geek learn science

Superbig clusters and supersmall stars: meet Laniakea and 2MASS J0523-1403

Laniakea means “immense heaven” in Hawaiian and is the name of the supercluster R. Brent Tully, Hélène Courtois, Yehuda Hoffman & Daniel Pomarède gave to this incredibly massive group of galaxies. the researchers published their conclusions in Nature in document doi:10.1038/nature13674. Usually clusters, or groups of galaxies, have dozens of galaxies, massive clusters have thousands of galaxies, but this supercluster has 100 000 galaxies in it.

Milky Way is at the end of one of the arms of Laniakea and is moving long with the Local Group towards the Great Attractor, a region at the center of Laniakea that pulls in thousands of galaxies towards it.

Laniakea has 500 million ly in diameter and contains the mass of one hundred million billion Suns spread across 100,000 galaxies according to

Now we know our address:
Earth, the third planet of Sol, our Solar System. Sol is at the edge of one of the two arms of Milky Way, which, in turn, is a member of Local Group. This Local Group is at the edge of one of the arms of Supercluster Laniakea.

Huge, way too huge.

Now, what about smaller things, like the smallest star ever detected? Phil Plait, from Slate Blogs, explains hwo such small stars exist and what they are. such a small star, one that could fit inside Jupiter is 2MASS J0523-1403:

This small star is not a brown dwarf, a failed star. It is indeed a working star, and a very old one that has only 2k degrees Celsius on its surface. With some luck such star could orbit a star like Sol and we would see an interesting display of grandor in our skies.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.