ESO’s Very Large Telescope (VLT) has achieved first light with a new adaptive optics mode called laser tomography — and has captured remarkably sharp test images of the planet Neptune, star clusters and other objects.
The pioneering MUSE instrument in Narrow-Field Mode, working with the GALACSI adaptive optics module, can now use this new technique to correct for turbulence at different altitudes in the atmosphere. It is now possible to capture images from the ground at visible wavelengths that are sharper than those from the NASA/ESA Hubble Space Telescope. The combination of exquisite image sharpness and the spectroscopic capabilities of MUSE will enable astronomers to study the properties of astronomical objects in much greater detail than was possible before.
The MUSE (Multi Unit Spectroscopic Explorer) instrument on ESO’s Very Large Telescope (VLT) works with an adaptive optics unit called GALACSI. This makes use of the Laser Guide Star Facility, 4LGSF, a subsystem of the Adaptive Optics Facility (AOF). The AOF provides adaptive optics for instruments on the VLTs Unit Telescope 4 (UT4). MUSE was the first instrument to benefit from this new facility and it now has two adaptive optics modes — the Wide Field Mode and the Narrow Field Mode .
The MUSE Wide Field Mode coupled to GALACSI in ground-layer mode corrects for the effects of atmospheric turbulence up to one kilometre above the telescope over a comparatively wide field of view. But the new Narrow Field Mode using laser tomography corrects for almost all of the atmospheric turbulence above the telescope to create much sharper images, but over a smaller region of the sky .
With this new capability, the 8-metre UT4 reaches the theoretical limit of image sharpness and is no longer limited by atmospheric blur. This is extremely difficult to attain in the visible and gives images comparable in sharpness to those from the NASA/ESA Hubble Space Telescope. It will enable astronomers to study in unprecedented detail fascinating objects such as supermassive black holes at the centres of distant galaxies, jets from young stars, globular clusters, supernovae, planets and their satellites in the Solar System and much more.
Adaptive optics is a technique to compensate for the blurring effect of the Earth’s atmosphere, also known as astronomical seeing, which is a big problem faced by all ground-based telescopes. The same turbulence in the atmosphere that causes stars to twinkle to the naked eye results in blurred images of the Universe for large telescopes. Light from stars and galaxies becomes distorted as it passes through our atmosphere, and astronomers must use clever technology to improve image quality artificially.
To achieve this four brilliant lasers are fixed to UT4 that project columns of intense orange light 30 centimetres in diameter into the sky, stimulating sodium atoms high in the atmosphere and creating artificial Laser Guide Stars. Adaptive optics systems use the light from these “stars” to determine the turbulence in the atmosphere and calculate corrections one thousand times per second, commanding the thin, deformable secondary mirror of UT4 to constantly alter its shape, correcting for the distorted light.
MUSE is not the only instrument to benefit from the Adaptive Optics Facility. Another adaptive optics system, GRAAL, is already in use with the infrared camera HAWK-I. This will be followed in a few years by the powerful new instrument ERIS. Together these major developments in adaptive optics are enhancing the already powerful fleet of ESO telescopes, bringing the Universe into focus.
This new mode also constitutes a major step forward for the ESO’s Extremely Large Telescope, which will need Laser Tomography to reach its science goals. These results on UT4 with the AOF will help to bring ELT’s engineers and scientists closer to implementing similar adaptive optics technology on the 39-metre giant.
Learn more: Supersharp Images from New VLT Adaptive Optics
Check this out: 2019 Astronomer’s Guide to the Night Sky
The Latest on: Very Large Telescope
[google_news title=”” keyword=”Very Large Telescope” num_posts=”10″ blurb_length=”0″ show_thumb=”left”]
via Google News
The Latest on: Very Large Telescope
- Space mystery: James Webb Telescope captures impossible Milky Way-like Galaxy that 'shouldn't exist'on February 27, 2024 at 7:33 am
A “massive” ancient galaxy which “should not exist” has been spotted at the edge of the universe after a seven-year hunt by a team of astronomers. The galaxy – named ZF-UDS-7329 – was formed around 13 ...
- Metal scar found on cannibal staron February 26, 2024 at 8:01 am
Using ESO’s Very Large Telescope, astronomers found that the signature of these chemical elements changed periodically as the star rotated, as did the magnetic field. This indicates that the ...
- Brightest and fastest-growing: astronomers identify record-breaking quasaron February 22, 2024 at 9:42 am
Using ESO’s Very Large Telescope (VLT) in Chile, this quasar has been found to be the most luminous object known in the Universe to date. The supermassive black hole, seen here pulling in ...
- Brightest known object in the universe was hiding in plain sight for decades, researchers sayon February 21, 2024 at 3:13 pm
When astronomers spied a quasar called J0529-4351 using the European Southern Observatory’s Very Large Telescope, they discovered that the incredibly distant object is so far from our solar ...
- Scientists have found a black hole so large it eats the equivalent of one sun per dayon February 20, 2024 at 11:16 am
With a mass 17 billion times larger than our sun, this black hole is the fastest-growing black hole ever recorded, Australian National University said.
- Very Large Telescope snaps gorgeous shot of Milky Way's star-studded core (photo)on February 20, 2024 at 3:00 am
A new view from the European Southern Observatory's (ESO) Very Large Telescope (VLT) captures the abundant star-forming region at the center of the Milky Way. The VLT, located in Chile's Atacama ...
- Scientists have found a black hole so large it eats the equivalent of one sun per dayon February 20, 2024 at 2:54 am
and then confirmed it with the European Southern Observatory's Very Large Telescope, one of the largest telescopes in the world. Though black holes themselves don't emit any light, very large ones ...
- “Old Smoker” and the “Squalling Newborns”: Strange new star type discovered hiding in the Milky Wayon February 4, 2024 at 11:00 pm
That’s when then the team turned to the ESO’s aptly-named Very Large Telescope. And to the University of Valparaiso’s Dr Zhen Guo, who headed up the team’s work on the spectra, whose goal ...
- Which telescope will be 1st to find alien life? Scientists have some ideason February 2, 2024 at 8:00 am
A peek into the future of exoplanet science suggests the forthcoming European Extremely Large Telescope (ELT) is going to give us our best chance in the next two decades of detecting biosignatures on ...
via Bing News