Wednesday, 18 October, 2017

The Large Magellanic Cloud

Visible from the southern Hemisphere, the Large Magellanic Cloud is an Irregular type galaxy that has orbited around the Milky Way galaxy since shortly after its formation. The most recent data, though, has revealed that it seems to have a faded Barred Spiral structure. However, over time, the gravitational interactions with our galaxy caused it to become distorted, causing it to evolve into its current shape.

4dorado-large-magellanic-cloudThe Large Magellanic Cloud is about 160,000 light-years away from the Milky Way, making it the third closest galaxy to our own. It is roughly 14,000 light-years in diameter (compared to the approximately 100,000 light-year diameter of the Milky Way) and contains about 10 billion solar masses (about one percent of the mass of the Milky Way). These figures make it the fourth largest galaxy of our Local Group.

3tarantula nebulaBecause of the galaxy’s high gas content it is an active star forming galaxy, with the Tarantula Nebula (NGC 2070 or 30 Doradus) the most active region in our Local Group. Surveys of the galaxy have found roughly 60 globular clusters, 400 planetary nebulae, and 700 open clusters, along with hundreds of thousands of giant and supergiant stars.

The first recorded word of its position in the sky was noted by the Persian astronomer `Abd al-Rahman al-Sufi in the middle of the 10th century, but it was Ferdinand Magellan in 1519 that brought it into popularity through his writings, and for whom the Magellanic Clouds are named. While it is unclear what the future will hold, many scientists believe that the Milky Way will eventually consume the much smaller galaxy, along with its companion, the Small Magellanic Cloud.

Supernova 1987a (Honeycomb Nebula)

The brightest supernova which has    exploded in the current epoch is SN1987A or the Honeycomb Nebula, located at the edge of the Tarantula nebula, within the Large Magellanic Cloud. The explosion was seen on 23 February 1987, and since then the ejected material has created a set of ring structures. The outer ring is clearly visible in this image (right of centre). In the lower part of the image, an amazing structure is seen: the Honeycomb Nebula.

6ngc2074The Seahorse Nebula or NGC 2074 may look like a grazing seahorse, but the dark object toward the image right is actually a pillar of smoky dust about 20 light years long. This is a star forming region very near the expansive Tarantula Nebula. The energetic nebula is creating a star cluster, whose center is visible just off the top of the image in the direction of the neck of the seahorse. The representative color image was taken by the Hubble Space Telescope’s Wide Field Planetary Camera 2. As young stars in the cluster form, their light and winds will slowly erode the dust pillars away over the next million years.