jwst Archives

August 29, 2024August 31, 2024 by Matt Williams

Remember those Impossible Galaxies Found by JWST? It Turns Out They Were Possible After All

This is a small portion of the field observed by NASA’s James Webb Space Telescope’s NIRCam (Near-Infrared Camera) for the Cosmic Evolution Early Release Science (CEERS) survey. It is filled with galaxies. The light from some of them has traveled for over 13 billion years to reach the telescope. Credit: NASA, ESA, CSA, Steve Finkelstein (University of Texas at Austin)

When the James Webb Space Telescope provided astronomers with a glimpse of the earliest galaxies in the Universe, there was some understandable confusion. Given that these galaxies existed during “Cosmic Dawn,” less than one billion years after the Big Bang, they seemed “impossibly large” for their age. According to the most widely accepted cosmological model—the Lambda Cold Dark Matter (LCDM) model—the first galaxies in the Universe did not have enough time to become so massive and should have been more modestly sized.

This presented astronomers with another “crisis in cosmology,” suggesting that the predominant model about the origins and evolution of the Universe was wrong. However, according to a new study by an international team of astronomers, these galaxies are not so “impossibly large” after all, and what we saw may have been the result of an optical illusion. In short, the presence of black holes in some of these early galaxies made them appear much brighter and larger than they actually were. This is good news for astronomers and cosmologists who like the LCDM the way it is!

August 29, 2024August 29, 2024 by Matt Williams

Webb Discovers Six New “Rogue Worlds” that Provide Clues to Star Formation

This stunning new mosaic of images from the NASA/ESA/CSA James Webb Space Telescope showcases the nearby star-forming cluster, NGC 1333. Credit: ESA/Webb, NASA & CSA, A. Scholz, K. Muzic, A. Langeveld, R. Jayawardhana

Rogue Planets, or free-floating planetary-mass objects (FFPMOs), are planet-sized objects that either formed in interstellar space or were part of a planetary system before gravitational perturbations kicked them out. Since they were first observed in 2000, astronomers have detected hundreds of candidates that are untethered to any particular star and float through the interstellar medium (ISM) of our galaxy. In fact, some scientists estimate that there could be as many as 2 trillion rogue planets (or more!) wandering through the Milky Way alone.

In recent news, a team of astronomers working with the James Webb Space Telescope (JWST) announced the discovery of six rogue planet candidates in an unlikely spot. The planets, which include the lightest rogue planet ever identified (with a debris disk around it), were spotted during Webb‘s deepest survey of the young nebula NGC 1333, a star-forming cluster about a thousand light-years away in the Perseus constellation. These planets could teach astronomers a great deal about the formation process of stars and planets.

August 5, 2024August 5, 2024 by Evan Gough

Fast-Tracking the Search for Habitable Worlds

Illustration: Assortment of exoplanets — Astronomers have detected thousands of planets, including dozens that are potentially habitable. To winnow them down, they need to understand their atmospheres. AI and machine learning can help. (NASA Illustration)

Modern astronomy would struggle without AI and machine learning (ML), which have become indispensable tools. They alone have the capability to manage and work with the vast amounts of data that modern telescopes generate. ML can sift through large datasets, seeking specified patterns that would take humans far longer to find.

The search for biosignatures on Earth-like exoplanets is a critical part of contemporary astronomy, and ML can play a big role in it.

July 25, 2024July 25, 2024 by Mark Thompson

Why is JWST Having So Much Trouble with the TRAPPIST-1 System?

A new step-by-step roadmap describes how to improve the efficiency of data gathering with the JWST to benefit the astronomy community at large. “Our hope now is that a large-scale community effort guided by the roadmap can be initiated to yield deliverables at a timely pace,” says MIT Associate Professor Julien de Wit. Credits:Image components courtesy of NASA/JPL-Caltech.

When the James Webb Space Telescope was launched it came with a fanfare expecting amazing things, much like the Hubble Space Telescope. One of JWST’s most anticipated target was TRAPPIST-1. This inconspicuous star is host to seven Earth-sized planets, with at least three in the habitable zone. The two inner planets are airless worlds but so far there has been no word of the third planet, the first in the habitable zone. The question is why and what makes it so tricky to observe?

July 16, 2024July 16, 2024 by Matt Williams

New Images From Webb Reveal Jupiter's Complex Atmosphere

New observations of the Great Red Spot on Jupiter have revealed that the planet’s atmosphere above and around the infamous storm is surprisingly interesting and active. Credit: ESA

The James Webb Space Telescope (JWST) has accomplished some spectacular feats since it began operations in 2021. Thanks to its sensitivity in the near- and mid-infrared wavelengths, it can take detailed images of cooler objects and reveal things that would otherwise go unnoticed. This includes the iconic image Webb took of Jupiter in August 2022, which showed the planet’s atmospheric features (including its polar aurorae and Great Red Spot) in a new light. Using Webb, a team of European astronomers recently observed the region above the Great Red Spot and discovered previously unseen features.

July 9, 2024July 9, 2024 by Mark Thompson

Do Planets Have the Raw Ingredients for Life? The Answer is in their Stars

Finding planets that already have, or have the ingredients for intelligent life is a real challenge. It is exciting that new telescopes and spacecraft are in development that will start to identify candidate planets. Undertaking these observations will take significant amounts of telescope time so we need to find some way to prioritise which ones to look at first. A new paper has been published that suggests we can study the host stars first for the necessary raw elements giving a more efficient way to hunt for similar worlds to Earth.

June 17, 2024June 17, 2024 by Evan Gough

Almost a Third of Early Galaxies Were Already Spirals

The graceful winding arms of the grand-design spiral galaxy M51 stretch across this image from the NASA/ESA/CSA James Webb Space Telescope. New JWST observations of the early Universe are upending our understanding of galaxy evolution. Credit: ESA/Webb, NASA & CSA, A. Adamo (Stockholm University) and the FEAST JWST team

In the years before the JWST’s launch, astronomers’ efforts to understand the early Universe were stymied by a stubborn obstacle: the light from the early Universe was red-shifted to an extreme degree. The JWST was built with extreme redshifts in mind, and one of its goals was to study Galaxy Assembly.

Once the JWST activated its segmented, beryllium eye, the Universe’s most ancient, red-shifted light became visible.

June 14, 2024June 14, 2024 by Scott Alan Johnston

Webb is an Amazing Supernova Hunter

80 objects (circled in green) that changed in brightness over time, as seen by JWST. Most of these are supernovae. NASA, ESA, CSA, STScI, JADES Collaboration

The James Webb Space Telescope (JWST) has just increased the number of known distant supernovae by tenfold. This rapid expansion of astronomers’ catalog of supernovae is extremely valuable, not least because it improves the reliability of measurements for the expansion of the universe.

June 13, 2024June 13, 2024 by Evan Gough

Sulphur Makes A Surprise Appearance in this Exoplanet’s Atmosphere

This artist's illustration shows the Neptune-like exoplanet GJ 3470b, which has an atmosphere rich in sulphur. The planet's atmosphere holds clues to how it and other similar planets formed. Image Credit: Department of Astronomy, UW–Madison

At our current level of knowledge, many exoplanet findings take us by surprise. The only atmospheric chemistry we can see with clarity is Earth’s, and we still have many unanswered questions about how our planet and its atmosphere developed. With Earth as our primary reference point, many things about exoplanet atmospheres seem puzzling in comparison and generate excitement and deeper questions.

That’s what’s happened with GJ-3470 b, a Neptune-like exoplanet about 96 light-years away.

June 11, 2024June 11, 2024 by Mark Thompson

Webb Sees Asteroids Collide in Another Star System

Asteroid collision: CREDIT:NASA/LYNETTE COOK

The James Webb Space Telescope (JWST) continues to make amazing discoveries. This time in the constellation of Pictor where, in the Beta Pictoris system a massive collision of asteroids. The system is young and only just beginning its evolutionary journey with planets only now starting to form. Just recently, observations from JWST have shown significant energy changes emitted by dust grains in the system compared to observations made 20 years ago. Dust production was thought to be ongoing but the results showed the data captured 20 years ago may have been a one-off event that has since faded suggesting perhaps, an asteroid strike!