JWST tagged posts

First-ever Detection of a Mid-Infrared Flare in SagittariusA*, the Milky Way’s supermassive black hole

Using the MIRI instrument onboard the James Webb Space Telescope, an international team of scientists made the first-ever detection of a mid-IR flare from Sagittarius A*, the supermassive blackhole at the heart of the Milky Way. In simultaneous radio observations, the team found a radio counterpart of the flare lagging behind in time. The paper is published on the arXiv preprint server.

Scientists have been actively observing Sagittarius A* (Sgr A)—a supermassive black hole roughly 4 million times the mass of the sun— since the early 1990s. Sgr A regularly exhibits flares that can be observed in multiple wavelengths, allowing scientists to see different views of the same flare and better understand how it emits light and how the emission is generated...

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Astronomers discover an Ultra-Massive Grand-Design Spiral Galaxy

Astronomers discover an ultra-massive grand-design spiral galaxy
The morphology and photometric redshift of Zhúlóng. Credit: Xiao et al., 2024.

Using the James Webb Space Telescope (JWST), an international team of astronomers has detected a new grand-design spiral galaxy as part of the PANORAMIC survey. The newfound galaxy, named Zhúlóng, is extremely massive and appears to be the most distant spiral galaxy identified so far. The finding was detailed in a paper published December 17 on the pre-print server arXiv.

Grand-design spiral galaxies are characterized by their prominent, well-defined arms, which circle outwards from a clear core. It is assumed that the arms in such galaxies are actually overdense regions of the disk which trigger star formation as incoming material is compressed in that region.

It is still not well understood when ...

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Does the Exoplanet Trappist-1 b have an Atmosphere after all?

New observations reveal the challenges of detecting planetary atmospheres

Recent measurements with the James Webb Space Telescope (JWST) cast doubt on the current understanding of the exoplanet Trappist-1 b’s nature. Until now, it was assumed to be a dark rocky planet without an atmosphere, shaped by a billion-year-long cosmic impact of radiation and meteorites. The opposite appears to be true. The surface shows no signs of weathering, which could indicate geological activity such as volcanism and plate tectonics. Alternatively, a planet with a hazy atmosphere composed of carbon dioxide is also viable. The results demonstrate the challenges of determining the properties of exoplanets with thin atmospheres.

Trappist-1 b is one of seven rocky planets orbiting the star Trappist-1, ...

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MAUVE: An Ultraviolet Astrophysics Probe Mission Concept

For the past 30 years, NASA’s Great Observatories—the Hubble, Spitzer, Compton, and Chandra space telescopes—have revealed some amazing things about the universe. In addition to some of the deepest views of the universe provided by the Hubble Deep Fields campaign, these telescopes have provided insight into the unseen parts of the cosmos—i.e., in the infrared, gamma-ray, and ultraviolet spectrums.

With the success of these observatories and the James Webb Space Telescope (JWST), NASA is contemplating future missions that would reveal even more of the “unseen universe.”

This includes the UltraViolet Explorer (UVEX), a space telescope NASA plans to launch in 2030 as its next Astrophysics Medium-Class Explorer mission...

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