Super sharp image capturing Neptune from Earth

The Very Large Telescope (VLT) of the Southern European Observatory (ESO) has received the first light rays after activating the new adaptive optical mode . At this test, the glass captured Neptune, some star clusters and several other celestial bodies. The results are very impressive and a difficult thing to do with terrestrial observatories.

The previous MUSE tool, which operates in narrow wavelength observations with GALACSI optical modules, is now able to apply this new technology that adjusts the observation chaos as it looks through the turbulent atmosphere of the Earth.

From now on, the VLT from the ground has been able to see more clearly through optical wavelengths with images that are as sharp as NASA's Hubble Space Telescope flying in Earth orbit. MUSE's combination of state-of-the-art technology and wide viewing spectrum allows astronomers to observe celestial objects at a higher level of detail than before, thus analyzing their properties.

Picture 1 of Super sharp image capturing Neptune from Earth
The Neptune planet image is captured through the new technology being tested by the VLT glass using MUSE and GALACSI devices.Images taken from the surface of the Earth but have sharpness comparable to those taken in space by the Hubble Space Telescope.(Image: ESO / P. Weilbacher (AIP).

MUSE or Multi-Unit Spectrophotometer is a device attached to the VLT glass, it works with the GALACSI optical module and forms a Laser Star Navigation System or 4LGSF for short . MUSE is the first device to adopt this new technology and now has two optical modes to flexibly change, the wide-spectrum and narrow-spectrum observation mode.

Previously, MUSE devices observed over the wide spectrum of spectra with GALACSI could correct the effects caused by air turbulence above 1km above the glass, meaning a wide-angle field of view would be adjusted to no longer be affected by the turbulence of the air layer above.

But now, MUSE uses laser technology to accurately survey and correct the sky above to avoid the disturbance of the air, which creates sharper images than the public. The previous technology had eliminated the disturbances, but only in a small sky.

Picture 2 of Super sharp image capturing Neptune from Earth
Compare the picture of Neptune between shooting through the new adaptive optical mode and not shooting through it.(Image: ESO / P. Weilbacher (AIP)).

Picture 3 of Super sharp image capturing Neptune from Earth
Compare images of Neptune through the new VLT's adaptive optical mode and the Hubble Space Telescope.Note that the shooting time is different so the surface of the planet when facing to Earth and appearing in this image is also different.(Image: ESO / P. Weilbacher (AIP) / NASA, ESA, and MH Wong and J. Tollefson (UC Berkeley)).

With this technology, UT4 glass (one of the four glasses that make up the VLT glass system) with a glass mirror diameter of 8 meters, will reach the highest level of image theory and will not be blurred. due to the instability of air layers in the atmosphere.

Adaptive optics is a technique developed to balance and regulate the noise and blur caused by different layers of air movement in the Earth's atmosphere. Light from stars or distant objects will be distorted when its light passes through turbulent air layers, resulting in errors in the measurement results.

Picture 4 of Super sharp image capturing Neptune from Earth
Images of globular clusters NGC 6388 through the new adaptive optical mode of VLT.The image on the left is taken by the MUSE device through the wide spectrum without new technology, the middle image is the enlargement of an area in the left image, and the right image is the one taken by the device. MUSE is in a narrow spectral area but has new adaptive optical mode enabled.(Photo: ESO / S. Kammann (LJMU)).

In order for this technology to be implemented, a laser light column with orange light with a diameter of 30 cm straightens the sky and forms a false star, stimulating the atomic sodium in the atmosphere. The adaptive optical system will use this light to determine the atmospheric turbulence and calculate the correction thousands of times per second, thereby helping to stabilize the light received from the celestial body.

This new technology will be an important step to help engineers and astronomers in observing more clearly and analyzing more accurately the characteristics of celestial bodies. The first image taken is the image you are watching, and you know what you can expect from this technology.