JWST Breaks New Ground - Twice
Between the orbit of Jupiter and Saturn lies a small 151Km wide asteroid/minor planet called Chariklo. This left over from our early solar system hasn't been imaged before, and was too small for JWST to image too, however, the JWST team were waiting for an opportunity to do some science.
Because of it's size, the only way they could do this was if a star passed directly behind the asteroid from the location of JWST, so it was put on a watch list, and in October, this is exactly what happened.
This is the first time any telescope has been able to see an object it wouldn't ordinarily be able to image, simply due to a chance occultation, so marks a first and interesting method for looking at some of these far off objects.
The asteroid happens also happens to sport a small ring of debris, and as the star didn't quite make a direct occultation, it did pass through the debris rings, being picked up twice as it passed through.
But what really was impressive was the second bit of data gathered, as the occultation occurred JWST was able to record the composition, detecting water ice.
Up until now, it had been assumed that the asteroid would have a significant water ice component, but this is the first time anybody has been able to take some real data from it.
Objects like Chariklo tell us so much about the early solar system, how Earth got it's water, and what other systems and exoplanets are likely made from.
