The VLT observatory received super-accurate photographs of Neptune, which are not inferior in quality to the Hubble images, using artificial “laser” stars. These images and scientific data were published on the site of the European Southern Observatory.
“Hubble” and many other orbital telescopes have rather modest dimensions by the standards of terrestrial observatories, but they can get much sharper images of distant planets, galaxies and stars.
The reason for this is very simple – even the cleanest and rarefied air of the mountains, where the world’s largest optical telescopes are built, contains a lot of dust, microbes and other particles that scatter light.
For a long time scientists believed that this interference can not be destroyed, because of which the construction of large telescopes with a mirror, whose diameter is several tens of meters, was considered an absolutely waste of money.
At the turn of the century, physicists discovered that this problem can be solved by observing not the real, but fictitious stars in the night sky, which are “drawn” on it with the help of laser beams with a clearly defined wavelength and other properties.
Such lasers, as the scientific team of the VLT telescope explains, interact with certain atoms in the upper layers of the Earth’s atmosphere and make them shine that makes them look like stars. Observing them with the help of the same telescopes, one can write down the “pure noise” generated by the atmosphere and remove it from the data of real observations.
The first instruments of this kind began to be used in practice much later, in the middle of the last decade. Only two years ago, VLT received a similar laser “gun,” and now scientists have completed its full adjustment and correction on the last of the four modules of the telescope.
Its work was checked by astronomers, having received new super-succinct photos of Neptune – a planet remote from us by 4.3 billion kilometers. Its appearance remained a mystery to scientists before the Voyager 2 probe approached it in 1989, and before the launch of Hubble in 1992, which managed to open the almost invisible rings of Neptune.
These photos, as the researchers admit, are unlikely to disclose any new secrets of the eighth planet of the solar system. On the other hand, they say that laser “stars” cope with the task assigned to them, and that now VLT can be used for detailed observations of the chemical composition and other properties of the closest exoplanets.