Jump to content

Recommended Posts

Posted
Artist impression of WASP-39 b and its star

The NASA/ESA/CSA James Webb Space Telescope has found definitive evidence for carbon dioxide in the atmosphere of a gas giant planet orbiting a Sun-like star 700 light-years away. The result provides important insights into the composition and formation of the planet, and is indicative of Webb’s ability to also detect and measure carbon dioxide in the thinner atmospheres of smaller rocky planets.

View the full article

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Similar Topics

    • By NASA
      5 min read
      Ultra-low-noise Infrared Detectors for Exoplanet Imaging
      A linear-mode avalanche photodiode array in the test dewar. The detector is the dark square in the center. Michael Bottom, University of Hawai’i One of the ultimate goals in astrophysics is the discovery of Earth-like planets that are capable of hosting life. While thousands of planets have been discovered around other stars, the vast majority of these detections have been made via indirect methods, that is, by detecting the effect of the planet on the star’s light, rather than detecting the planet’s light directly. For example, when a planet passes in front of its host star, the brightness of the star decreases slightly.
      However, indirect methods do not allow for characterization of the planet itself, including its temperature, pressure, gravity, and atmospheric composition. Planetary atmospheres may include “biosignature” gases like oxygen, water vapor, carbon dioxide, etc., which are known to be key ingredients needed to support life as we know it. As such, direct imaging of a planet and characterization of its atmosphere are key to understanding its potential habitability.
      But the technical challenges involved in imaging Earth-like extrasolar planets are extreme. First such planets are detected only by observing light they reflect from their parent star, and so they typically appear fainter than the stars they orbit by factors of about 10 billion. Furthermore, at the cosmic distances involved, the planets appear right next to the stars. A popular expression is that exoplanet imaging is like trying to detect a firefly three feet from a searchlight from a distance of 300 miles.
      Tremendous effort has gone into developing starlight suppression technologies to block the bright glare of the star, but detecting the light of the planet is challenging in its own right, as planets are incredibly faint. One way to quantify the faintness of planetary light is to understand the photon flux rate. A photon is an indivisible particle of light, that is, the minimum detectable amount of light. On a sunny day, approximately 10 thousand trillion photons enter your eye every second. The rate of photons entering your eye from an Earth-like exoplanet around a nearby star would be around 10 to 100 per year. Telescopes with large mirrors can help collect as much of this light as possible, but ultra-sensitive detectors are also needed, particularly for infrared light, where the biosignature gases have their strongest effects. Unfortunately, state-of-the-art infrared detectors are far too noisy to detect the low level of light emitted from exoplanets.
      With support from NASA’s Astrophysics Division and industrial partners, researchers at the University of Hawai’i are developing a promising detector technology to meet these stringent sensitivity requirements. These detectors, known as avalanche photodiode arrays, are constructed out of the same semiconductor material as conventional infrared sensors. However, these new sensors employ an extra “avalanche” layer that takes the signal from a single photon and multiplies it, much like an avalanche can start with a single snowball and quickly grow it to the size of a boulder. This signal amplification occurs before any noise from the detector is introduced, so the effective noise is proportionally reduced. However, at high avalanche levels, photodiodes start to behave badly, with noise exponentially increasing, which negates any benefits of the signal amplification. Late University of Hawai’i faculty member Donald Hall, who was a key figure in driving technology for infrared astronomy, realized the potential use of avalanche photodiodes for ultra-low-noise infrared astronomy with some modifications to the material properties.
      University of Hawai’i team members with cryogenic dewar used to test the sensors. From left to right, Angelu Ramos, Michael Bottom, Shane Jacobson, Charles-Antoine Claveau. Michael Bottom, University of Hawai’i The most recent sensors benefit from a new design including a graded semiconductor bandgap that allows for excellent noise performance at moderate amplification, a mesa pixel geometry to reduce electronic crosstalk, and a read-out integrated circuit to allow for short readout times. “It was actually challenging figuring out just how sensitive these detectors are,” said Michael Bottom, associate professor at the University of Hawai’i and lead of development effort. “Our ‘light-tight’ test chamber, which was designed to evaluate the infrared sensors on the James Webb Space Telescope, was supposed to be completely dark. But when we put these avalanche photodiodes in the chamber, we started seeing light leaks at the level of a photon an hour, which you would never be able to detect using the previous generation of sensors.”
      The new designs have a format of one megapixel, more than ten times larger than the previous iteration of sensors, and circuitry that allows for tracking and subtracting any electronic drifts. Additionally, the pixel size and control electronics are such that these new sensors could be drop-in replacements for the most common infrared sensors used on the ground, which would give new capabilities to existing instruments.
      Image of the Palomar-2 globular cluster located in the constellation of Auriga, taken with the linear-mode avalanche photodiode arrays, taken from the first on-sky testing of the sensors using the University of Hawai’i’s 2.2 meter telescope. Michael Bottom, University of Hawai’i Last year, the team took the first on-sky images from the detectors, using the University of Hawai’i’s 2.2-meter telescope. “It was impressive to see the avalanche process on sky. When we turned up the gain, we could see more stars appear,” said Guillaume Huber, a graduate student working on the project. “The on-sky demonstration was important to prove the detectors could perform well in an operational environment,” added Michael Bottom.
      According to the research team, while the current sensors are a major step forward, the megapixel format is still too small for many science applications, particularly those involving spectroscopy. Further tasks include improving detector uniformity and decreasing persistence. The next generation of sensors will be four times larger, meeting the size requirements for the Habitable Worlds Observatory, NASA’s next envisioned flagship mission, with the goals of imaging and characterizing Earth-like exoplanets.
      Project Lead: Dr. Michael Bottom, University of Hawai’i
      Sponsoring Organization:  NASA Strategic Astrophysics Technology (SAT) Program
      Share








      Details
      Last Updated Feb 18, 2025 Related Terms
      Technology Highlights Astrophysics Astrophysics Division Science-enabling Technology Explore More
      6 min read Webb Reveals Rapid-Fire Light Show From Milky Way’s Central Black Hole


      Article


      5 mins ago
      2 min read Hubble Captures a Cosmic Cloudscape


      Article


      4 days ago
      5 min read Webb Maps Full Picture of How Phoenix Galaxy Cluster Forms Stars


      Article


      5 days ago
      View the full article
    • By NASA
      5 Min Read Webb Maps Full Picture of How Phoenix Galaxy Cluster Forms Stars
      Spectroscopic data collected from NASA’s James Webb Space Telescope is overlayed on an image of the Phoenix cluster that combines data from NASA’s Hubble Space Telescope, Chandra X-ray Observatory and the Very Large Array (VLA) radio telescope. Credits:
      NASA, CXC, NRAO, ESA, M. McDonald (MIT), M. Reefe (MIT), J. Olmsted (STScI) Discovery proves decades-old theory of galaxy feeding cycle.
      Researchers using NASA’s James Webb Space Telescope have finally solved the mystery of how a massive galaxy cluster is forming stars at such a high rate. The confirmation from Webb builds on more than a decade of studies using NASA’s Chandra X-ray Observatory and Hubble Space Telescope, as well as several ground-based observatories.
      The Phoenix cluster, a grouping of galaxies bound together by gravity 5.8 billion light-years from Earth, has been a target of interest for astronomers due to a few unique properties. In particular, ones that are surprising: a suspected extreme cooling of gas and a furious star formation rate despite a roughly 10 billion solar mass supermassive black hole at its core. In other observed galaxy clusters, the central supermassive black hole powers energetic particles and radiation that prevents gas from cooling enough to form stars. Researchers have been studying gas flows within this cluster to try to understand how it is driving such extreme star formation.
      Image A: Phoenix Cluster (Hubble, Chandra, VLA Annotated)
      Spectroscopic data collected from NASA’s James Webb Space Telescope is overlayed on an image of the Phoenix cluster that combines data from NASA’s Hubble Space Telescope, Chandra X-ray Observatory and the Very Large Array (VLA) radio telescope. Webb’s powerful sensitivity in the mid-infrared detected the cooling gas that leads to a furious rate of star formation in this massive galaxy cluster. Credit: NASA, CXC, NRAO, ESA, M. McDonald (MIT), M. Reefe (MIT), J. Olmsted (STScI) “We can compare our previous studies of the Phoenix cluster, which found differing cooling rates at different temperatures, to a ski slope,” said Michael McDonald of the Massachusetts Institute of Technology in Cambridge, principal investigator of the program. “The Phoenix cluster has the largest reservoir of hot, cooling gas of any galaxy cluster — analogous to having the busiest chair lift, bringing the most skiers to the top of the mountain. However, not all of those skiers were making it down the mountain, meaning not all the gas was cooling to low temperatures. If you had a ski slope where there were significantly more people getting off the ski lift at the top than were arriving at the bottom, that would be a problem!”
      To date, in the Phoenix cluster, the numbers weren’t adding up, and researchers were missing a piece of the process. Webb has now found those proverbial skiers at the middle of the mountain, in that it has tracked and mapped the missing cooling gas that will ultimately feed star formation. Most importantly, this intermediary warm gas was found within cavities tracing the very hot gas, a searing 18 million degrees Fahrenheit, and the already cooled gas around 18,000 degrees Fahrenheit.
      The team studied the cluster’s core in more detail than ever before with the Medium-Resolution Spectrometer on Webb’s Mid-Infrared Instrument (MIRI). This tool allows researchers to take two-dimenstional spectroscopic data from a region of the sky, during one set of observations.
      “Previous studies only measured gas at the extreme cold and hot ends of the temperature distribution throughout the center of the cluster,” added McDonald. “We were limited — it was not possible to detect the ‘warm’ gas that we were looking for. With Webb, we could do this for the first time.”
      Image B: Phoenix Cluster (Hubble, Chandra, VLA)
      This image of the Phoenix cluster combines data from NASA’s Hubble Space Telescope, Chandra X-ray Observatory, and the Very Large Array radio telescope. X-rays from Chandra depict extremely hot gas in purple. Optical light data from Hubble show galaxies in yellow, and filaments of cooler gas where stars are forming in light blue. Outburst generated jets, represented in red, are seen in radio waves by the VLA radio telescope. NASA, CXC, NRAO, ESA, M. McDonald (MIT). A Quirk of Nature
      Webb’s capability to detect this specific temperature of cooling gas, around 540,000 degrees Fahrenheit, is in part due to its instrumental capabilities. However, the researchers are getting a little help from nature, as well.
      This oddity involves two very different ionized atoms, neon and oxygen, created in similar environments. At these temperatures, the emission from oxygen is 100 times brighter but is only visible in ultraviolet. Even though the neon is much fainter, it glows in the infrared, which allowed the researchers to take advantage of Webb’s advanced instruments.
      “In the mid-infrared wavelengths detected by Webb, the neon VI signature was absolutely booming,” explained Michael Reefe, also of the Massachusetts Institute of Technology, lead author on the paper published in Nature. “Even though this emission is usually more difficult to detect, Webb’s sensitivity in the mid-infrared cuts through all of the noise.”
      The team now hopes to employ this technique to study more typical galaxy clusters. While the Phoenix cluster is unique in many ways, this proof of concept is an important step towards learning about how other galaxy clusters form stars.The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing 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).
      Downloads
      Right click any image to save it or open a larger version in a new tab/window via the browser’s popup menu.
      View/Download all image products at all resolutions for this article from the Space Telescope Science Institute.
      Read the research paper published in Nature.
      Media Contacts
      Laura Betz – laura.e.betz@nasa.gov
      NASA’s Goddard Space Flight Center, Greenbelt, Md.
      Hannah Braun hbraun@stsci.edu
      Space Telescope Science Institute, Baltimore, Md.
      Christine Pulliam – cpulliam@stsci.edu
      Space Telescope Science Institute, Baltimore, Md.
      Related Information
      More Webb News
      More Webb Images
      Webb Science Themes
      Webb Mission Page
      Article: Large-scale Structures
      Article: Phoenix Galaxy Cluster’s black hole
      Article: Spectroscopy 101
      Related For Kids
      What is the Webb Telescope?
      SpacePlace for Kids
      En Español
      Ciencia de la NASA
      NASA en español 
      Space Place para niños
      Keep Exploring Related Topics
      James Webb Space Telescope


      Webb is the premier observatory of the next decade, serving thousands of astronomers worldwide. It studies every phase in the…


      Stars



      Galaxies



      Hubble Space Telescope


      Since its 1990 launch, the Hubble Space Telescope has changed our fundamental understanding of the universe.

      View the full article
    • By NASA
      This artist’s concept visualizes a super-Neptune world orbiting a low-mass star near the center of our Milky Way galaxy. Scientists recently discovered such a system that may break the current record for fastest exoplanet system, traveling at least 1.2 million miles per hour, or 540 kilometers per second.NASA/JPL-Caltech/R. Hurt (Caltech-IPAC) Astronomers may have discovered a scrawny star bolting through the middle of our galaxy with a planet in tow. If confirmed, the pair sets a new record for the fastest-moving exoplanet system, nearly double our solar system’s speed through the Milky Way.
      The planetary system is thought to move at least 1.2 million miles per hour, or 540 kilometers per second.
      “We think this is a so-called super-Neptune world orbiting a low-mass star at a distance that would lie between the orbits of Venus and Earth if it were in our solar system,” said Sean Terry, a postdoctoral researcher at the University of Maryland, College Park and NASA’s Goddard Space Flight Center in Greenbelt, Maryland. Since the star is so feeble, that’s well outside its habitable zone. “If so, it will be the first planet ever found orbiting a hypervelocity star.”
      A paper describing the results, led by Terry, was published in The Astronomical Journal on February 10.
      A Star on the Move
      The pair of objects was first spotted indirectly in 2011 thanks to a chance alignment. A team of scientists combed through archived data from MOA (Microlensing Observations in Astrophysics) – a collaborative project focused on a microlensing survey conducted using the University of Canterbury Mount John Observatory in New Zealand — in search of light signals that betray the presence of exoplanets, or planets outside our solar system.
      Microlensing occurs because the presence of mass warps the fabric of space-time. Any time an intervening object appears to drift near a background star, light from the star curves as it travels through the warped space-time around the nearer object. If the alignment is especially close, the warping around the object can act like a natural lens, amplifying the background star’s light.
      This artist’s concept visualizes stars near the center of our Milky Way galaxy. Each has a colorful trail indicating its speed –– the longer and redder the trail, the faster the star is moving. NASA scientists recently discovered a candidate for a particularly speedy star, visualized near the center of this image, with an orbiting planet. If confirmed, the pair sets a record for fastest known exoplanet system.NASA/JPL-Caltech/R. Hurt (Caltech-IPAC) In this case, microlensing signals revealed a pair of celestial bodies. Scientists determined their relative masses (one is about 2,300 times heavier than the other), but their exact masses depend on how far away they are from Earth. It’s sort of like how the magnification changes if you hold a magnifying glass over a page and move it up and down.
      “Determining the mass ratio is easy,” said David Bennett, a senior research scientist at the University of Maryland, College Park and NASA Goddard, who co-authored the new paper and led the original study in 2011. “It’s much more difficult to calculate their actual masses.”
      The 2011 discovery team suspected the microlensed objects were either a star about 20 percent as massive as our Sun and a planet roughly 29 times heavier than Earth, or a nearer “rogue” planet about four times Jupiter’s mass with a moon smaller than Earth.
      To figure out which explanation is more likely, astronomers searched through data from the Keck Observatory in Hawaii and ESA’s (European Space Agency’s) Gaia satellite. If the pair were a rogue planet and moon, they’d be effectively invisible – dark objects lost in the inky void of space. But scientists might be able to identify the star if the alternative explanation were correct (though the orbiting planet would be much too faint to see).
      They found a strong suspect located about 24,000 light-years away, putting it within the Milky Way’s galactic bulge — the central hub where stars are more densely packed. By comparing the star’s location in 2011 and 2021, the team calculated its high speed.
      This Hubble Space Telescope image shows a bow shock around a very young star called LL Ori. Named for the crescent-shaped wave made by a ship as it moves through water, a bow shock can be created in space when two streams of gas collide. Scientists think a similar feature may be present around a newfound star that could be traveling at least 1.2 million miles per hour, or 540 kilometers per second. Traveling at such a high velocity in the galactic bulge (the central part of the galaxy) where gas is denser could generate a bow shock. NASA and The Hubble Heritage Team (STScI/AURA); Acknowledgment: C. R. O’Dell (Vanderbilt University) But that’s just its 2D motion; if it’s also moving toward or away from us, it must be moving even faster. Its true speed may even be high enough to exceed the galaxy’s escape velocity of just over 1.3 million miles per hour, or about 600 kilometers per second. If so, the planetary system is destined to traverse intergalactic space many millions of years in the future.
      “To be certain the newly identified star is part of the system that caused the 2011 signal, we’d like to look again in another year and see if it moves the right amount and in the right direction to confirm it came from the point where we detected the signal,” Bennett said.
      “If high-resolution observations show that the star just stays in the same position, then we can tell for sure that it is not part of the system that caused the signal,” said Aparna Bhattacharya, a research scientist at the University of Maryland, College Park and NASA Goddard who co-authored the new paper. “That would mean the rogue planet and exomoon model is favored.”
      NASA’s upcoming Nancy Grace Roman Space Telescope will help us find out how common planets are around such speedy stars, and may offer clues to how these systems are accelerated. The mission will conduct a survey of the galactic bulge, pairing a large view of space with crisp resolution.
      “In this case we used MOA for its broad field of view and then followed up with Keck and Gaia for their sharper resolution, but thanks to Roman’s powerful view and planned survey strategy, we won’t need to rely on additional telescopes,” Terry said. “Roman will do it all.”
      Download additional images and video from NASA’s Scientific Visualization Studio.
      By Ashley Balzer
      NASA’s Goddard Space Flight Center, Greenbelt, Md.
      Media contact:
      Claire Andreoli
      NASA’s Goddard Space Flight Center, Greenbelt, Md.
      301-286-1940
      Share
      Details
      Last Updated Feb 10, 2025 EditorAshley BalzerContactAshley Balzerashley.m.balzer@nasa.govLocationGoddard Space Flight Center Related Terms
      Exoplanets Astrophysics Exoplanet Discoveries Exoplanet Science Goddard Space Flight Center Nancy Grace Roman Space Telescope Neptune-Like Exoplanets Science & Research Studying Exoplanets The Universe Explore More
      4 min read Discovery Alert: With Six New Worlds, 5,500 Discovery Milestone Passed!
      On Aug. 24, 2023, more than three decades after the first confirmation of planets beyond…
      Article 7 months ago 3 min read Discovery Alert: Water Vapor Detected on a ‘Super Neptune’
      The atmosphere of a “super Neptune” some 150 light-years distant contains water vapor, a new…
      Article 3 years ago 6 min read Why NASA’s Roman Mission Will Study Milky Way’s Flickering Lights
      Article 1 year ago
      View the full article
    • By European Space Agency
      This new NASA/ESA/CSA James Webb Space Telescope Picture of the Month presents HH 30 in unprecedented detail. This target is an edge-on protoplanetary disc that is surrounded by jets and a disc wind, and is located in the dark cloud LDN 1551 in the Taurus Molecular Cloud. 
      View the full article
  • Check out these Videos

×
×
  • Create New...