star formation tagged posts

This is the “South Pillar” region of the star-forming region called the Carina Nebula. Like cracking open a watermelon and finding its seeds, the infrared telescope “busted open” this murky cloud to reveal star embryos tucked inside finger-like pillars of thick dust. Credit: NASA

A type of gas found in the voids between galaxies – atomic gas – appears to be part of the star formation process under certain conditions. The findings overturn a long-standing theory about the conditions needed for star formation to take place – a process that happens when dense clouds of dust and gas inside galaxies collapse.

It was previously thought that stars could form only in the presence of a different type of gas – called molecular gas. Atomic gas is composed of individual H atoms...

DI Cha star system. Image credit: ESA/Hubble & NASA, Acknowledgement: Judy Schmidt Text credit: European Space Agency

Star system is DI Cha, and while only 2 stars are apparent, it is actually a quadruple system containing 2 sets of binary stars. As this is a relatively young star system it is surrounded by dust. The young stars are molding the dust into a wispy wrap. The host of this alluring interaction between dust and star is the Chamaeleon I dark cloud — 1 of 3 such clouds that comprise a large star-forming region known as the Chamaeleon Complex. DI Cha’s juvenility is not remarkable within this region...

Figure 1: Example of a galaxy merger Credit: NASA, ESA, the Hubble Heritage Team (STScI/AURA)-ESA/Hubble Collaboration and A. Evans (University of Virginia, Charlottesville/NRAO/Stony Brook University)

The majority of stars have been believed to lie on a “main sequence,” where the larger a galaxy’s mass, the higher its efficiency to form new stars. However, every now and then a galaxy will display a burst of newly-formed stars that shine brighter than the rest. A collision between 2 large galaxies is usually the cause of such starburst phases, where the cold gas residing in the giant molecular clouds becomes the fuel for sustaining such high rates of star formation.

The question astronomers have been asking is whether such starbursts in the early universe were the result of having an overa...