Found Images: 2023 March

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M44
http://www.astrosurf.com/ilizaso/orriak ... Q_U16m.htm
Copyright: Iñaki Lizaso

M44.jpg

[bystander]

A Legendary Nebula
NOIRLab Image of the Week | 2023 Mar 15

Image Credit: KPNO/NOIRLab/NSF/AURA

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The nebula that keeps on giving, Messier 1 (Crab Nebula) is captured here by the Nicholas U. Mayall 4-meter Telescope from Kitt Peak National Observatory (KPNO), a Program of NSF’s NOIRLab. The storied history of this supernova remnant in modern astronomy begins when it was recorded in 1731 by British astronomer John Bevis, who believed it was nothing more than a cloudy blob. It was more than three decades later that French comet hunter Charles Messier clarified that the object was in fact something, and it became the first entry in his catalog of nebulae and star clusters. Then in the early 20th century astronomers connected Messier 1 to a supernova explosion observed by Chinese astronomers in 1054. This made the Crab Nebula the first astronomical object to be connected to a previously observed supernova.

A pulsar — the ultra-dense, rapidly spinning remnant of a star — inside the Crab Nebula was discovered in 1968 at radio wavelengths. Its presence in the optical part of the spectrum was confirmed a year later by Americans John Cocke and Donald Taylor and British astronomer Michael Disney using the UArizona 0.9-meter Spacewatch Telescope at KPNO. The Crab Pulsar then became integral in advancing scientific understanding of supernova remnants: it was the first of its kind to link a historical supernova to a pulsar whose precise age is known.

This image was the last taken with the Mayall telescope before the Dark Energy Spectroscopic Instrument (DESI) was installed. The Crab Nebula was also the first target for the telescope’s first light in 1973.

[bystander]

Almost Touching
ESO Picture of the Week | SEST | 2023 Mar 20

Image Credit: ESO/A. Ghizzi Panizza (albertoghizzipanizza.com)

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This Picture of the Week shows a beautiful meeting between the Swedish–ESO Submillimetre Telescope (SEST) and the Milky Way, apparently almost touching each other. This shot was taken at ESO’s La Silla Observatory, located on the outskirts of the Chilean Atacama Desert, at an altitude of 2400 metres.

Light and darkness shape the Milky Way as it stretches across the night sky. The dark patches are dust clouds blocking the light behind them, coming from millions of stars in the central region of our galaxy.

SEST was built on behalf of the Swedish Natural Science Research Council (NFR) and ESO in 1987. It is a 15-m radio telescope, and it was the only large sub-millimetre telescope in the southern hemisphere at the time of first light. In 2003, the telescope was decommissioned as it was superseded by the Atacama Pathfinder EXperiment telescope (APEX) and the Atacama Large Millimeter / submillimeter Array (ALMA) further north in Chile. Over the years SEST has observed a wide range of astronomical objects, from comets to stellar nurseries and galaxies.

[bystander]

Portrait of a Galactic Jellyfish
ESA Hubble Picture of the Week | 2023 Mar 20

A thin spiral galaxy is seen edge-on in the lower right. Its bulge and arms are very bright, mixing reddish and bluish light. Patchy blue trails extend below it, resembling tentacles, made from star-forming regions. Six small, reddish elliptical galaxies are scattered. A very large elliptical galaxy with two cores sits by the top of the frame.

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Image Credit: ESA/Hubble & NASA, M. Gullieuszik and the GASP team

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The galaxy JW100 features prominently in this image from the NASA/ESA Hubble Space Telescope, with streams of star-forming gas dripping from the disc of the galaxy like streaks of fresh paint. These tendrils of bright gas are formed by a process called ram pressure stripping, and their resemblance to dangling tentacles has led astronomers to refer to JW100 as a ‘jellyfish’ galaxy. It is located in the constellation Pegasus, over 800 million light-years away.

Ram pressure stripping occurs when galaxies encounter the diffuse gas that pervades galaxy clusters. As galaxies plough through this tenuous gas it acts like a headwind, stripping gas and dust from the galaxy and creating the trailing streamers that prominently adorn JW100. The bright elliptical patches in the image are other galaxies in the cluster that hosts JW100.

As well as JW100’s bright tendrils, this image also contains a remarkably bright area of diffuse light towards the top of this image which contains two bright blotches at its core. This is the core of IC 5338, the brightest galaxy in the galaxy cluster, known as a cD galaxy. It’s not unusual for cD galaxies to exhibit multiple nuclei, as they are thought to grow by consuming smaller galaxies, the nuclei of which can take a long time to be absorbed. The bright points of light studding its outer fringes are a rich population of globular clusters.

This observation took advantage of the capabilities of Hubble’s Wide Field Camera 3 (WFC3), and is part of a sequence of observations designed to explore star formation in the tendrils of jellyfish galaxies. These tendrils represent star formation under extreme conditions, and could help astronomers understand the process of star formation elsewhere in the universe.

UV and Hα HST Observations of Six GASP Jellyfish Galaxies ~ Marco Gullieuszik et al

• Astrophysical Journal 945(1):54 (2023 Mar 01) DOI: 10.3847/1538-4357/acb59b
• arXiv > astro-ph > arXiv:2301.08279 > 19 Jan 2023

HST Imaging of Star-Forming Clumps in Six Gasp Ram-Pressure Stripped Galaxies ~ Eric Giunchi et al

• arXiv > astro-ph > arXiv:2302.10615 > 21 Feb 2023