New technology promises authentic images of the exoplanets in our neighbouring star system Alpha Centauri. The dress rehearsal immediately delivered something that makes astronomers dream of a great discovery.
We can all observe our solar system’s planets and dwarf planets with telescopes: Even the distant Pluto appears as a blurred sphere on the Hubble space telescope’s images.
But can today’s instruments also take pictures of planets orbiting other stars? We now know more than 4000 such exoplanets. But in most cases, they are far too far away to be seen next to their much brighter star. So far, it has only been achievable to infer their existence indirectly, for example, when the planets darken their lead a little or shake it minimally as they pass by.
The only exceptions here are some huge gas giants and planetary embryos, which peel off as bright lumps from dust disks. However, soon, there could also be images of smaller exoplanets, provided they are orbiting in a very close star system. At least that is the prospect of a new unique instrument that astronomers have connected to the Very Large Telescope (VLT) in Chile.
New Technology Promises: Hunt for a warm Neptune
The team used it to observe our neighbouring star system Alpha Centauri, four light-years away, for 100 hours, in which two suns orbit each other. With the NEAR instrument specially designed for this purpose, one can now track planets down to Neptune’s size in the habitable zone of Alpha Centauri A, writes the group around Kevin Wagner from the University of Arizona in “Nature Communications”.
The binary star system Alpha Centauri is visible in the night sky from the southern hemisphere. Therefore the four telescopes of the Very Large Telescope (VLT) of the European Southern Observatory in Chile can observe it excellently. Here you can see one of the interconnectable telescopes.
NEAR (New Earths in the AlphaCen Region) helps the Very Large Telescope search the area around the two Alpha Centauri stars for thermal radiation. To do this, the device hides one of the two suns every second and processes the data with a sophisticated computer program. According to the current publication, thanks to this technology, exoplanets that are ten times smaller than before can be detected in the system.
You can see a spot in the images that astronomers say might be a lukewarm planet. This world would, therefore be somewhat larger than Neptune and would not have a solid surface. The team emphasizes that it should exercise caution: the conspicuous pixels could just as quickly be just a meaningless image artefact of the innovative technology. Only further observations will show whether there is a planet at this point.
The three million US dollar NEAR project financed the Breakthrough Watch initiative, part of Russian-born billionaire Yuri Milner’s philanthropic activities. In recent years he has also launched other high-risk space projects, such as the “Breakthrough Starshot” initiative, which at some point plans to shoot tiny probes at Alpha Centauri.