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Hubble Space Telescope Spots the Farthest Known Star (engadget.com)
Researchers using Hubble space telescope data have spotted Icarus (aka MACS J1149+2223 Lensed Star 1), a blue supergiant whose light was emitted when it was 9 billion light years away from Earth -- over 100 times farther than the previous record-setter. According to Engadget, "They captured the star thanks to a rare, ideal gravitational lensing effect where the star's light was magnified not only by the gravity of an in-between galaxy cluster 5 billion light years from Earth, but by a star inside that cluster." From the report: Observers had been keeping close watch on the cluster since 2014, when they'd detected a supernova that turned out to be present in a galaxy 9 billion light years away. They realized Icarus was present in April 2016, when a point of light near the supernova seemed to change brightness. Don't get too attached to this new discovery. With this kind of distance, Icarus has long-since turned into a neutron star or black hole. The findings are still advancing science in ways you might not expect, however. As the Guardian noted, the Icarus study ruled out a theory that dark matter consists of black holes. If that had been the case, they would have brightened Icarus even more. And if nothing else, this proves that humanity can detect more than just the largest and brightest celestial objects at these kinds of distances.
I'd forget about that James Webb Telescope if I were you. This current administration is trying to kill it, but don't trust me, go look it up.
If it ever launches.
It's better to thoroughly test it while it's still on the ground . . . instead of having to send up a Geek Squad repair crew on the Space Shuttle, like we had to do with the Hubble.
Oh, yeah . . . we don't have the Space Shuttle anymore.
If there's trouble with the Webb, we'll have to politely ask our good friends the Russians for help.
Or maybe the Chinese.
Has India done any manned flight yet . . . ?
Schroedinger's Brexit: The UK is both in and out of the EU at the same time!
If that old thing can see something so unique and far away
I still don't understand how they can determine distances of such far-out objects. Yes I am aware of standard candles, and that we "know" how far away they are based on observed brightness. But observed brightness isn't just impacted by distance, it is also impacted by the size of the object. So how can we be so sure that these standard candles are not bigger or smaller than we assume they are?
Are the distances simply so large, that a standard candle would need to be exponentially larger/smaller than our assumed size in order to significantly impact the calculated distance?
Standard candles are things that have a fixed total brightness (or at least a brightness that we can work out independent of their size).
For instance a certain type of supernova is believed to happen when a white dwarf star, slowly accreting matter from a companion, finally gets too massive to support itself and collapses into a neutron star. Regardless of the mass of the original white dwarf, this mass at which this collapse happens is pretty much the same, and so the total brightness of this type of supernova is more or less constant.