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Post by swamprat on Jul 8, 2022 19:55:21 GMT
NASA reveals details about James Webb Space Telescope's first full-color images
Kris Holt · Contributing Reporter Fri, July 8, 2022
It's only a few days until NASA and its partners on the James Webb Space Telescope project reveal the first full-color images and spectroscopic data captured by the observatory. The agency has shed a little more light on what to expect by revealing the JWST's initial list of cosmic targets.
One of them is the Carina Nebula, which is around 7,600 light years away. NASA says it's one of the biggest and brightest nebulae in the sky and it includes stars that are several times larger than the Sun. Another nebula the telescope captured images from is the Southern Ring. That's roughly 2,000 light years from Earth and is a planetary nebula — it's an expanding cloud of gas that surrounds a dying star.
Closer to home is the gas planet WASP-96 b, which is almost 1,150 light years away and has around half the mass of Jupiter. NASA will provide a look at the planet's light spectrum data. Much further from here is Stephan’s Quintet, which is around 290 million light years away in the Pegasus constellation. This is the first compact galaxy group that was discovered, all the way back in 1877. It comprises five galaxies, four of which "are locked in a cosmic dance of repeated close encounters," NASA said.
Also on Tuesday, NASA, the European Space Agency and Canadian Space Agency will reveal imagery for SMACS 0723. "Massive foreground galaxy clusters magnify and distort the light of objects behind them, permitting a deep field view into both the extremely distant and intrinsically faint galaxy populations," NASA explained.
A committee of experts from NASA, ESA, CSA and the Space Telescope Science Institute spent five years determining the first targets for Webb's instruments. The full-color images and spectroscopic data that JSWT captured will be revealed on July 12th at 10:30AM ET. You'll be able to view them on NASA's website.
This marks an important step for JWST as it marks the official beginning of the observatory's general science operations. The aim is to provide us with more detailed images and information about the earliest stars and galaxies as well as potentially habitable exoplanets. After launch in December, it took several months for the JWST to reach its destination and prepare for full operation. We're very close to finding out just what the observatory is capable of.www.yahoo.com/finance/news/nasa-james-webb-space-telescope-first-targets-images-data-172517196.html
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Post by swamprat on Jul 11, 2022 23:59:04 GMT
Looking back 13 billion years
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Post by X on Jul 12, 2022 15:52:26 GMT
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Post by X on Jul 12, 2022 17:01:24 GMT
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Post by swamprat on Jul 17, 2022 0:31:29 GMT
A New Era in the Search for Extraterrestrial Life: We Can Finally Analyze Exoplanet Atmospheres By Chris Impey and Daniel Apai -July 15, 2022
The ingredients for life are spread throughout the universe. While Earth is the only known place in the universe with life, detecting life beyond Earth is a major goal of modern astronomy and planetary science.
We are two scientists who study exoplanets and astrobiology. Thanks in large part to next-generation telescopes like James Webb, researchers like us will soon be able to measure the chemical makeup of atmospheres of planets around other stars. The hope is that one or more of these planets will have a chemical signature of life.
Habitable Exoplanets
Life might exist in the solar system where there is liquid water—like the subsurface aquifers on Mars or in the oceans of Jupiter’s moon Europa. However, searching for life in these places is incredibly difficult, as they are hard to reach and detecting life would require sending a probe to return physical samples.
Many astronomers believe there’s a good chance that life exists on planets orbiting other stars, and it’s possible that’s where life will first be found.
Theoretical calculations suggest that there are around 300 million potentially habitable planets in the Milky Way galaxy alone and several habitable Earth-sized planets within only 30 light-years of Earth—essentially humanity’s galactic neighbors. So far, astronomers have discovered over 5,000 exoplanets, including hundreds of potentially habitable ones, using indirect methods that measure how a planet affects its nearby star. These measurements can give astronomers information on the mass and size of an exoplanet, but not much else.
Looking for Biosignatures
To detect life on a distant planet, astrobiologists will study starlight that has interacted with a planet’s surface or atmosphere. If the atmosphere or surface was transformed by life, the light may carry a clue, called a biosignature.
For the first half of its existence, Earth sported an atmosphere without oxygen, even though it hosted simple, single-celled life. Earth’s biosignature was very faint during this early era. That changed abruptly 2.4 billion years ago when a new family of algae evolved. The algae used a process of photosynthesis that produces free oxygen—oxygen that isn’t chemically bonded to any other element. From that time on, Earth’s oxygen-filled atmosphere has left a strong and easily detectable biosignature on light that passes through it.
When light bounces off the surface of a material or passes through a gas, certain wavelengths of the light are more likely to remain trapped in the gas or material’s surface than others. This selective trapping of wavelengths of light is why objects are different colors. Leaves are green because chlorophyll is particularly good at absorbing light in the red and blue wavelengths. As light hits a leaf, the red and blue wavelengths are absorbed, leaving mostly green light to bounce back into your eyes.
The pattern of missing light is determined by the specific composition of the material the light interacts with. Because of this, astronomers can learn something about the composition of an exoplanet’s atmosphere or surface by, in essence, measuring the specific color of light that comes from a planet.
This method can be used to recognize the presence of certain atmospheric gases that are associated with life—such as oxygen or methane—because these gases leave very specific signatures in light. It could also be used to detect peculiar colors on the surface of a planet. On Earth, for example, the chlorophyll and other pigments plants and algae use for photosynthesis capture specific wavelengths of light. These pigments produce characteristic colors that can be detected by using a sensitive infrared camera. If you were to see this color reflecting off the surface of a distant planet, it would potentially signify the presence of chlorophyll.
Telescopes in Space and on Earth
It takes an incredibly powerful telescope to detect these subtle changes to the light coming from a potentially habitable exoplanet. For now, the only telescope capable of such a feat is the new James Webb Space Telescope. As it began science operations in July 2022, James Webb took a reading of the spectrum of the gas giant exoplanet WASP-96b. The spectrum showed the presence of water and clouds, but a planet as large and hot as WASP-96b is unlikely to host life.
However, this early data shows that James Webb is capable of detecting faint chemical signatures in light coming from exoplanets. In the coming months, Webb is set to turn its mirrors toward TRAPPIST-1e, a potentially habitable Earth-sized planet a mere 39 light-years from Earth.
Webb can look for biosignatures by studying planets as they pass in front of their host stars and capturing starlight that filters through the planet’s atmosphere. But Webb was not designed to search for life, so the telescope is only able to scrutinize a few of the nearest potentially habitable worlds. It also can only detect changes to atmospheric levels of carbon dioxide, methane and water vapor. While certain combinations of these gasses may suggest life, Webb is not able to detect the presence of unbonded oxygen, which is the strongest signal for life.
Leading concepts for future, even more powerful, space telescopes include plans to block the bright light of a planet’s host star to reveal starlight reflected back from the planet. This idea is similar to using your hand to block sunlight to better see something in the distance. Future space telescopes could use small, internal masks or large, external, umbrella-like spacecraft to do this. Once the starlight is blocked, it becomes much easier to study light bouncing off a planet.
There are also three enormous, ground-based telescopes currently under construction that will be able to search for biosignatures: the Giant Magellen Telescope, the Thirty Meter Telescope, and the European Extremely Large Telescope. Each is far more powerful than existing telescopes on Earth, and despite the handicap of Earth’s atmosphere distorting starlight, these telescopes might be able to probe the atmospheres of the closest worlds for oxygen.
Is it Biology or Geology?
Even using the most powerful telescopes of the coming decades, astrobiologists will only be able to detect strong biosignatures produced by worlds that have been completely transformed by life.
Unfortunately, most gases released by terrestrial life can also be produced by nonbiological processes—cows and volcanoes both release methane. Photosynthesis produces oxygen, but sunlight does, too, when it splits water molecules into oxygen and hydrogen. There is a good chance astronomers will detect some false positives when looking for distant life. To help rule out false positives, astronomers will need to understand a planet of interest well enough to understand whether its geologic or atmospheric processes could mimic a biosignature.
The next generation of exoplanet studies has the potential to pass the bar of the extraordinary evidence needed to prove the existence of life. The first data released from the James Webb Space Telescope gives us a sense of the exciting progress that’s coming soon.
singularityhub.com/2022/07/15/a-new-era-for-alien-hunters-we-can-finally-see-into-exoplanet-atmospheres/
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Post by X on Jul 20, 2022 17:03:37 GMT
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Post by X on Jul 22, 2022 21:31:01 GMT
Astronomy Picture of the Day Spiral Galaxy M74: A Sharper View Image Credit: NASA, ESA, CSA, STScI; Processing Copyright: Robert Eder Explanation: Beautiful spiral galaxy Messier 74 (also known as NGC 628) lies some 32 million light-years away toward the constellation Pisces. An island universe of about 100 billion stars with two prominent spiral arms, M74 has long been admired by astronomers as a perfect example of a grand-design spiral galaxy. M74's central region is brought into a stunning, sharp focus in this recently processed image using publicly available data from the James Webb Space Telescope. The colorized combination of image data sets is from two of Webb's instruments NIRcam and MIRI, operating at near- and mid-infrared wavelengths. It reveals cooler stars and dusty structures in the grand-design spiral galaxy only hinted at in previous space-based views. apod.nasa.gov/apod/
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Post by X on Aug 2, 2022 19:10:18 GMT
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Post by swamprat on Aug 24, 2022 14:35:08 GMT
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Post by X on Sept 6, 2022 19:27:54 GMT
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Post by X on Sept 6, 2022 19:28:54 GMT
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Post by purr on Sept 7, 2022 9:24:13 GMT
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Post by X on Oct 9, 2022 16:34:09 GMT
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Post by X on Oct 20, 2022 14:49:06 GMT
Oct 19, 2022 NASA’s Webb Takes Star-Filled Portrait of Pillars of Creation The Pillars of Creation are set off in a kaleidoscope of color in NASA’s James Webb Space Telescope’s near-infrared-light view. The pillars look like arches and spires rising out of a desert landscape, but are filled with semi-transparent gas and dust, and ever changing. This is a region where young stars are forming – or have barely burst from their dusty cocoons as they continue to form. Credits: NASA, ESA, CSA, STScI; Joseph DePasquale (STScI), Anton M. Koekemoer (STScI), Alyssa Pagan (STScI). Download the full-resolution, uncompressed version and supporting visuals from the Space Telescope Science Institute.
Lee esta historia en español aquí. NASA’s James Webb Space Telescope has captured a lush, highly detailed landscape – the iconic Pillars of Creation – where new stars are forming within dense clouds of gas and dust. The three-dimensional pillars look like majestic rock formations, but are far more permeable. These columns are made up of cool interstellar gas and dust that appear – at times – semi-transparent in near-infrared light. Webb’s new view of the Pillars of Creation, which were first made famous when imaged by NASA’s Hubble Space Telescope in 1995, will help researchers revamp their models of star formation by identifying far more precise counts of newly formed stars, along with the quantities of gas and dust in the region. Over time, they will begin to build a clearer understanding of how stars form and burst out of these dusty clouds over millions of years. NASA's Hubble Space Telescope made the Pillars of Creation famous with its first image in 1995, but revisited the scene in 2014 to reveal a sharper, wider view in visible light, shown above at left. A new, near-infrared-light view from NASA’s James Webb Space Telescope, at right, helps us peer through more of the dust in this star-forming region. The thick, dusty brown pillars are no longer as opaque and many more red stars that are still forming come into view. Credits: NASA, ESA, CSA, STScI; Joseph DePasquale (STScI), Anton M. Koekemoer (STScI), Alyssa Pagan (STScI).
Newly formed stars are the scene-stealers in this image from Webb’s Near-Infrared Camera (NIRCam). These are the bright red orbs that typically have diffraction spikes and lie outside one of the dusty pillars. When knots with sufficient mass form within the pillars of gas and dust, they begin to collapse under their own gravity, slowly heat up, and eventually form new stars. What about those wavy lines that look like lava at the edges of some pillars? These are ejections from stars that are still forming within the gas and dust. Young stars periodically shoot out supersonic jets that collide with clouds of material, like these thick pillars. This sometimes also results in bow shocks, which can form wavy patterns like a boat does as it moves through water. The crimson glow comes from the energetic hydrogen molecules that result from jets and shocks. This is evident in the second and third pillars from the top – the NIRCam image is practically pulsing with their activity. These young stars are estimated to be only a few hundred thousand years old. Continue here (With Youtube video - Cast it on the big screen) at NASA Goddard : www.nasa.gov/feature/goddard/2022/nasa-s-webb-takes-star-filled-portrait-of-pillars-of-creation
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Post by X on Oct 23, 2022 17:07:47 GMT
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