Extract from ABC News
Jets of blue gas blast out of a cloud of dust in a photo of a rare space object just released by the Hubble Space Telescope.
The image captures a phenomenon known as a Herbig-Haro object.
Snapped in the constellation of Orion, the object known as HH-111 is around 1,300 light years away from Earth.
So what are we seeing in this striking image?
A Herbig … what?
Essentially what you are looking at is the birth of a star system, explains astronomer Brad Tucker of the Australian National University.
"At the centre you have what we call a protostar — where gas from a previous star has been collapsing down into a new baby star," Dr Tucker explains.
The new object is rapidly spinning and as it does so, it shoots out a stream of ionised gas — gas that's so hot it's had all its electrons stripped off — from its north and south poles.
The gas moves out through clouds of dust in the stellar nursery.
As it moves further away, it starts to spread out in much the same way your breath does on a frosty morning, Dr Tucker explains.
"As this gas disperses into the neighbouring areas, it starts to mix and spread in the area and starts to create what we call a bow shock," he says.
"And that's why you get these nice kind of clear edges that we see at the end of this object."
So why is it so rare?
Despite being so spectacular, these objects are hard to spot.
For a start, they only hang around for 10,000–20,000 years.
The objects are not very bright because the dust absorbs much of their light, so we can only see them if they are nearby.
"We can't see them in other galaxies — you only see them in the Milky Way," Dr Tucker says.
And as for how rare they are? There's a hint in the numbers in their name.
"When their number is 111, there's not many of them," he adds.
How did we spot this one?
The image was captured by the Hubble Telescope's Wide Field Camera 3.
"The great thing about Hubble is that you can see things in both the visible light spectrum and the infrared spectrum," Dr Tucker says.
"So you kind of get this nice complete picture of what's going on."
While we can see the gas jet in the visible light, the infrared gives us more detail about the dust cloud.
"This is especially important for these objects; because it's a baby or forming star, they have lots of dust," Dr Tucker says.
Launched 31 years ago, the Hubble Space Telescope is coming to the end of its life and has recently had some equipment failures.
Its replacement, the James Webb telescope, is due to be launched in November or December this year.
This telescope will have greater infrared capacity than Hubble, but not as much visual ability.
That means an image of an object like HH-111 would look different than the one above, with even more detail in the dust clouds but less visual definition.
But Dr Tucker says optical images will be picked up eventually by other telescopes on the ground.
"We'll be able to see better in the optical colours than what Hubble can."
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