Skip to Navigation | Skip to Content

Previous image Up to Astr111 Index Next image ASTR 212 Photography Projects, Spring 2015

Messier 88 (NGC 4501)
Zachariah James Watson

Messier 88

Introduction:

The entire universe is filled with more than we would could possibly comprehend and discover in our current liftime. Among the most beautiful and magnificant objects in the universe is Messier 88. M88/Messier 88 is a spiral galaxy that lies within the Coma Berenices constellation. It possesses an apparent magnitude of 9.6 and an angular diameter of 7 x 4 arc-minutes. It lies at an estimated distance of about 50-60 million light years. It was discovered by reknowned astronomer Charles Messier back in 1781. M88 is among one of the first of the 15 Messier objects that belong to the Virgo Cluster of galaxies. It is the 1401st object out of the 2096 galaxies that are members of that particular cluster.

Interpretation of colors & structures in Rehoboth image:

Messier 088

Image by Chris Spedden.

Within the bulge of M88, there is a mostly orange color, which could imply the presence of multiple stars that are older and cooler than other stars. This could also signify reddening due to the factor of dust extinction, which is much more likely than the first implication. The longer wavelengths of light (infrared light) are unaffected by dust while the other wavelengths of light (optical light) is scattered by dust. Each of these forms of light and their relationship/impact with dust affects how the appearance and colors of M88 has ultimately turned out.

Linear size & distance:

Distance=18.628 Mpc=18628 kpc

Size in light years=107,938.61 lyrs

Non-optical wavelength data &/or images:

M88 in Infrared; Spitzer

Red-poster M88.png

Stars with high temperatures emit ultraviolet light. When the light makes contact with dust, it is then absorbed by it. This absorbtion process causes it to rise in temperature, which then causes it to emit its own light within the infrared spectrum with wavelengths of about 12 to 100 microns. This collision of dust and light affects the amount of light emitted and the pattern of colors that emerge from the object. The dust temperature, dust surface density, and gas to dust ratio determine how the light and color will appear through a telescope. These measurements must be regularly adjusted to capture the desired pixel image.

Detailed Calculation/measurement:

d=18.628 Mpc= 18628kpc.

After calculating the distance of M88 as 18.628 Mega parsecs, I proceeded by translating it into 18628 kilo parsecs. Afterwards I moved forward by translating it into radians, arcseconds, and more kilo parsecs.

1 rad/206265 arc x 18628 kpc = 0.11 kpc/px

I then translated it into pixal values in order further translate it into arcseconds and radians.

Pixal Value = 301, (624, 233) - (458, 484)

355.18 arcsec / 206265 = 0.0017 rad

33.11 kpc x 1000 pc/1kpc x 3.26 lyrs/1pc = 107, 938.61 lyrs

After calculating and translating my measurements into kilo parsecs, parsecs, and light years, I came to the conclusion of 107, 938.61 light years.

Highest y value = 3505, x value = 0

This diagram was what ultimately allowed me to reach my final conclusion/light year value.

References:

http://www.calvin.edu/academic/phys/observatory/images/Astr212.Spring2013/Spedden.html

www.universe today.com/48102/messier-88/

http://astropixels.com/galaxies/M88-01.html

Table of image details:

Right Ascension (J2000) 12:32:00.00
Declination (J2000) +14:25:11.00
Filters used B (Blue), C (Clear), R (Red), V (Green)
Exposure time per filter B: 9 x 300 seconds, V: 5 x 300 seconds, R: 2 x 300 seconds, & C: 5 x 300 seconds
Image dimension 7×4 (arc min)
Date/time observed 3/30/2015 at 8:28 P.M.

Data Reduction:

Below is the process that I followed in order to analyze my data images.

I adjusteded the bias, dark, flat field, and cosmic rays to achieve the desired image of M88.

After accumulating my B, C, R, & V filters, I calibrated each one in order to complete my final calibrated LRGB image. Then I proceeded to complete my image with the following color filters.

The input of each color filter is as follows.

Red: 2.5

Green: 3.5

Blue: 30

Luminance Weight: 10%

These color adjustments for the balance, saturation, and gamma enabled me to finalize the image.

Afterwards, I cropped my image, decreasing its overall width and height from 1092 x 736 to 472 x 400. This is how I ended up with my final image calculation.

Special thanks to Chris Spedden and Jason Smolinski for their support in this endeavor. I couldn't have completed it without their help.

 

 

Secondary

Secondary content.

Sidebar

Side content.