ESO: Messier 100 — Grand Design Splendour

[bystander]

Messier 100 — Grand Design Splendour
ESO Picture of the Week | 2013 Jul 29

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Spiral galaxies are usually very aesthetically appealing objects, and never more so than when they appear face-on. And this image is a particularly splendid example: it is the grand design spiral galaxy Messier 100, located in the southern part of the constellation of Coma Berenices, and lying about 55 million light-years from Earth.

While Messier 100 shows very well defined spiral arms, it also displays the faintest of bar-like structures in the centre, which classifies this as type SAB. Although it is not easily spotted in the image, scientists have been able to confirm the bar’s existence by observing it in other wavelengths.

This very detailed image shows the main features expected in a galaxy of this type: huge clouds of hydrogen gas, glowing in red patches when they re-emit the energy absorbed from newly born, massive stars; the uniform brightness of older, yellowish stars near the centre; and black shreds of dust weaving through the arms of the galaxy.

Messier 100 is one of the brightest members of the Virgo Cluster, which is the closest cluster of galaxies to our galaxy, the Milky Way, containing over 2000 galaxies, including spirals, ellipticals, and irregulars. This picture is a combination of images from the FORS instrument on ESO’s Very Large Telescope at Paranal Observatory in Chile, taken with red (R), green (V) and blue (B) filters.

Credit: ESO

[Ann]

It is always nice to see a picture of M100, one of my favorite galaxies.

A good thing about this particular image is that it really brings out the high surface brightness of the lens, the area nearest the nucleus. The spiral arms are well-formed and elegant, but much fainter than the lens and nucleus.

http://www.eso.org/public/images/potw1330a/ wrote:

This very detailed image shows the main features expected in a galaxy of this type: huge clouds of hydrogen gas, glowing in red patches when they re-emit the energy absorbed from newly born, massive stars; the uniform brightness of older, yellowish stars near the centre; and black shreds of dust weaving through the arms of the galaxy.

Click to view full size image

Credit: J. Trauger, JPL and NASA/ESA

This is true, as far as it goes. Actually the uniformly yellow bulge is relatively faint. On the other hand, M100 has a very bright nuclear ring and a small, very bright nucleus.

Ann