Astronomy / Astrophysics

A group of galaxies observed by the James Webb Space Telescope (Image NASA, ESA, CSA)

An article published in “The Astrophysical Journal” reports the results of a new measurement of the universe’s expansion rate obtained using observations conducted with the James Webb Space Telescope that confirms previous results obtained with Hubble. A team of researchers led by Adam Riess, who has been investigating the expansion of the universe for years, verified that the so-called Hubble tension, as the discrepancy between different measurements is called, was not due to limitations of the Hubble Space Telescope. According to Riess, this result confirms that our cosmological models are incomplete and there may be something we don’t yet understand about the universe.

The galaxy NGC 2090 as seen by the James Webb Space Telescope (ESA/Webb, NASA & CSA, A. Leroy)

ESA has published an image captured by the James Webb Space Telescope that portrays the galaxy NGC 2090 in the near and mid-infrared thanks to the combination of the MIRI (Mid-InfraRed Instrument) and NIRCam (Near-InfraRed Camera) instruments. This allowed to obtain an unprecedented amount of detail on this galaxy’s two spiral arms. For ESA, which participates in various astronomical missions, NGC 2090 is at the center of the scene these days because the choice for the Webb image of the month follows by a few days the choice for the Hubble Space Telescope image of the week, captured using various WFC3 (Wide Field Camera 3) instrument’s filters in the visible frequencies and an ultraviolet filter.

Artist's concept of the exoplanet TOI-3261 b being struck by stellar wind (Image NASA/JPL-Caltech/K. Miller (Caltech/IPAC))

An article published in “The Astronomical Journal” reports the identification of the exoplanet TOI-3261 b, an ultrahot Neptune very close to its star, one of the very few planets of that type known. A team of researchers used observations conducted with NASA’s TESS space telescope and detections obtained with the ESPRESSO and HARPS instruments to confirm its existence and obtain information on its characteristics. TOI-3261 b orbits in what is known as the Neptune desert precisely because it’s in an area where it’s very rare to find Neptune-type planets. For this reason, it will help to understand the evolution of certain types of planets.

The Sombrero Galaxy as seen in infrared by the James Webb Space Telescope

A new image (NASA, ESA, CSA, STScI) captured by the James Webb Space Telescope depicts the Sombrero Galaxy in infrared. The MIRI (Mid-Infrared Instrument) instrument offers details invisible to other telescopes, creating a portrait different from what astronomers are used to. The nucleus is very bright at visible light frequencies while in infrared a smooth inner disk is revealed. The outer disk is “clumpy” and this allows to understand the distribution of dust inside it, an important result to get an idea of ​​the ongoing star formation processes.

The WOH G64 star seen from the VLTI (ESO Image/K. Ohnaka et al.)

An article published in the journal “Astronomy & Astrophysics” reports the creation of a detailed image of the red supergiant star WOH G64 and its surroundings, the first ever obtained of a star outside the Milky Way. A team of researchers led by astrophysicist Keiichi Ohnaka of the Universidad Andrés Bello, Chile, used the GRAVITY instrument on ESO’s VLTI in Chile to obtain details of this star in the Large Magellanic Cloud. This study may provide important insights into a star that is going through the death throes that will end with its explosion as a supernova. A dust cocoon and a possible torus surrounding WOH G64 show signs of that death throes.