Astronomers have spotted two monster stars about to merge in a stunning event that could reveal, for the first time, how supermassive stars are born.
A Spanish team reported the eclipsing of a star system, known as MY Camelopardalis, when they saw two huge stars circle in a very close orbit.
The star system is nestled within a small open star cluster, named Alicante 1, located about 13,000 light-years from Earth.
Our sun is a relatively rare star in its isolation. Most of the stars in our galaxy have been formed in binary or multiple systems, some of which are ‘eclipsing’.
Currently, the stars in My Cam are moving around each other at speeds of 621,000 miles (1 million km) per hour and are estimated to be no more than two million years old.
Each has a radius around 700 times bigger than the Earth's, but turns on itself at about the same time.
By watching the two stars with the 7.2ft (2.2 metre) telescope at the Calar Alto Observatory, researchers were able to find out the temperature and shape of each of the stars.
The stars, which each have 38 and 32 times the mass of our sun, are also thought to complete orbits of each other in under 1.2 days.
This means that their outer atmospheres are already touching and interacting, and are so close to each other that scientists believe they will eventually merge into one.
The resulting star is estimated to have at least 60 times the mass of the sun, according to the study by the University of Alicante.
HALF OF UNIVERSE'S STARS ARE ORPHANS WITH NO GALAXY
You can call them celestial orphans, stars flung out of their galaxies in colossal collisions that have occurred in space for billions of years.
These forsaken stars may be far more common than anyone ever realised.
New observations from suborbital rocket launches and an orbiting observatory show that as many as half the stars in the universe may be this kind, scientists said in November.
They found that the dim light these stars produce from the far reaches of the cosmos equals the amount coming from all the galaxies.
The data was collected during 2010 and 2012 flights of a Nasa suborbital rocket with the Cosmic Infrared Background Experiment (Ciber) measuring background fluctuations in a compilation of all the light emitted by stars and galaxies in the universe's history.
The researchers then checked the findings using Spitzer Space Telescope, an orbiting infrared observatory. The data indicated huge numbers of orphan stars, previously undetected, populate what had been thought to be the dark spaces between galaxies.
So how did billions of stars become orphans? Violently, to say the least.
Galaxies like our Milky Way are made up of stars, dust and dark matter bound together by gravity. As galaxies drift through space, they periodically crash into each other.
Stars and the other galactic stuff can merge together in these mash-ups, but some stars that were born and resided in these galaxies are stripped away and cast as debris into the cosmic wilderness.
The phenomenon of the orphan star has been well known. Astronomers have witnessed tidal streams of stars being stripped away from colliding pairs of galaxies.
Scientists are unsure what will happen next, but any merger is likely to be rapid and explosive, releasing massive amounts of energy.
While it won’t create a ‘hypergiant’ star, astrophysicists hope that by seeing the merger of such close binary stars, they can better explain how extremely massive stars form.
Hypergiants may be 100 or more times more massive than the sun, and emit hundreds of thousands of times more energy.
Although extreme stars such as these are believed to have been common in the early universe, today they are extremely rare - the entire Milky Way galaxy contains only a handful.
