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Originally Posted by PortlandDawg
I made this today. Those that know will know.


[Linked Image from i.imgur.com]

Love this telescope!


You know my love will Not Fade Away.........


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Webb telescope reveals unpredicted bounty of bright galaxies in early universe

https://www.science.org/content/art...utm_source=Social&utm_medium=Twitter

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The James Webb Space Telescope has only been watching the sky for a few weeks, and it has already delivered a startling finding: tens, hundreds, maybe even 1000 times more bright galaxies in the early universe than astronomers anticipated.

“No one was expecting anything like this,” says Michael Boylan-Kolchin of the University of Texas, Austin. “Galaxies are exploding out of the woodwork,” says Rachel Somerville of the Flatiron Institute.

Galaxy formation models may now need a revision, as current ones hold that gas clouds should be far slower to coalesce into stars and galaxies than is suggested by Webb’s galaxy-rich images of the early universe, less than 500 million years after the big bang. “This is way outside the box of what models were predicting,” says Garth Illingworth of the University of California (UC), Santa Cruz.

Webb, a NASA-led orbiting observatory with contributions from the European and Canadian space agencies, began observing in late June from its vantage point 1.5 million kilometers from Earth. Much of its time so far has been devoted to projects meant to show off its capabilities, such as the Cosmic Evolution Early Release Science (CEERS) Survey. Webb is designed to delve deeper into cosmic history than its predecessor, the Hubble Space Telescope. Its 6.5-meter mirror—with six times the area of Hubble’s—can catch more light from distant sources, and unlike Hubble it operates at infrared wavelengths, making Webb more sensitive to those faraway sources, whose light is stretched to longer, redder wavelengths by cosmic expansion.

Within days after Webb began observations, it spotted a candidate galaxy that appears to have been shining brightly when the universe was just 230 million years old, 1.7% of its current age, which would make it the most distant ever seen. Surveys since then have shown that object is just one of a stunning profusion of early galaxies, each small by today’s standards, but more luminous than astronomers had expected.

Some researchers caution that the abundance, based on images of a small patch of sky, may be an illusion. Boylan-Kolchin wonders whether Webb just got “extra lucky” and stared into a huge clump of galaxies, denser than the rest of the early universe. That question will be resolved when CEERS broadens its scope later this year and results come in from other wide-ranging surveys.

It is also possible that astronomers are misidentifying galaxies from slightly more recent times as very early ones. Spectra are the gold standard for gauging a galaxy’s age because they allow the reddening of its light to be measured precisely. But gathering spectra from many galaxies takes time. Instead, Webb surveys so far have estimated galaxy ages from the color they appear in images—a relatively crude method. Webb’s near-infrared camera filters their light into a few wide wavelength bins, giving astronomers a rough measurement of color; redder equals more distant. But dust surrounding a galaxy can fool observers, as it can absorb starlight and re-emit it at longer wavelengths, making the galaxy look redder.

Webb’s early science teams have already identified a few such masquerading galaxies, as they report in several recent preprints. But if the profusion of early galaxies is real, astronomers may have to fundamentally rethink galaxy formation or the reigning cosmology.

Viewing nearby galaxies, researchers have concluded that heat within gas clouds slows how quickly gravity would otherwise condense the matter into stars—making star formation take about 100 times longer than if gravity alone was in charge. As the first stars in a protogalaxy begin to shine, they inject more heat into the gas, pumping the brakes on further star formation. And the first stars are short-lived giants; when they explode as supernovae they heat up gas clouds even more or blast them out of a forming galaxy completely.

Studies with Hubble have shown that the rate of star formation has been relatively constant as far back as about 600 million years after the big bang, says Charlotte Mason of the Niels Bohr Institute. But the Webb results imply that at earlier times its pace was much more rapid—as fast, Somerville suggests, as if gas clouds were collapsing freely, without any braking from heat or supernovae.

Indeed, Tommaso Treu of UC Los Angeles, who leads another Webb survey called GLASS, says his team is seeing these early galaxies “form stars like crazy.” They look, he adds, “like giant balls of star formation and nothing else.”

Theorists don’t know if the higher density of matter and higher temperatures of the early universe might have sped star formation. Another theory is that the first stars could have formed faster because they took shape from just the primordial matter leftover from the big bang—hydrogen and helium—without the heavier elements forged by later generations of stars.

Or something may be wrong in the current understanding of how the universe evolves. The prevailing theory of cosmology, known as lambda-CDM (referring to cold dark matter), describes how, soon after the big bang, the unseen dark matter that makes up most of the stuff of the universe clumped together under its own gravity into “halos.” These halos then drew in normal matter and created the conditions for it to condense into galaxies. Lambda-CDM predicts the number and size of halos that should exist in the early universe, and hence the number of galaxies. “There’s not much wiggle room,” Boylan-Kolchin says.

Somerville says it may be possible to tweak lambda-CDM to create something closer to what Webb is seeing. Or, she says, cosmologists may be forced to reassess the first moments of the big bang itself: the era of inflation, a period of rapid growth when quantum fluctuations grew into areas of higher or lower matter density—the seeds of later halos. “If inflation is wrong that could be very fundamental,” she says. “But I wouldn’t bet on it being that.”

Having revealed the early galaxies problem, Webb may provide the data needed to answer it. So far Webb is only seeing young, hot, bright stars in the newfound early galaxies. Follow-up observations of these galaxies at longer wavelengths with Webb’s midinfrared instrument or ground-based radio telescopes sensitive to submillimeter waves could reveal the gas clouds actively building stars. Those observations might help astronomers confirm that early galaxies were unusually prodigious star factories—and hold clues to how they did so.

“In 6 months we’ll have a much better picture of all this,” Boylan-Kolchin says. “It’s a very exciting time.”


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If these images are truly a glimpse into the past and if it's true that the universe is constantly expanding outward from where it started, then is it possible that we could see our solar system in an earlier state?


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Originally Posted by OldColdDawg
If these images are truly a glimpse into the past and if it's true that the universe is constantly expanding outward from where it started, then is it possible that we could see our solar system in an earlier state?

Good questions:

1.) The universe is known to be (to a very good approximation) flat. Which means that light never goes back to where it started. You could imagine a "closed" space-time, by comparison, as sort of the surface of a balloon, where a straight line moving in one direction would eventually come back to the same point. For the universe, it is more like a large sheet of paper, where straight lines just keep going.

Thus, we will never see our "own" solar system -- the light from when our solar system was young is currently very far away from us -- and continuing to move away at the speed of light. However, we can see galaxies that are in a similar state to what our own galaxy looked like when it was young. The Milky Way is not a particularly unusual galaxy -- and so by studying lots of galaxies that are "Milky-Way-like" we can understand how our own galaxy should have evolved.

2.) When we talk about very large distances, we will almost entirely be talking about galaxies, and not individual stars or solar systems. We can only see individual Sun-like stars in our own galaxy (and a handful of very near galaxies like Andromeda). We can generally only "see" planets (and by see, I mean use a number of methods to detect, rather than to really get a picture of) around the few thousand stars that are closest to the Sun in our own galaxy (maybe throughout like 1% of the Milky Way volume). Planets are really really small and dim.

The mind-blowing thing about this telescope is that it is reminding us (yet again) how absolutely huge the universe is.


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Some of these images are incredible!


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I haven't seen any yet that weren't incredible.

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woah... so, does that suggest that Jupiter has a magnetosphere? Is this new or have we known this??
Either way, very cool!


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Originally Posted by PrplPplEater
woah... so, does that suggest that Jupiter has a magnetosphere? Is this new or have we known this??
Either way, very cool!


Jupiter has a massive magnetic field -- according to wiki it was discovered in the 1950s, though I don't know the details: https://en.wikipedia.org/wiki/Magnetosphere_of_Jupiter

The Juno spacecraft was sent to Jupiter, in part, to measure the magnetic field in detail.

Here's a Hubble image of an aurora on Jupiter: https://www.nasa.gov/feature/goddard/2016/hubble-captures-vivid-auroras-in-jupiter-s-atmosphere

The detail on that image, though - is crazy - here's a labeled version of what you are looking at: https://static.timesofisrael.com/www/uploads/2022/08/Untitled-6-4.jpg and a nice thread from a Jupiter expert here: https://twitter.com/physicsJ/status/1561697550310117377

Last edited by Lyuokdea; 08/23/22 02:55 PM.

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That must mean it has a magnetic field, suggesting an iron core?


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Iron and nickel from I've seen.

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Originally Posted by FrankZ
Iron and nickel from I've seen.

Even cooler -- mostly metallic hydrogen -- which is hydrogen at such a high pressure that it is converted into its liquid metal form, which will conduct electricity.

https://en.wikipedia.org/wiki/Metallic_hydrogen

It looks like there have been more recent debates on the abundance of heavier metals
https://www.aanda.org/articles/aa/full_html/2020/06/aa37376-19/aa37376-19.html#R11 -- but my quick read through the literature suggests it is subdominant in terms of generating the magnetic field.


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it's been a while for me and I am not hip to the current. I seem to remember a metallic hydrogen discussion.

Thanks for the updates

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I love educational threads. Thanks for all the knowledge.

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As good a thread as any, and probably not worthy of it's own.

Pretty interesting:


NASA is about to crash a spacecraft into an asteroid. Here's why the mission could one day save humanity.

In a first-of-its-kind maneuver, a spacecraft is set to smash into an asteroid to test whether deflecting a space rock could one day protect Earth from a potentially catastrophic impact.


Sept. 25, 2022, 8:00 AM EDT / Updated Sept. 26, 2022, 10:14 AM EDT
By Denise Chow


More than 6.5 million miles away from Earth, a cosmic collision is imminent.

In a first-of-its-kind maneuver, a NASA spacecraft is set to intentionally smash into an asteroid to test whether deflecting a space rock could one day protect Earth from a potentially catastrophic impact.

The crash is planned for 7:14 p.m. ET Monday. Live coverage will air on NASA TV beginning at 6 p.m. ET.

The mission, known as DART, or the Double Asteroid Redirection Test, will attempt a method of planetary defense that could save Earth from an asteroid on a potential collision course with the planet. It's a rare opportunity to conduct a real-world experiment on an asteroid that doesn't pose a threat to Earth, said Bruce Betts, the chief scientist at the Planetary Society, a nonprofit organization that conducts research, advocacy and outreach to promote space exploration.

"The thing that makes this natural disaster different is that if we do our homework, we can actually prevent it," he said. "That's a huge difference compared to a lot of other large-scale natural disasters."

The DART probe's target is a space rock called Dimorphos, which measures 525 feet across and orbits a much larger, 2,500-foot-wide asteroid named Didymos.

On Monday, the spacecraft will crash into Dimorphos at a blistering speed of around 4 miles per second, or 15,000 mph. The goal isn't to obliterate the asteroid but rather to see whether the collision can alter the space rock's nearly 12-hour orbit.

In a real-life planetary defense situation, even a relatively small nudge could change an asteroid's orbit enough to keep Earth in the clear, Betts said.

"It depends on the size of the object and how much warning time you have, but you do, indeed, just need to change the orbit a little bit," he said.

The DART probe, which is about the size of a small car, will be destroyed in the maneuver, but a small, Italian-built cubesat that was deployed as part of the mission will be able to assess the immediate aftermath.

The tiny satellite, known as LICIACube, will fly within 25 to 50 miles of Dimorphos a few minutes after the crash, Dan Lubey, the LICIACube navigation lead at NASA's Jet Propulsion Laboratory, said in a statement — "close enough to get good images of the impact and ejecta plume, but not so close LICIACube could be hit by ejecta."

Ground-based telescopes will be used to time Dimorphos' orbit and determine whether the mission was a success. A follow-up expedition developed by the European Space Agency will study the impact crater on Dimorphos and conduct more detailed investigations of the asteroid system. That mission, known as Hera, is scheduled to launch in 2024.

"We want to know what happened to Dimorphos, but more important, we want to understand what that means for potentially applying this technique in the future," Nancy Chabot, the DART coordination lead at Johns Hopkins University's Applied Physics Laboratory, said in a news briefing this month. The Applied Physics Lab built and manages the $325 million DART mission for NASA.

No known asteroid larger than 450 feet across has a significant chance of smashing into the planet in the next 100 years, according to NASA, but the agency has said only a fraction of smaller near-Earth objects have been found.

The agency's Planetary Defense Coordination Office is involved with searching for near-Earth objects that could be hazardous to the planet, including those that venture within 5 million miles of Earth's orbit, and objects large enough to cause significant damage if they hit the surface.

Even if the DART mission fails, scientists will learn a lot from the experiment, said Andrea Riley, a program executive in NASA's Planetary Defense Coordination Office.

"If it misses, it still provides a lot of data," Riley said in the news briefing. "This is why we test. We want to do it now rather than when there is an actual need."


https://www.nbcnews.com/science/spa...eroid-mission-one-day-humanity-rcna48918


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Advance to 1:15:00 for the last moment before impact. Pretty crazy, whether you're a space nerd or not!




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Advance to 1:15:00 for the last moment before impact. Pretty crazy, whether you're a space nerd or not!

Bruh- I'm a long-time, oldazz Space Nerd.

I'm now a Space Nerd with daily adult responsibilities, deadlines and obligations.
I truly appreciate the post... especially the shortcut timeline hack.

___________________________


Had this happened back in the Apollo days (and had the net been part of my childhood), I'd have been that kid logging in an hour before the feed even started, staying up late- and forgetting to do his math homework for the next day. Self-truth.

Young Clemmy: recent 6th grade Blerd graduate on an interstellar mission... with sleep deprivation -and poor math grades.


This ish is really cool... and I'm glad I'm still around to see it.
Not every piece of news I see needs to make me feel bad.


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Sounds about the same here.


If everybody had like minds, we would never learn.

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Tackles are tackles.
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Good spot for all updates on the findings of the JWST...

https://www.space.com/topics/james-webb-space-telescope


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