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NASA's new space telescope reaches destination in solar orbit

Publish: 09:11 AM, 25 Jan, 2022


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NASA's James Webb Space Telescope, designed to give the world an unprecedented glimpse of infant galaxies in the early stages of the universe, arrived at its gravitational parking spot in orbit around the sun on Monday, nearly a million miles from Earth.

With a final five-minute, course-correcting thrust of its onboard rocket, Webb reached its destination at a position of gravitational equilibrium known as the second Sun-Earth Lagrange point, or L2, arriving one month after launch, NASA officials said.

The thruster was activated by mission control engineers at the Space Telescope Science Institute in Baltimore, with radio signals confirming Webb was successfully "inserted" into its desired orbital loop around L2.

From there, Webb will follow a special "halo" path that keeps it in constant alignment with Earth but out of its shadow, as the planet and telescope circle the sun in tandem. The prescribed L2 orbit within the larger solar orbit thus enables uninterrupted radio contact, while bathing Webb's solar-power array in non-stop sunlight.

By comparison, Webb's 30-year-old predecessor, the Hubble Space Telescope, orbits the Earth from 340 miles (547 km) away, passing in and out of the planet's shadow every 90 minutes.

The combined pull of the sun and Earth at L2 - a point of near gravitational stability first deduced by 18-century mathematician Joseph-Louis Legrange - will minimize the telescope's drift in space.

But ground teams will need to fire Webb's thruster briefly again about once every three weeks to keep it on track, Keith Parrish, the observatory's commissioning manager from NASA's Goddard Space Flight Center in Maryland, told reporters on Monday.

Mission engineers are preparing next to fine-tune the telescope's primary mirror - an array of 18 hexagonal segments of gold-coated beryllium metal measuring 21 feet, 4 inches (6.5 meters) across, far larger than Hubble's main mirror.

Its size and design - operating mainly in the infrared spectrum - will allow Webb to peer through clouds of gas and dust and observe objects at greater distances, thus farther back in time, than Hubble or any other telescope.

These features are expected to usher in a revolution in astronomy, giving a first view of infant galaxies dating to just 100 million years after the Big Bang, the theoretical flashpoint that set the expansion of the known universe in motion an estimated 13.8 billion years ago.

Webb's instruments also make it ideal to search for signs of potentially life-supporting atmospheres around scores of newly documented exoplanets - celestial bodies orbiting distant stars - and to observe worlds much closer to home, such as Mars and Saturn's icy moon Titan.

 

NEXT STEPS

It will take several more months of work to ready the telescope for its astronomical debut.

The 18 segments of its principal mirror, which had been folded together to fit inside the cargo bay of the rocket that carried the telescope to space, were unfurled with the rest of its structural components during a two-week period following Webb's launch on Dec. 25.

Those segments were recently detached from fasteners and edged away from their original launch position. They now must be precisely aligned - to within one-ten-thousandth the thickness of a human hair - to form a single, unbroken light-collecting surface.

Ground teams will also start activating Webb's various imaging and spectrographic instruments to be used in the three-month mirror alignment. This will be followed by two months spent calibrating the instruments themselves.

Mirror alignment will begin by aiming the telescope at a rather ordinary, isolated star, dubbed HD-84406, located in the Ursa Major, or "Big Dipper," constellation but too faint to be seen from Earth with the naked eye.

Engineers will then gradually tune Webb's mirror segments to "stack" 18 separate reflections of the star into a single, focused image, Lee Feinberg, Webb's optical telescope element manager at Goddard, said during Monday's NASA teleconference.

Alignment is expected to start next week when the telescope, whose infrared design makes it super-sensitive to heat, has cooled down enough in space to work properly - a temperature of about 400 degrees below zero Fahrenheit (-240 Celsius).

If all goes smoothly, Webb should be ready to begin making scientific observations by summer.

Sometime in June, NASA expects to make public its "early release observations," a 'greatest hits' collection of initial images used to demonstrate proper functioning of Webb's instruments during its commissioning phase.

Webb's most ambitious work, including plans to train its mirror on objects farthest from Earth, will take a bit longer to conduct.

The telescope is an international collaboration led by NASA in partnership with the European and Canadian space agencies. Northrop Grumman Corp was the primary contractor.


Webb Telescope   NASA  


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Three, two, one: astronomers predict SpaceX space junk will hit the Moon

Publish: 10:06 AM, 27 Jan, 2022


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A chunk of a SpaceX rocket that blasted off seven years ago and was abandoned in space after completing its mission will crash into the Moon in March, experts say.

The rocket was deployed in 2015 to put into orbit a NASA satellite called the Deep Space Climate Observatory (DSCOVR).

Since then, the second stage of the rocket, or booster, has been floating in what mathematicians call a chaotic orbit, astronomer Bill Gray told Wednesday.

It was Gray who calculated the space junk's new collision course with the Moon.

The booster passed quite close to the Moon in January in a rendezvous that altered its orbit, said Gray.

He is behind Project Pluto, software that allows for calculating the trajectory of asteroids and other objects in space and is used in NASA-financed space observation programs.

 A week after the rocket stage whizzed close to the Moon, Gray observed it again and concluded it would crash into the Moon's dark side on March 4 at more than 5,500 miles per hour (9,000 kilometers per hour).

 Gray appealed to the amateur astronomer community to join him in observing the booster, and his conclusion was confirmed.

 The exact time and spot of impact may change slightly from his forecast but there is widespread agreement that there will be a collision on the Moon that day.

 "I've been tracking junk of this sort for about 15 years. And this is the first unintentional lunar impact that we've had," Gray told.

 

- 'Time to start regulating' -

 Astronomer Jonathan McDowell told that it's possible similar impacts have taken place unnoticed. "There're at least 50 objects that were left in deep Earth orbit in the '60s, '70s and '80s that were just abandoned there. We didn't track them," he said.

 "Now we're picking up a couple of them... but a lot of them we're not finding and so they're not there anymore," he added. "Probably at least a few of them hit the moon accidentally and we just didn't notice."

 The impact of the SpaceX rocket chunk weighing four tons on the Moon will not be visible from Earth in real time.

 But it will leave a crater that scientists will be able to observe with spacecraft and satellites like NASA's Lunar Reconnaissance Orbiter or India's Chandrayaan-2, and thus learn more about the geology of the Moon.

 Spacecraft have been intentionally crashed into the Moon before for scientific purposes, such as during the Apollo missions to test seismometers.

  In 2009, NASA sent a rocket stage hurling into the Moon near its south pole to look for water.

But most rockets do not go so far from Earth. SpaceX brings its rocket boosters back through the Earth's atmosphere so they disintegrate over the ocean. The first stage is recovered and reused.

 Gray said there could be more unintentional crashes into the Moon in the future as the US and Chinese space programs in particular leave more junk in orbit.

 The US together with international partners is already planning a space station to orbit the Moon.

 McDowell noted these events "start to be problematic when there's a lot more traffic."

"It's actually no one's job to keep track of the junk that we leave out in deep earth orbit," he added. "I think now's the time to start regulating it."

Elon Musk's company is currently developing a lunar lander that should allow NASA to send astronauts back to the Moon by 2025 at the earliest.


SpaceX   Space junk  


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NASA begins process of bringing new space telescope into focus

Publish: 11:48 AM, 13 Jan, 2022


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NASA on Wednesday embarked on a months-long, painstaking process of bringing its newly launched James Webb Space Telescope into focus, a task due for completion in time for the revolutionary eye in the sky to begin peering into the cosmos by early summer.

Mission control engineers at NASA's Goddard Space Flight Center in Greenbelt, Maryland, began by sending their initial commands to tiny motors called actuators that slowly position and fine-tune the telescope's principal mirror.

Consisting of 18 hexagonal segments of gold-plated beryllium metal, the primary mirror measures 21 feet 4 inches (6.5 m) in diameter - a much larger light-collecting surface than Webb's predecessor, the 30-year-old Hubble Space Telescope.

The 18 segments, which had been folded together to fit inside the cargo bay of the rocket that carried the telescope to space, were unfurled with the rest of its structural components during a two-week period following Webb's launch on Dec. 25.

Those segments must now be detached from fasteners that held them in place for the launch and then moved forward half an inch from their original configuration - a 10-day process - before they can be aligned to form a single, unbroken, light-collecting surface.

The alignment will take an additional three months, Lee Feinberg, the Webb optical telescope element manager at Goddard, told Reuters by telephone.

Aligning the primary mirror segments to form one large mirror means each segment "is aligned to one-five-thousandth the thickness of a human hair", Feinberg said.

"All of this required us to invent things that had never been done before," such as the actuators, which were built to move incrementally at -400 Fahrenheit (-240 Celsius) in the vacuum of space, he added.

The telescope's smaller, secondary mirror, designed to direct light collected from the primary lens into Webb's camera and other instruments, must also be aligned to operate as part of a cohesive optical system.

If all goes as planned, the telescope should be ready to capture its first science images in May, which would be processed over about another month before they can be released to the public, Feinberg said.

The $9-billion telescope, described by NASA as the premier space-science observatory of the next decade, will mainly view the cosmos in the infrared spectrum, allowing it to gaze through clouds of gas and dust where stars are being born. Hubble has operated primarily at optical and ultraviolet wavelengths.

Webb is about 100 times more powerful than Hubble, enabling it to observe objects at greater distances, thus farther back in time, than Hubble or any other telescope.

 Astronomers say this will bring into view a glimpse of the cosmos never previously seen - dating to just 100 million years after the Big Bang, the theoretical flashpoint that set in motion the expansion of the observable universe an estimated 13.8 billion years ago.

 The telescope is an international collaboration led by NASA in partnership with the European and Canadian space agencies. Northrop Grumman Corp (NOC.N) was the primary contractor.


NASA   James Webb Telescope   Space mission  


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US man recovering after 'breakthrough' pig-heart transplant

Publish: 10:13 AM, 11 Jan, 2022


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A US man with terminal heart disease was implanted with a genetically modified pig heart in a first-of-its-kind surgery, and three days later the patient is doing well, his doctors reported on Monday.

The surgery, performed by a team at the University of Maryland Medicine, is among the first to demonstrate the feasibility of a pig-to-human heart transplant, a field made possible by new gene editing tools.

If proven successful, scientists hope pig organs could help alleviate shortages of donor organs.

“This was a breakthrough surgery and brings us one step closer to solving the organ shortage crisis. There are simply not enough donor human hearts available to meet the long list of potential recipients,” Dr. Bartley Griffith, who surgically transplanted the pig heart into the patient, said in a statement.

“We are proceeding cautiously, but we are also optimistic that this first-in-the-world surgery will provide an important new option for patients in the future,” Griffith added.

For 57-year-old David Bennett of Maryland, the heart transplant was his last option.

"It was either die or do this transplant. I want to live. I know it’s a shot in the dark, but it’s my last choice,” Bennett said a day before his surgery, according to a statement released by the university.

To move ahead with the experimental surgery, the university obtained an emergency authorization from the US Food and Drug Administration on New Year's Eve through its compassionate use program.

"The FDA used our data and data on the experimental pig to authorize the transplant in an end-stage heart disease patient who had no other treatment options,” said Dr. Muhammad Mohiuddin, who heads the University's program on xenotransplantation - transplanting animal organs into humans.

About 110,000 Americans are currently waiting for an organ transplant, and more than 6,000 patients die each year before getting one, according to organdonor.gov.

Bennett's genetically modified pig heart was provided by Revivicor, a regenerative medicine company based in Blacksburg, Virginia. On the morning of the surgery, the transplant team removed the pig's heart and placed it into a special device to preserve its function until the surgery.

Pigs have long been a tantalizing source of potential transplants because their organs are so similar to humans. A hog heart at the time of slaughter, for example, is about the size of an adult human heart.

Other organs from pigs being researched for transplantation into humans include kidneys, liver and lungs.

Prior efforts at pig-to-human transplants have failed because of genetic differences that caused organ rejection or viruses that posed an infection risk.

Scientists have tackled that problem by editing away potentially harmful genes.

In the heart implanted in Bennett, three genes previously linked with organ rejection were "knocked out" of the donor pig, and six human genes linked with immune acceptance were inserted into the pig genome.

Researchers also deleted a pig gene to prevent excessive growth of the pig heart tissue.

The work was funded in part with a $15.7 million research grant to evaluate Revivicor's genetically-modified pig hearts in baboon studies.

In addition to the genetic changes to the pig heart, Bennett received an experimental anti-rejection drug made by Kiniksa Pharmaceuticals based in Lexington, Mass.


US   Organ transplant  


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Discovery of UK's largest sea dragon among 'greatest' finds

Publish: 03:32 PM, 10 Jan, 2022


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Scientists have hailed one of the "greatest finds" in British paleontological history after the largest fossilised remains of a prehistoric "sea dragon" were discovered in the Midlands.

The ichthyosaur, approximately 180 million years old with a skeleton measuring around 10 metres in length and a skull weighing approximately one ton, is the largest and most complete fossil of its kind ever found in the UK.

It was discovered by Joe Davis of Leicestershire and Rutland Wildlife Trust during a routine draining of a lagoon island at Rutland Water in February 2021.

The first ichthyosaurs, which are called sea dragons because they tend to have very large teeth and eyes, were discovered by fossil hunter and paleontologist Mary Anning in the early 19th century.

Dr. Dean Lomax, a paleontologist who has studied the species, said: "Despite the many ichthyosaur fossils found in Britain, it is remarkable to think that the Rutland ichthyosaur is the largest skeleton ever found in the UK.

"It is a truly unprecedented discovery and one of the greatest finds in British paleontological history."

Ichthyosaurs, which were marine reptiles, first appeared around 250 million years ago and went extinct 90 million years ago, varying in size from one to more than 25 metres in length and resembling dolphins in general body shape.

The remains were dug out by a team of expert paleontologists from around the UK in August and September.

Two incomplete and much smaller ichthyosaurs were found during the initial construction of Rutland Water in the 1970s. However, the latest discovery is the first complete skeleton.

Dr. Mark Evans of the British Antarctic Survey said: "I've been studying the Jurassic fossil reptiles of Rutland and Leicestershire for over 20 years.

"When I first saw the initial exposure of the specimen with Joe Davis, I could tell that it was the largest ichthyosaur known from either county.

"However, it was only after our exploratory dig that we realised that it was practically complete to the tip of the tail."

He added: "It's a highly significant discovery both nationally and internationally but also of huge importance to the people of Rutland and the surrounding area."

Nigel Larkin, a specialist paleontological conservator, said: "It's not often you are responsible for safely lifting a very important but very fragile fossil weighing that much.

"It is a responsibility, but I love a challenge. It was a very complex operation to uncover, record, and collect this important specimen safely."


United Kingdom   Sea Dragon Fossil   paleontology  


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Webb telescope fully deployed in space: NASA

Publish: 10:32 AM, 09 Jan, 2022


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The James Webb Space Telescope has completed its two-week-long deployment phase, unfolding its huge, gold-plated, flower-shaped mirror panel as it readies to study every phase of cosmic history.

Engineering teams cheered back at the Space Telescope Science Institute in Baltimore, Maryland as NASA announced on Twitter that the final portion of the 6.5-meter (21-foot) mirror was deployed.

“I’m emotional about it – what an amazing milestone,” Thomas Zurbuchen, a senior NASA engineer, said during the live video feed on Saturday as stargazers worldwide celebrated.

“We see that beautiful pattern out there in the sky now.”

More powerful than the Hubble Space Telescope, the $10bn Webb will scan the cosmos for light streaming from the first stars and galaxies formed 13.7 billion years ago. To accomplish this, NASA had to outfit Webb with the biggest and most sensitive mirror ever launched – its “golden eye”, as scientists call it.

Because the telescope was too large to fit into a rocket’s nose cone in its operational configuration, it was transported folded-up.

Unfurling has been a complex and challenging task – the most daunting such project ever attempted, according to NASA.

In this photo released by NASA, James Webb Space Telescope Project Manager Bill Ochs, left, and Commissioning Manager John Durning, right, celebrate [Bill Ingalls/NASA via AFP]

The Webb blasted off in an Ariane 5 rocket from French Guiana on December 25, and is heading to its orbital point, 1.5 million km (1 million miles) from Earth.

Though Webb will reach its space destination, known as the second Lagrange point, in a matter of weeks, it still has about another five and a half months of setup to go.

The next steps include aligning the telescope’s optics, and calibrating its scientific instruments.


Webb telescope   NASA   Science  


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