Using the Hubble Space Telescope, astronomers have witnessed an infant star 20 times larger than the sun setting interstellar clouds ablaze. The source of this cosmic conflagration is a stellar jet travelling at an incredible 2.2 million miles per hour (3.5 million kilometers per hour), the fastest outflow of this type ever seen.
This particular outflow is also the longest outflow from a forming star or protostar ever seen by astronomers, stretching out for a staggering 32 light-years. For context, that is around 8 to 10 times as wide as our entire solar system.
The star illuminating them is IRAS 18162-2048, located around 5,500 light-years away, and the most massive protostar in the entire molecular cloud known as L291.
Protostars like IRAS 18162-2048 are fed by gas that falls to them from the surrounding clouds of gas and dust that originally condensed to form them. This matter can’t fall directly to these hungry cosmic infants because it still possesses angular momentum. That means it forms a swirling cloud around the protostar called an accretion disk, which gradually feeds this stellar newborn like a baby bottle.
However, just as human infants are pretty messy, so too are protostars. Powerful magnetic fields channel plasma in accretion disks to the poles of protostars, accelerating it to high-speeds and then blasting it out as jets.
HH objects are created when jets of ionized gas, or plasma, are blasted away from protostars at incredible speeds. These jets strike previously ejected gas, creating shockwaves that heat that gas, causing the bright glows demonstrated by HH 80 and HH 81 in this Hubble image.
First observed by Hubble in 1995, HH 80 and HH 81 are striking examples of HH objects not just due to the size and speed of the jet powering them, but also because this is the only jet astronomers have ever seen being driven by a young massive star and not a young low mass star.
This spectacular image of HH 80 and HH 81 and its capability to allow astronomers to study minute changes in the structure of these incredible cosmic bodies, was only possible thanks to the sensitivity and resolution of Hubble’s Wide Field Camera 3.
Thus, this image is further evidence that even after 36 years in service, Hubble is still a vital tool for astronomers.
