremely bright cores of galaxies harboring massive active black holes. The team reasoned that although the corona would be too dim to see on its own, it should be visible as a sort of fog obscuring and absorbing distinct patterns of bright light from quasars in the background. Hubble observations of quasars were used in the past to map the corona surrounding the Andromeda galaxy.

By analyzing patterns in ultraviolet light from 28 quasars, the team was able to detect and characterize the material surrounding the Large Magellanic Cloud and confirm that the corona exists. As predicted, the quasar spectra are imprinted with the distinct signatures of carbon, oxygen, and silicon that make up the halo of hot plasma that surrounds the galaxy.

The ability to detect the corona required extremely detailed ultraviolet spectra. “The resolution of Hubble and FUSE were crucial for this study,” explained Krishnarao. “The corona gas is so diffuse, it’s barely even there.” In addition, it is mixed with other gases, including the streams pulled from the Magellanic Clouds and material originating in the Milky Way.

By mapping the results, the team also discovered that the amount of gas decreases with distance from the center of the Large Magellanic Cloud. “It’s a perfect telltale signature that this corona is really there,” said Krishnarao. “It really is cocooning the galaxy and protecting it.”

How can such a thin shroud of gas protect a galaxy from destruction?

“Anything that tries to pass into the galaxy has to pass through this material first, so it can absorb some of that impact,” explained Krishnarao. “In addition, the corona is the first material that can be extracted. While giving up a little bit of the corona, you’re protecting the gas that’s inside of the galaxy itself and able to form new stars.”

Artemis I Launch Update: Teams Replace Seals on Artemis I Moon Rocket, Prepare for Tanking Test

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After disconnecting the ground and rocket-side plates on the interface, called a quick disconnect, for the liquid hydrogen fuel feed line, teams have replaced the seals on the Space Launch System rocket’s core stage associated with the liquid hydrogen leak detected during the Artemis I launch attempt Sept. 3. 

Both the 8-inch line used to fill and drain liquid hydrogen from the core stage and the 4-inch bleed line used to redirect some of the propellant during tanking operations were removed and replaced this week.  

NASA’s Space Launch System (SLS) rocket is seen at Launch Pad 39B Thursday, Sept. 8, 2022, at NASA’s Kennedy Space Center in Florida as teams work to replace the seal on an interface, called the quick disconnect, between the liquid hydrogen fuel feed line on the mobile launcher and the rocket. Photo Credit: (NASA/Chad Siwik)

Coming up, technicians will reconnect the umbilical plates and perform inspections over the weekend before preparing for a tanking demonstration as soon as Saturday, Sept. 17. This demonstration will allow engineers to check the new seals under cryogenic, or supercold, conditions as expected on launch day and before proceeding to the next launch attempt.  

NASA/Photo: Nasa.gov

During the operation, teams will practice loading liquid hydrogen and liquid oxygen in the rocket’s core stage and interim cryogenic propulsion stage and getting to a stable replenish state for both propellants.

Teams will confirm the leak has been repaired and also perform the kick-start bleed test and a pre-pressurization test, which will validate the ground and flight hardware and software systems can perform the necessary functions required to thermally condition the engines for flight.  Following the test, teams will evaluate the data along with plans for the next launch opportunity. 

 Artemis I Launch Update: Repair Work Underway, Preparations Continue for Next Launch

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Engineers are making progress repairing the area where a liquid hydrogen leak was detected during the Artemis I launch attempt Sept. 3, and NASA is preserving options for the next launch opportunity as early as Friday, Sept. 23. 

Technicians constructed a tent-like enclosure around the work area to protect the hardware and teams from weather and other environmental conditions at Launch Pad 39B. They have disconnected the ground- and rocket-side plates on the interface, called a quick disconnect, for the liquid hydrogen fuel feed line, performed initial inspections, and began replacing two seals – one surrounding the 8-inch line used to fill and drain liquid hydrogen from the core stage, and another surrounding the 4-inch bleed line used to redirect some of the propellant during tanking operations. The SLS rocket and Orion spacecraft are in good condition while remaining at the launch pad. 

Once the work is complete, engineers will reconnect the plates and perform initial tests to evaluate the new seals. Teams will check the new seals under cryogenic, or supercold, conditions no earlier than Sept. 17 in which the rocket’s core stage and interim cryogenic propulsion stage will be loaded with liquid oxygen and liquid hydrogen to validate the repair under the conditions it would experience on launch day. Engineers are in the process of developing a full plan for the checkouts. 

Artemis I logo/NASA

NASA has submitted a request to the Eastern Range for an extension of the current testing requirement for the flight termination system. NASA is respecting the range’s processes for review of the request, and the agency continues to provide detailed information to support a range decision.  

In the meantime, NASA is instructing the Artemis team to move forward with all preparations required for testing, followed by launch, including preparations to ensure adequate supplies of propellants and gases used in tanking operations, as well as flight operations planning for the mission. NASA has requested the following launch opportunities: 

  • Sept 23: Two-hour launch window opens at 6:47 a.m. EDT; landing on Oct. 18 
  • Sept. 27: 70-minute launch window opens at 11:37 a.m.; landing on Nov. 5 

NASA’s teams internally are preparing to support additional dates in the event flexibility is required. The agency will evaluate and adjust launch opportunities and alternate dates based on progress at the pad and to align with other planned activities, including DART’s planned impact with an asteroid, the west coast launch of a government payload, and the launch of Crew-5 to the International Space Station. 

NASA/Photo: Nasa.gov

Listen to a replay of today’s media teleconference on the status of the Artemis I mission. Artemis I is an uncrewed flight test to provide a foundation for human exploration in deep space and demonstrate our commitment and capability to extend human existence to the Moon and beyond.  

NASA Awards $4 Million Through New Space Grant KIDS Opportunity

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NASA is awarding more than $4 million to institutions across the U.S. to help bring the excitement of authentic NASA experiences to groups of middle and high school students who are traditionally underserved and underrepresented in STEM.

The new Space Grant K-12 Inclusiveness and Diversity in STEM (SG KIDS) opportunity will boost these students’ sense of belonging in STEM subjects, a critical first step toward STEM degrees and careers.

SG KIDS is a pilot program made possible through NASA’s National Space Grant and Fellowship Project, which comprises Space Grant Consortia led by an institution in each of the 50 states, the District of Columbia, and Puerto Rico. This opportunity represents a new approach by asking the awarded consortia to reach beyond state boundaries to create regional projects tailored to students in those areas. Through partnerships, the awardees will be able to share these exciting STEM opportunities with students residing in other states.

sg_kids_award/Photo: NASA

“Through Space Grant KIDS, we’ve asked the nation’s Space Grant consortia to deploy educational activities across state lines to share the excitement of NASA and STEM with students who otherwise might not have that opportunity,” said Mike Kincaid, NASA’s associate administrator for the Office of STEM Engagement, which administers NASA Space Grant. “We’re looking forward to seeing how these regional partnerships will make a lasting difference for the Artemis Generation.”

SG KIDS addresses the White House Executive Order on Advancing Racial Equity and Support for Underserved Communities Through the Federal Government, as well as NASA Administrator Bill Nelson’s focus on providing authentic STEM opportunities to K-12 students.

The projects funded under SG KIDS will provide students with hands-on experiences and lessons that bring NASA’s missions to life, provide training and resources to the educators teaching those students, and boost the STEM ecosystem in these regions.

NASA/Photo: Nasa.gov

“Space Grant KIDS is designed to establish networks that deliver enriching NASA STEM experiences to underserved student populations,” said Dr. Erica Alston, NASA’s deputy Space Grant manager. “We can leverage these networks to reach traditionally overlooked groups in future DEIA efforts.”

Each of the four grantees, Virginia Space Grant Consortium, Georgia Space Grant Consortium, Ohio Space Grant Consortium and Texas Space Grant Consortium, will receive approximately $1,050,000 in cooperative agreements to put their proposals into action during the next three years.

NASA Hosts National Space Council Meeting, Vice President Kamala Harris Chairs Event

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Vice President Kamala Harris highlighted the importance of climate, human spaceflight, and STEM education during the Biden-Harris Administration’s second National Space Council meeting Friday, held at NASA’s Johnson Space Center in Houston.

“For generations, with our allies and partners around the globe, America has led our world in the exploration and use of space,” said Harris. “Our leadership has been guided by a set of fundamental principles – cooperation, security, ambition, and public trust – which is the recognition, of course, that space can and must be protected for the benefit of all people.

There is so much we still don’t know and so much we still haven’t done – space remains a place of undiscovered and unrealized opportunity. Our test and our responsibility is to work together to guide humanity forward into this new frontier and to make real the incredible potential of space for all people.”

National Space Council Meeting led by Chairwoman, Vice President Kamala Harris. Photo Date: September 9, 2022. Location: Building 9NW, SVMF. Photographer: Robert Markowitz.

For more than 50 years, NASA satellites have provided open-source and publicly available data on Earth’s land, water, temperature, weather, and climate. Improving access to key climate information is a priority for the agency. Building on his previous announcement, NASA Administrator Bill Nelson released the first concept, and shared a new video for the Earth Information Center. The center will allow the public to see how the Earth is changing and guide decision makers to mitigate, adapt, and respond to climate change.

“Just like we use mission control to monitor operations during spaceflight, we’re embarking on this effort to monitor conditions here on our home planet, and it will be available to everyone in an easy-to-access format,” Nelson said.

Planning for the Earth Information Center is underway with the initial phase providing an interactive visual display of imagery and data from NASA and other government agencies. NASA Headquarters plans to house this initial interactive display with goals to expand in person and virtual access over the next five years.

The Vice President also underscored the important research conducted on the International Space Station that will enable long duration stays on the Moon and future human missions to Mars, in addition to benefits to life here on Earth.

NASA/Photo: Nasa.gov

“NASA uses the International Space Station to conduct critical research on the risks associated with future Mars missions – space radiation, isolation, and distance from Earth, just to name a few. It’s also a testbed to develop the technologies we’ll need for long duration stays on the Moon, where we will build an Artemis Base Camp on the surface and Gateway outpost in lunar orbit,” Nelson said. “Research on the space station demonstrates that the benefits of microgravity are not just for discovery. We also develop new technologies that improve life on Earth, like treatments for cancer.”

In conjunction with the meeting, NASA announced a new Space Grant K-12 Inclusiveness and Diversity in STEM (SG KIDS) opportunity that will award more than $4 million to institutions across the U.S. to help bring the excitement of NASA and STEM to traditionally underserved and underrepresented groups of middle and high school students. The announcement is a part of a broader set of commitments made by public, private, and philanthropic partners announced by the Vice President to help in the recruitment and development of the next generation of the space workforce.

SG KIDS also addresses the White House Executive Order on Advancing Racial Equity and Support for Underserved Communities Through the Federal Government, as well as NASA Administrator Bill Nelson’s focus on providing authentic STEM opportunities to K-12 students.

While at NASA’s Johnson Space Center, Vice President Harris toured the agency’s mission control with Nelson and Johnson Center Director Vanessa Wyche. The Vice President also spoke with NASA astronauts Bob Hines, Kjell Lindgren, and Jessica Watkins, living and working aboard the International Space Station about how their research benefits life on Earth, supports long duration space flight, and protects our planet.

The Vice President also received a tour of the Space Vehicle Mockup Facility (SVMF), where space flight crews and their support personnel receive world class training on high-fidelity hardware for real-time mission support. The SVMF consists of space station, Orion, Commercial vehicle mockups, part-task trainers and rack interfaces, a Precision Air Bearing Floor, and a Partial Gravity Simulator.

A recording of the full National Space Council meeting is available online at:

https://go.nasa.gov/3eEGxEW

NASA’s Hubble finds spiraling stars ‘NGC 346’, providing window into early universe

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Nature likes spirals – from the whirlpool of a hurricane, to pinwheel-shaped protoplanetary disks around newborn stars, to the vast realms of spiral galaxies across our universe.

Now astronomers are bemused to find young stars that are spiraling into the center of a massive cluster of stars in the Small Magellanic Cloud, a satellite galaxy of the Milky Way.

The outer arm of the spiral in this huge, oddly shaped stellar nursery called NGC 346 may be feeding star formation in a river-like motion of gas and stars. This is an efficient way to fuel star birth, researchers say.

The Small Magellanic Cloud has a simpler chemical composition than the Milky Way, making it similar to the galaxies found in the younger universe, when heavier elements were more scarce. Because of this, the stars in the Small Magellanic Cloud burn hotter and so run out of their fuel faster than in our Milky Way.

Though a proxy for the early universe, at 200,000 light-years away the Small Magellanic Cloud is also one of our closest galactic neighbors.

The massive star cluster NGC 346, located in the Small Magellanic Cloud, has long intrigued astronomers with its unusual shape. This shape is partly due to stars and gas spiraling into the center of this cluster in a river-like motion.
ILLUSTRATION: NASA, ESA, Andi James (STScI)

Learning how stars form in the Small Magellanic Cloud offers a new twist on how a firestorm of star birth may have occurred early in the universe’s history, when it was undergoing a “baby boom” about 2 to 3 billion years after the big bang (the universe is now 13.8 billion years old).

The new results find that the process of star formation there is similar to that in our own Milky Way.

Only 150 light-years in diameter, NGC 346 boasts the mass of 50,000 Suns. Its intriguing shape and rapid star formation rate has puzzled astronomers. It took the combined power of NASA’s Hubble Space Telescope and the European Southern Observatory’s Very Large Telescope (VLT) to unravel the behavior of this mysterious-looking stellar nesting ground.

“Stars are the machines that sculpt the universe. We would not have life without stars, and yet we don’t fully understand how they form,” explained study leader Elena Sabbi of the Space Telescope Science Institute in Baltimore. “We have several models that make predictions, and some of these predictions are contradictory. We want to determine what is regulating the process of star formation, because these are the laws that we need to also understand what we see in the early universe.”

Researchers determined the motion of the stars in NGC 346 in two different ways. Using Hubble, Sabbi and her team measured the changes of the stars’ positions over 11 years. The stars in this region are moving at an average velocity of 2,000 miles per hour, which means that in 11 years they move 200 million miles. This is about 2 times the distance between the Sun and the Earth.

Tarantula Nebula star-forming region in a new light, including tens of thousands of never-before-seen young stars that were previously shrouded in cosmic dust./Photo:NASA, ESA, CSA, STScI, Webb ERO Production Team

But this cluster is relatively far away, inside a neighboring galaxy. This means the amount of observed motion is very small and therefore difficult to measure. These extraordinarily precise observations were possible only because of Hubble’s exquisite resolution and high sensitivity. Also, Hubble’s three-decade-long history of observations provides a baseline for astronomers to follow minute celestial motions over time.

The second team, led by Peter Zeidler of AURA/STScI for the European Space Agency, used the ground-based VLT’s Multi Unit Spectroscopic Explorer (MUSE) instrument to measure radial velocity, which determines whether an object is approaching or receding from an observer.

“What was really amazing is that we used two completely different methods with different facilities and basically came to the same conclusion, independent of each other,” said Zeidler. “With Hubble, you can see the stars, but with MUSE we can also see the gas motion in the third dimension, and it confirms the theory that everything is spiraling inwards.”

But why a spiral?

“A spiral is really the good, natural way to feed star formation from the outside toward the center of the cluster,” explained Zeidler. “It’s the most efficient way that stars and gas fueling more star formation can move towards the center.”

Half of the Hubble data for this study of NGC 346 is archival. The first observations were taken 11 years ago. They were recently repeated to trace the motion of the stars over time. Given the telescope’s longevity, the Hubble data archive now contains more than 32 years of astronomical data powering unprecedented, long-term studies.

“The Hubble archive is really a gold mine,” said Sabbi. “There are so many interesting star-forming regions that Hubble has observed over the years. Given that Hubble is performing so well, we can actually repeat these observations. This can really advance our understanding of star formation.”

Observations with NASA’s James Webb Space Telescope should be able to resolve lower-mass stars in the cluster, giving a more holistic view of the region. Over Webb’s lifespan, astronomers will be able to repeat this experiment and measure the motion of the low-mass stars. They could then compare the high-mass stars and the low-mass stars to finally learn the full extent of the dynamics of this nursery.

The Hubble Space Telescope is a project of international cooperation between NASA and ESA. NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy, in Washington, D.C.

US Postal Service Celebrates NASA’s Webb Telescope With New Postal Stamp

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The U.S. Postal Service will issue a stamp celebrating NASA’s new James Webb Space Telescope, the largest, most powerful, and most complex science telescope ever put in space. The stamp, which features an illustration of the observatory, will be dedicated in a ceremony Thursday, Sept. 8, at the Smithsonian’s National Postal Museum in Washington.

“When anyone who uses these stamps looks at this telescope, I want them to see what I see: its incredible potential to reveal new and unexpected discoveries that help us understand the origins of the universe, and our place in it,” said NASA Associate Administrator Bob Cabana. “This telescope is the largest international space science program in U.S. history, and I can’t wait to see the scientific breakthroughs it will enable in astronomy.”

Webb, a mission led by NASA in partnership with ESA (European Space Agency) and CSA (Canadian Space Agency), launched Dec. 25, 2021, from Europe’s Spaceport in French Guiana. Over the following months, Webb traveled to its destination nearly one million miles (1.5 million kilometers) away from Earth, underwent weeks of complex deployments to unfold into its final configuration, and prepared its mirrors and science instruments to capture never-before-seen views of the universe.

The U.S. Postal Service will issue a stamp highlighting NASA’s James Webb Space Telescope on Sept. 8, 2022. U.S. Postal Service Art Director Derry Noyes designed the stamp using existing art by James Vaughan and an image provided by NASA and the Space Telescope Science Institute.
Credits: U.S. Postal Service

NASA released Webb’s first full-color images and spectra July 12 – providing a first look at the observatory’s powerful capabilities. The U.S. Postal Service stamp honors these achievements as Webb continues its mission to explore the unknown in our universe and study every phase in cosmic history.

“I am excited to add this beautiful stamp to our collection, as we watch from the ground as humanity’s newest and most capable telescope unlocks the greatest secrets of our cosmos that have been waiting to be revealed since the beginning of time,” said Thomas Zurbuchen, associate administrator for NASA’s Science Mission Directorate. “The Webb Telescope represents the start to a new era of what we can accomplish for the benefit of all.”

The stamp features an artist’s digital illustration of Webb against a background of stars. The selvage around each set of stamps showcases a sharp image of a star, captured while setting up the telescope in space to confirm precise alignment of Webb’s 18 hexagonal mirror segments.

The U.S. Postal Service’s first day of issue event is free and open to the public on Thursday, Sept. 8, at 11 a.m. EDT at the National Postal Museum. NASA Associate Administrator Bob Cabana; Lee Feinberg, Webb optical telescope element manager at NASA’s Goddard Space Flight Center; and Erin Smith, Webb deputy observatory project scientist at NASA Goddard will be among the speakers providing remarks.

NASA/Photo: Nasa.gov

To follow along with NASA’s Webb Telescope as it begins its mission to unfold the infrared universe, visit:

https://www.nasa.gov/webb

The James Webb Space Telescope is the world’s premier infrared 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).

NASA hopes to Launch Artemis I Moon Mission on Sept 3

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NASA will target Saturday, Sept. 3 at 2:17 p.m. EDT, the beginning of a two-hour window, for the launch of Artemis I, the first integrated test of NASA’s Orion spacecraft, Space Launch System (SLS) rocket, and the ground systems at the agency’s Kennedy Space Center in Florida.

Mission managers met Tuesday to discuss data and develop a forward plan to address issues that arose during an Aug. 29 launch attempt for the flight test. During that launch attempt, teams were not able to chill down the four RS-25 engines to approximately minus 420 degrees F, with engine 3 showing higher temperatures than the other engines. Teams also saw a hydrogen leak on a component of the tail service mast umbilical quick disconnect, called the purge can, and managed the leak by manually adjusting propellant flow rates.

Artemis I launch on Aug 27, 2022 / NASA

In the coming days, teams will modify and practice propellant loading procedures to follow a procedure similar to what was successfully performed during the Green Run at NASA’s Stennis Space Center in Mississippi. The updated procedures would perform the chilldown test of the engines, also called the kick start bleed test, about 30 to 45 minutes earlier in the countdown during the liquid hydrogen fast fill liquid phase for the core stage.

Teams also are configuring platforms at Launch Pad 39B to enable engineers access to the purge can on the tail service mast umbilical. Once access is established, technicians will perform assessments and torque connection points where necessary.

Meteorologists with the U.S. Space Force Space Launch Delta 45 predict favorable weather conditions for Saturday. While rain showers are expected, they are predicted to be sporadic during the launch window.

The mission management team will reconvene Thursday to review data and overall readiness.

Sharpest image ever of universe’s most massive known star

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By harnessing the capabilities of the 8.1-meter Gemini South telescope in Chile, which is part of the International Gemini Observatory operated by NSF’s NOIRLab, astronomers have obtained the sharpest image ever of the star R136a1, the most massive known star in the Universe. Their research, led by NOIRLab astronomer Venu M. Kalari, challenges our understanding of the most massive stars and suggests that they may not be as massive as previously thought.

Astronomers have yet to fully understand how the most massive stars — those more than 100 times the mass of the Sun — are formed. One particularly challenging piece of this puzzle is obtaining observations of these giants, which typically dwell in the densely populated hearts of dust-shrouded star clusters. Giant stars also live fast and die young, burning through their fuel reserves in only a few million years. In comparison, our Sun is less than halfway through its 10 billion year lifespan. The combination of densely packed stars, relatively short lifetimes, and vast astronomical distances makes distinguishing individual massive stars in clusters a daunting technical challenge.

By pushing the capabilities of the Zorro instrument on the Gemini South telescope of the International Gemini Observatory, operated by NSF’s NOIRLab, astronomers have obtained the sharpest-ever image of R136a1 — the most massive known star. This colossal star is a member of the R136 star cluster, which lies about 160,000 light-years from Earth in the center of the Tarantula Nebula in the Large Magellanic Cloud, a dwarf companion galaxy of the Milky Way.

Previous observations suggested that R136a1 had a mass somewhere between 250 to 320 times the mass of the Sun. The new Zorro observations, however, indicate that this giant star may be only 170 to 230 times the mass of the Sun. Even with this lower estimate, R136a1 still qualifies as the most massive known star.

Astronomers are able to estimate a star’s mass by comparing its observed brightness and temperature with theoretical predictions. The sharper Zorro image allowed NSF’s NOIRLab astronomer Venu M. Kalari and his colleagues to more accurately separated the brightness of R136a1 from its nearby stellar companions, which led to a lower estimate of its brightness and therefore its mass.

“Our results show us that the most massive star we currently know is not as massive as we had previously thought,” explained Kalari, lead author of the paper announcing this result. “This suggests that the upper limit on stellar masses may also be smaller than previously thought.”

This result also has implications for the origin of elements heavier than helium in the Universe. These elements are created during the cataclysmicly explosive death of stars more than 150 times the mass of the Sun in events that astronomers refer to as pair-instability supernovae. If R136a1 is less massive than previously thought, the same could be true of other massive stars and consequently pair instability supernovae may be rarer than expected.

The star cluster hosting R136a1 has previously been observed by astronomers using the NASA/ESA Hubble Space Telescope and a variety of ground-based telescopes, but none of these telescopes could obtain images sharp enough to pick out all the individual stellar members of the nearby cluster.

Gemini South’s Zorro instrument was able to surpass the resolution of previous observations by using a technique known as speckle imaging, which enables ground-based telescopes to overcome much of the blurring effect of Earth’s atmosphere [1]. By taking many thousands of short-exposure images of a bright object and carefully processing the data, it is possible to cancel out almost all this blurring [2]. This approach, as well as the use of adaptive optics, can dramatically increase the resolution of ground-based telescopes, as shown by the team’s sharp new Zorro observations of R136a1 [3].

“This result shows that given the right conditions an 8.1-meter telescope pushed to its limits can rival not only the Hubble Space Telescope when it comes to angular resolution, but also the James Webb Space Telescope,” commented Ricardo Salinas, a co-author of this paper and the instrument scientist for Zorro. “This observation pushes the boundary of what is considered possible using speckle imaging.”

“We began this work as an exploratory observation to see how well Zorro could observe this type of object,” concluded Kalari. “While we urge caution when interpreting our results, our observations indicate that the most massive stars may not be as massive as once thought.”

Zorro and its twin instrument `Alopeke are identical imagers mounted on the Gemini South and Gemini North telescopes, respectively. Their names are the Hawaiian and Spanish words for “fox” and represent the telescopes’ respective locations on Maunakea in Hawai‘i and on Cerro Pachón in Chile. These instruments are part of the Gemini Observatory’s Visiting Instrument Program, which enables new science by accommodating innovative instruments and enabling exciting research. Steve B. Howell, current chair of the Gemini Observatory Board and senior research scientist at the NASA Ames Research Center in Mountain View, California, is the principal investigator on both instruments.

“Gemini South continues to enhance our understanding of the Universe, transforming astronomy as we know it. This discovery is yet another example of the scientific feats we can accomplish when we combine international collaboration, world-class infrastructure, and a stellar team,” said NSF Gemini Program Officer Martin Still.