Illustration of stars colliding. Image: agsandrew/Shutterstock
Astronomers have observed and photographed the distant sight of two stars colliding, resulting in a massive explosion.
Given the vastness of space, we tend to think of the idea of two stars colliding as something rare.
However, the opposite is the case in many examples, most recently seen by astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA), who have observed an incredible cosmic collision.
Located around 1,500 light years from Earth, the Orion Molecular Cloud 1 (OMC-1) is a dense and active star factory just behind the Orion Nebula, containing many protostars, or the ‘embryos’ of stars.
In a research paper published to the Astrophysical Journal, astronomers found that within this cloud of protostars, several latched onto each other gravitationally and gradually drew closer.
Eventually, two of these stars got a little too close and either grazed each other or collided.
This triggered an incredible eruption that launched other nearby protostars and hundreds of giant streamers of dust and gas into interstellar space, at speeds greater than 150km per second.
ALMA image of the OMC-1 cloud in Orion showing the explosive nature of star birth. Image: ALMA (ESO/NAOJ/NRAO), J Bally, B Saxton (NRAO/AUI/NSF)
Regulation of star formation
To put this into perspective, the amount of energy release during this single, massive event was equivalent to the amount of energy emitted by the sun during a 10m-year period.
Believed to have occurred around 500 years ago, such explosions are expected to be relatively short-lived, with the remnants lasting only centuries. They have now been captured in glorious detail.
Explaining their use in systems such as OMC-1, lead author of the paper, John Bally, said: “Though fleeting, protostellar explosions may be relatively common.
“By destroying their parent cloud, as we see in OMC-1, such explosions may also help to regulate the pace of star formation in these giant molecular clouds.”
Aside from providing an awe-inspiring image, the observations made by Bally and his team help to provide a greater understanding of the distribution and high-velocity motion of the carbon monoxide gas inside the streamers.
