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Messier 51 (NGC 5194)
Ben Minnema

Whirlpool Galaxy

Messier 51 or NGC 5194 is a spiral galaxy located in the constelation Canes Venatici. It can be seen by the eastern most stars of the Big Dipper. It is located 23 million light years away and has a size of about 35 percent that of the Milky Way. It was discovered in 1773 by Charles Messier, and its companion was discovered in 1781 by Pierre Méchain.This galaxy is set apart from other ones due to its interaction with the smaller galaxy as seen in the picture. It is actually merging with the smaller galaxy. The larger galaxy is "eating" the smaller galaxy. In other words the gravity of the larger one is pulling apart the smaller one, and eventually the larger one will consume all of the matter in the smaller.

This picture shows the areas of new star formation in the arms of the galaxy. The blue indicates hot star clusters. The picture also shows the two dense, bright cores of both the companion and the galaxy.The bright yellow core shows an older generation of stellar population. We can also see a streak of dust covering the companion, which blocks out some of the light.


Whirpool galaxy before and after supernova

There have been an abundance of supernovas in the whirpool galaxy of late. In a 17 year span there were three supernovas. A supernova is a stellar explosion when a star comes to the end of its life. These explosions can spew material off of the star at speeds up to 10 percent of the speed of light. These are rare because they only happen at the end of a star's very long life. Above is shown the supernova that happened in May of 2011.

Other Wavelength Picture

Whirlpool Galaxy

NASA/CXC/Wesleyan Univ./R.Kilgard, et al; Optical: NASA/STScI

This X-ray image of the Whirlpool Galaxy comes from the Chandra X-Ray telsescope. It shows multiple points of light that come from supernovas. These points of light are either neutron stars or black holes scattered about the galaxy. As we look to the center of both the galaxy and the companion, we can see very bright points of X-ray light. This shows the massive black holes that are at the center of both of these galaxies. The fuzzy intermittent light comes from superheated gas that is blown out from supernovas.

Table of Picture:

Right Ascension (J2000) 13:29;52
Declination 47:11:43
Filters used B (Blue) 45 x 90s, C (Clear) 4 x 90s, R (Red)8 x 90s, V (Green) 7 x 90s
Measured Linear Size* 58,680 light years
Actual Linear Size 60,000 light years
Distance 23,160,000 ly
Date/time observed

March 21, 2015

*In order to measure the linear size we used the Pythagorean theorem. Since we knew the distance to the galaxy, from the internet, we were able to determine the value distance-wise of each pixel. Knowing how many pixels across the galaxy was and the distance to the galaxy we were able to calculate its linear size.In order to calculate its distance in the first place they would have used different steps in the distance ladder.

See for distance ladder.

Color Balancing:

In order to create the final picture at the top of the page we had to go through many steps. First we took pictures with the Rehoboth telescope with different filters. Once we had those we could layer each picture of the same filter on top of each other. Then we put it into a program to layer all four combined pictures into one final combined picture. We then had to play with the values of how much of each color we wanted (See below for my values) and a luminance weight. We then had to run it through another program to make it jpeg compatible (hence the gamma value).

Red: 1 Green: 1.5 Blue: 7

Lumanance weight : 15%

Gamma Value: 1.1


Kilgard, R. "M51: Chandra Captures Galaxy Sparkling in X-rays." NASA, n.d. Web. 4 May 2015.

Howell, Elizabeth. "Whirlpool Galaxy: Exploding with Supernovas." N.p., 15 Apr. 2014. Web. 14 May 2015.

"Whirlpool Galaxy." N.p., 13 Apr. 2015. Web. 4 May 2015.



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