European Southern Observatory | MUSE | 2014 Nov 10
The new MUSE instrument on ESO’s Very Large Telescope (VLT) has provided researchers with the best view yet of a spectacular cosmic crash. The new observations reveal for the first time the motion of gas as it is ripped out of the galaxy ESO 137-001 as it ploughs at high speed into a vast galaxy cluster. The results are the key to the solution of a long-standing mystery — why star formation switches off in galaxy clusters.MUSE view of the ram-pressure stripped galaxy ESO 137-001
In image 1 the colours show the motions of the gas filaments — red means the
material is moving away from Earth compared to the galaxy and blue that it is
approaching. Image 2 is in close-to-natural colours, with the red patches being
glowing clouds of hydrogen gas. (Credit: ESO/M. Fumagalli)
A team of researchers led by Michele Fumagalli from the Extragalactic Astronomy Group and the Institute for Computational Cosmology at Durham University, were among the first to use ESO’s Multi Unit Spectroscopic Explorer (MUSE) instrument on the VLT. Observing ESO 137-001 — a spiral galaxy 200 million light-years away in the southern constellation of Triangulum Australe (The Southern Triangle) — they were able to get the best view so far of exactly what is happening to the galaxy as it hurtles into the Norma Cluster.
MUSE gives astronomers not just a picture, but provides a spectrum — or a band of colours — for each pixel in the frame. With this instrument researchers collect about 90 000 spectra every time they look at an object, and thereby record a staggeringly detailed map of the motions and other properties of the observed objects.
ESO 137-001 is being robbed of its raw materials by a process called ram-pressure stripping, which happens when an object moves at high speed through a liquid or gas. This is similar to how air blows a dog’s hair back when it sticks its head out of the window of a moving car. In this case the gas is part of the vast cloud of very thin hot gas that is enveloping the galaxy cluster into which ESO 137-001 is falling at several million kilometres per hour. ...
MUSE sneaks a peek at extreme ram-pressure stripping events.
I. A kinematic study of the archetypal galaxy ESO137-001 - Michele Fumagalli et al
- arXiv.org > astro-ph > arXiv:1407.7527 > 28 Jul 2014 (v1), 06 Oct 2014 (v2)
http://asterisk.apod.com/viewtopic.php?t=33040
http://asterisk.apod.com/viewtopic.php?t=33461
