Contact: Erik Arends
Born in the wild
Space Scoop: Astronomy News for Kids
The dwarf galaxy leaves a trail behind while rushing through a group of galaxies. In this trail, stars have managed to form. Astronomers zoomed in on the star that the arrows point to. They saw the star blowing out streams of gas with speeds of up to 160 kilometers per second.
Credit: NAOJ, CFHT, GALEX, Y. Ohyama & A. Hota
In the Milky Way – the galaxy in which we live – stars are born in a safe home, surrounded by protecting, soft, motionless clouds of gas. But how different is the situation in a small galaxy far away, at a distance of 55 million light years! This dwarf galaxy is currently flying through a group of galaxies with a staggering speed of 1,000 kilometres per second. During its flight, it is leaving behind a long trail of gas. And unlike in our Milky Way, the conditions in this trail are what you would call quite extreme. Temperatures reach up to an intense one million degrees and raging cyclone winds are blowing at a stunning speed of 4 million kilometres an hour.
Japanese astronomers have now discovered that, despite these wild circumstances, stars have managed to form inside this trail. This kind of star formation is unlike anything we've ever seen in the Milky Way. Apparently, some stars have found a way to form in such extreme environments. For stars from the relatively safe, rustic Milky Way, this would feel like being born on a rollercoaster ride inside an oven. Not exactly an ideal situation to give birth in!
While zooming in on one of these tough stars inside the trail, the Japanese found another astonishing fact: it was blowing out streams of gas at a speed of 160 kilometres per second. These extra-galactic stars are truly some wild, exotic fellows! Compared to them, our Sun is a softy!
This dwarf galaxy is racing through the so-called Virgo cluster. A cluster is a group of galaxies that belong together. Our own Milky Way is part of another cluster, called the Local Group.