- Jonathan Amos
- Science Correspondent – BBC
Chameleon 1: ice buried in a thin (blue) molecular cloud
The new James Webb Space Telescope has penetrated deep into the ice depths of space.
Webb searched some of the darker, cooler regions of space to find clues about the chemistry that goes into making planets, and possibly even life.
This newly released image shows part of the Chameleon I molecular cloud, or Chameleon 1, about 630 light-years from Earth.
Here, at temperatures as low as about -260 degrees Celsius, the Webb telescope is detecting types of ice grains that have not been observed before.
Eventually, these clouds will collapse to form stars, with planets around them. The chemistry Webb detected will be incorporated into the formation of those planets.
You can see these objects in action in the upper left of the image.
The orange “Hourglass” is a protostar – a star in the making – that pulls material from the cloud into itself.
The orange stars below are more mature and bright enough to give birth to the distinctive six bulges now familiar in Webb’s images, made up of the telescope’s segmented mirror design.
But to discover the ice, the Webb telescope brushes all of these stars to the side and looks at the stars behind the delicate blue Chameleon 1.
When the light from these objects shines through the cloud, some of it is absorbed by the ice to form it.
“It’s kind of like a shadow puppet,” explained Dr Melissa McClure of Leiden University in the Netherlands.
She told BBC News: “You have a kind of shape that creates a shadow. The ice absorbs certain wavelengths of light, and you add it all up in a spectrum to see what chemical species you have.”
This work is mainly done on Webb’s telescope, with the near-infrared and mid-infrared spectroscope, and to some extent with the Near Infrared Camera (NIRCam) which produced the beautiful image at the top of the page.
In addition to simple ices, such as water, carbon dioxide, carbon monoxide, ammonia and methane, Webb sees many other compounds, including carbonyl sulfide and the more complex organic ice methanol. There are also hints of chemical species with multiple carbon atoms, such as acetone, ethanol, and acetaldehyde.
It’s easier for astronomers to see these targets in space when they’re gases, but Webb achieves a new feat by seeing them in a solid state, like ice.
This discovery will help scientists as they try to understand where the chemistry of life came from, and how it built the evolution it is now showing on our planet.
“Although we’ve discovered more ice than ever before, the amount of light elements (carbon, hydrogen, oxygen, nitrogen and sulfur) inside it is still less than we expect,” says Dr Helen Fraser, from the Open University in Britain.
“This is exciting for astronomers, because it means there’s something we don’t yet fully understand about interstellar chemistry, and that prompts us not only to keep observing, but also to experiment in the lab.”
Near a newly formed star, icy dust grains like those in Chameleon 1 would mostly evaporate, but moreover could remain solid and clump together to form comets.
“These comets will have a large chemical stock inside them, and they probably bombarded the planets (with this stock) certainly early in their history,” says Dr. Martin McCostra from Heriot-Watt University in Britain.
He told BBC News: “In the case of Earth, the belief today is that the lamb carried by comets was part of that organic soup from which life evolved.”
The Webb Space Telescope is a joint effort of the US, European and Canadian space agencies.
