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Elliptical Galaxy M87 (NGC 4486), type E1, in Virgo, together with other galaxies in the Virgo Cluster.

M87 is the dominant galaxy in the closest big cluster to us, the Virgo Cluster of galaxies, and lies at the distance of this cluster (about 60 million light-years).

M87's diameter of apparently about 7' corresponds to a linear extension of 120,000 light years, more than the diameter of our Milky Way's disk.  However, as M87 fills a much larger volume, it contains much more mass than our galaxy,  in the order of several trillion (10^12) solar masses.

M87 is famous for two peculiar features, a huge globular cluster system (not resolved in this image), and a spectacular jet - just visible in the top image to the top right of the core, but more apparent in the bottom, enlarged, image.

This giant jet extends thousands of light years (estimated 7-8,000) and consists of ejected gaseous material (high speed electrons) from the core of the galaxy.  This jet is powered by an object, probably a supermassive black hole at the centre of M87, which has the mass of three billion suns, but is concentrated into a space no larger than our solar system.

Image info

Telescope:  Celestron 9.25" Schimdt-Cassegrain at f/6.3

Focus:  Prime focus

Filter:  Celestron LPR

Mount:  Vixen GPD with Skysensor2000

Camera:  Modified Canon EOS 300D, at ISO400

Guiding:  700mm refractor guidescope, SAC7 camera, autoguided with Guidedog software

Exposure:  Total 87 mins (29 x 180s)

Date:  6th February 2005

Processing:  RAW file conversion, Offset and Dark subtraction, flat fielding, registering and stacking done in IRIS.  Curve stretching and colour saturation enhancement by Luminance Layering in Photoshop CS.




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