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NASA's huge James Webb Space Telescope is one month from launch –



The long-awaited launch of NASA’s next generational observatory, the James Webb Space Telescope, is just one month away.

The $9.8 billion Webb has overcome years of technical delays, funding issues and a pandemic to get to launch day in French Guiana, which is set for no earlier than Dec. 18.

Webb will have an ambitious science agenda stretching from studying small worlds in our solar system to surveying the outer reaches of the universe. “We’re going to look at everything there is in the universe that we can see,” Webb senior project scientist John Mather told reporters in a press conference on Wednesday (Nov. 18). 

Related: Building the James Webb Space Telescope (photos)

“We want to know, How did we get here?” added Mather, who works at NASA’s Goddard Space Flight Center in Maryland. “The Big Bang, How does that work? We’ll look, yes, and we have predictions. But we don’t honestly know [how].”

Serving as the successor to NASA’s venerable Hubble Space Telescope, Webb will journey to a distant destination about 1 million miles (1.6 million kilometers) from Earth known as a Lagrange point, a gravitationally stable spot between two celestial bodies. 

It will take Webb a month to get there after launch. Then, the observatory will endure a six-month commissioning period that will include a variety of key milestones, from the unfurling of its complex mirror to ensuring that all instruments are working correctly, before Webb opens its eyes.

“At six and a half meters [21 feet], the primary mirror was too big to fit in a rocket, so we designed it so that would it would unfold in space,” Lee Feinberg, Webb optical telescope element manager at Goddard, said during today’s briefing. “It doesn’t fold like a drop leaf table, so … we needed mirrors that had to be in segments.”

The mirrors, Feinberg added, initially act like 18 separate telescopes, and it will take algorithms several months to align them properly, to a precision of one-5,000th the diameter of a human hair. And that’s assuming the telescope unfurls them all properly, which (despite years of testing and modeling) NASA has said is one of the biggest technical obstacles Webb will face.

Webb investigators are coy about what the telescope will focus on first once it’s ready. But clues come from the list of “early release science programs” that will prioritize Webb’s core science in the study of planets, the solar system, galaxies, black holes, stellar physics and star populations. 

The first images will be in high demand, as mission scientists say the resolution will be 100 times better than that of Hubble and will reveal much more in infrared (or heat) wavelengths than the elder telescope can.

While the first targets have not yet been decided upon, Webb will soon be turning the clock back on observations of the universe, providing a look at the cosmos as it was just 100 million years after the Big Bang. Hubble has allowed scientists to peer back to 400 million years after the Big Bang, so Webb will fill a gap, Mather said.

Canada is providing a fine guidance sensor for pointing Webb, along with a spectrograph for examining exoplanets and galaxies. The nation receives a guaranteed 5% share of observing time for its contribution.

“One Canadian team will focus their studies on the atmospheres of exoplanets to determine their compositions and temperatures. Another Canadian team will study some of the first galaxies ever formed and galaxies gathered in dense neighborhoods called clusters,” said Sarah Gallagher, an advisor to the Canadian Space Agency president.

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What excites scientists most is the unpredictability of what Webb will reveal, and even a brief glance at Hubble history provides plenty of examples. At Hubble’s launch in April 1990, no one knew of the existence of dark energy, a fundamental influence in cosmic expansion. Exoplanets also hadn’t been confirmed yet, and yet today we know of thousands.

Hubble even found some surprises closer to home, such as when it helped NASA’s New Horizons Pluto probe steer properly around some new discoveries. “Hubble discovered two new moons of Pluto that could help the New Horizons probe [navigate] the physics of that world a few years ago,” said Klaus Pontoppidan, Webb project scientist at the Space Telescope Science Institute in Baltimore. “We think Webb will would be no different in that sense.”

Although launch day is always expected to induce butterflies, Greg Robinson, NASA’s Webb program director, said he is confident the team will pull through to make these science discoveries a reality. 

“We test as much as possible, as practical. We call it test as you fly,” he said. “We tested the same way it’s going to operate, based on a launch. And so we’ve done all of that, and I think we’re in pretty good shape.”

Follow Elizabeth Howell on Twitter @howellspace. Follow us on Twitter @Spacedotcom and on Facebook

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A Surprisingly Large Number Of “Stars” You See In The Sky Are Actually Spacecraft – Wonderful Engineering



Thousands of communication satellites are being designed and launched at a rapid pace. These satellites will have a negative impact on observational astronomy research and are likely to significantly disrupt recreational or traditional cultural stargazing.

If you look up in the sky, you might notice a sequence of bright star-like objects moving in a straight line. Those aren’t stars. They’re Starlink satellites, and they’ll soon be even more noticeable in the dark sky.

Samantha Lawler, assistant professor of astronomy at the University of Regina, recently wrote a piece in The Conversation warning that “one out of every 15 points” of light in the sky could someday be a satellite rather than a star. Moreover, she said he also thinks that satellite companies like Elon Musk’s SpaceX’s Starlink will immensely impact space research.

“This will be devastating to research astronomy and will completely change the night sky worldwide,” she wrote.

Lawler’s forthcoming study will be published in The Astronomical Journal, which will show evidence for the adverse stargazing effects of satellite megaconstellations like SpaceX’s.

Given that firms like SpaceX offer internet to locations around the world that might otherwise be without it, Lawler believes that regulatory agencies should limit the number of visible satellites in orbit.

“Our perspective of the stars will soon be changed forever,” she added if that doesn’t happen.

“We can’t accept the global loss of access to the night sky, which we’ve been able to see and connect with for as long as we’ve been human,” she wrote.

Our orbit is clogged with space debris. Starlink’s satellites have to avoid space junk as well. Will legislators intervene to put a stop to it? If prior responses to existential concerns like climate change are any indication, it will be considered later rather than sooner.

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Dinosaur tail found in Chile stuns scientists – Phys.Org



Miniature models of the Stegouros elengassen, a species of dinosaur discovred in Patagonia in 2018, is seen on display December 1, 2021 in Santiago.

Chilean paleontologists on Wednesday presented their findings on a dinosaur discovered three years ago in Patagonia which they said had a highly unusual tail that has stumped researchers

The remains of the Stegouros elengassen were discovered during excavations in 2018 at Cerro Guido, a site known to harbor numerous fossils, by a team who believed they were dealing with an already known species of dinosaur until they examined its .

“That was the main surprise,” said Alexander Vargas, one of the paleontologists. “This structure is absolutely amazing.”

“The tail was covered with seven pairs of osteoderms … producing a weapon absolutely different from anything we know in any dinosaur,” added the researcher during a presentation of the discovery at the University of Chile.

The osteoderms—structures of bony plaques located in the dermal layers of the skin – were aligned on either side of the tail, making it resemble a large fern.

Paleontologists have discovered 80 percent of the dinosaur’s skeleton and estimate that the animal lived in the area 71 to 74.9 million years ago. It was about two meters (almost seven feet) long, weighed 150 kilograms (330 pounds) and was a herbivore.

According to the scientists, who published their research in the journal Nature, the animal could represent a hitherto unknown lineage of armored dinosaur never seen in the but already identified in the northern part of the continent.

The remains of a Stegouros elengassen, a new species of dinosaur discovered in Patagonia, is seen on display in Santiago Decembe
The remains of a Stegouros elengassen, a new species of dinosaur discovered in Patagonia, is seen on display in Santiago December 1, 20121.

“We don’t know why (the tail) evolved. We do know that within armored dinosaur groups there seems to be a tendency to independently develop different osteoderm-based defense mechanisms,” said Sergio Soto, another member of the team.

The Cerro Guido area, in the Las Chinas valley 3,000 km (1,800 miles) south of Santiago, stretches for 15 kilometers. Various rock outcrops contain numerous fossils.

The finds there allowed the scientists to surmise that present-day America and Antarctica were close to each other millions of years ago.

“There is strong evidence that there is a biogeographic link with other parts of the planet, in this case Antarctica and Australia, because we have two armored there closely related” to the Stegouros, said Soto.

Explore further

New dinosaur species from Chile had a unique slashing tail

More information:
Alexander Vargas, Bizarre tail weaponry in a transitional ankylosaur from subantarctic Chile, Nature (2021). DOI: 10.1038/s41586-021-04147-1.

© 2021 AFP

Dinosaur tail found in Chile stuns scientists (2021, December 4)
retrieved 4 December 2021

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Total solar eclipse brings darkness to Antarctic summer –



Video released by NASA shows a total solar eclipse as seen from Western Antarctica on Saturday.

The Earth’s southernmost continent experiences continual daylight from mid-October until early April, but the eclipse brought a few minutes of total darkness.

NASA said the period of totality began at 2:44 a.m. ET. 

A solar eclipse occurs when the moon moves between the sun and Earth, casting a shadow on Earth, fully or partially blocking the sun’s light in some areas.

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For a total eclipse to take place the sun, moon, and Earth must be in a direct line. The only place that this total eclipse could be seen was Antarctica.

The eclipse was also expected to be visible partially from South Africa, Chile, New Zealand and Australia on Saturday.

North America gets its next glimpse of a full solar eclipse on April 8, 2024.

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