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PLN 85 + 4.1
Merideth Beukelman

PLN 85+4.1

The distance to PLN 85 + 4.1 is estimated to be 3818 light-years away (estimated with ratios, using what is known about the Dumbbell Nebula); we find a maximum angular size of 132.31 arcseconds, which corresponds to a linear size of 2.45 light-years.

What you see in this picture is a planetary nebula. Planetary nebulae actually have nothing to do with planets, and only received the name because they appear to look like planets when observed with a small telescope. A planetary nebula is in fact a glowing cloud of gas, shed off from the outer layers of a dying low mass star. Intense ultraviolet radiation is emitted by the dying star and ionizes the surrounding dust and gas. The ionized dust and gas then emits the lovely colored light that we see in planetary nebulae.

The red color we see in this planetary nebula is evidence that the ionized gas is Hydrogen. Therefore, the low mass star was most likely young because as a star ages it gets heavier elements in its layers. When an older star dies, its planetary nebula is likely to have more variation in color than we see here because of the greater variety in elements. Hydrogen is the lightest of the elements, and the red Hydrogen gas is all we see in this image. Therefore, we can confidently conclude that this was a young star that died. We also know that the star must have been a low mass star because the death of a large mass star produces a supernova while the death of a loss mass star produces a planetary nebula.


Bennett, J., Donahue, M., Schneider, N., & Voit, M. (2007). The Essential Cosmic Perspective (sixth ed., p. 344). San Francisco, CA: Pearson Addison-Wesley.

Palen, S. E. (2002). Schaum's Outline of Theory and Problems of ASTRONOMY (p. 161). N.p.: The McGraw-Hill Companies, Inc.

Right Ascension (J2000) 20:32:24.65
Declination (J2000) +47:21:15.7
Filters used B (Blue), C (Clear), R (Red), V (Green)
Exposure time per filter B, V, R, and C (60s x 5)
Date observed October 12, 2011



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