Astronomy Picture of the Day: 01/08/14 - NGC 2170

NGC 2170 is a spectacular nebular region located in the constellation Monoceros. Part of this beauty lies in the fact that it is a region bearing many different types of nebulae. We have a reflection nebula that is surrounded by other blueish reflection nebulae, black absorption nebulae and a red emission region. Areas such as this tend to be hot beds for star formation activity, which gives us plenty of eye candy to look at.

Speaking of star formation activity; this region lies on the edge of a molecular cloud, which is known as Mon R2. It can be found close in the sky to the Orion nebula, but it is currently estimated to be almost twice as far away (making it around 2,400 light-years from Earth).

NGC 2170 is thought to span about 80 light-years across. Just to give you a sense of how incredibly large this is, our solar system is sometimes estimated to be about 15 light-hours across (one light year extends 9.5 trillion kilometers [or about 6 trillion miles]) The distance that separates our solar system from our closest neighbor (in the Alpha Centauri star system) is about 4.37 light-years. That number only says how long it would take a photon traveling from the sun at the speed of light to reach it, not a space ship or one of the voyager probes (it would take thousands of years to journey to the closest star, Proxima Centauri, going at top speed). In this stellar nebula, it takes light 80 YEARS to travel from one side to the other. Very large indeed!

Sources & Further Reading: http://www.fromquarkstoquasars.com/apod-ngc-2170/

Image Credit: Adam Block, Mt. Lemmon SkyCenter, U. Arizona

Astronomy Picture of the Day: 12/02/13 - NGC 6914

This lovely area is NGC 6914, which is located more than 6,000 light-years away in the constellation by the name of Cygnus. (It can be found near the plane of our Milky Way galaxy)

The complex star-forming region has two designated nebulae. First, we have an emission nebula (seen in the pinkish-red areas), which are created when young stars spew large quantities of ultraviolet radiation into their surrounding environment. This ultraviolet radiation excites the hydrogen gas molecules, causing them to become ionized. In turn, this ionization is responsible for powering the nebula, allowing them to glow brilliantly.

Secondly, we have a reflection nebula, which is depicted in blue. Nebulae of this type are created when light from embedded stars bounce off of tiny grains of interstellar dust. This causes the light to scatter about. Nebulae such as this tend to be blue, as the bluer end of the electromagnetic spectrum scatters light more effectively than red.

Sources & Further Reading: http://www.fromquarkstoquasars.com/astronomy-picture-of-the-day-120213-ngc-6914/

Image Credit: Descubre Foundation, CAHA, OAUV, DSA, Vicent Peris (OAUV), Jack Harvey (SSRO), Juan Conejero (PixInsight)