Jupiter’s moons Europa and Ganymede imaged by the Very Large Telescope (VLT) | Sorae Portal to space

How does the round object in this photo look to you? The object, which is a bit hazy but looks like a ball of polished marble, is actually a moon of Jupiter, photographed by a large ground-based telescope.Europahe is.

The video was captured at the Paranal Observatory in Chile, which is operated by the European Southern Observatory (ESO).Very Large Telescope (VLT)monitoring equipment“sphere”（※ 1）he is. It is created by coloring and synthesizing monochrome images obtained with infrared filters (two wavelengths of 2.11 μm and 2.251 μm) in yellow and blue depending on the wavelength.

SPHERE is another satellite that doesn’t just orbit EuropeGanymedeAlso caught shows the following image Ganymede created based on the image acquired by SPHERE. Europa’s diameter is second only to Earth’s moon3121 kmBut Ganymede’s diameter is larger than that of Mercury5268kmThere are also two moons due to interactions with Jupiter and other moonstidal heating（※ 2）It became a source of heat and filled liquid water under the ice crust covering the surface.inland seaIt is believed to exist.

[لوحظ قمر كوكب المشتري جانيميد في الأطوال الموجية للأشعة تحت الحمراء بواسطة التلسكوب الكبير جدًا التابع للمرصد الأوروبي الجنوبي (VLT) (Credit: ESO / King & Fletcher)]

From the University of Leicester (UK)Mr. Oliver KingWhenLee in FletcherUse SPHERE observation data to analyze chemical species present on Europa and Ganymede surfaces, and summarize them in two papers. SPHERE observations of the VLT were made for Europa in December 2014, Ganymede in February 2015 and July and September 2021.

Ganymede’s surface in visible light isA relatively new and bright areaWhen,ancient dark worldAccording to ESO, King and Fletcher are located on the surface of Ganymede.bright areaMainlywater icedifferent types ofa little saltIt is said that it was discovered that all of them were included. On the other hand, the composition of the dark areas remains a mystery.

[▲ الصورة المرجعية: Europa (يسار) و Ganymede (يمين) تم التقاطها بواسطة مركبة الفضاء Juno التابعة لناسا (الائتمان: يسار: NASA / SwRI / MSSS / Thomas Appéré ، إلى اليمين: NASA / JPL-Caltech / SwRI / MSSS / Kevin M. Gill) ]

Observing Jupiter’s moons from Earth is not an easy task. According to ESO, the apparent size of Europa and Ganymede as seen from Earth is a 1 euro coin (23.25 mm in diameter) placed 3 to 5 kilometers apart. Additionally, the image is blurred due to the effects of atmospheric turbulence.

Therefore, the VLT cancels out the effects of weather fluctuations.Compensation opticsUsing the AO (adaptive optics) technology, we achieved observations with a resolution comparable to that of a space telescope. Adaptive optics are used in large telescopes around the world, including the VLT and the Subaru Telescope at the National Astronomical Observatory of Japan’s Hawaiian Observatory.

Connection:It’s as clear as Hubble even though it’s taken from Earth. Image of Neptune using “adaptive optics”

Europa and Ganymede images captured by VLT’s SPHERE were published by ESO on October 10, 2022.

*1: An acronym for REsearch.
*2: A phenomenon in which the interior of a celestial body is distorted and heated by the tidal force caused by the gravity of another celestial body.

Connection:Jupiter and Europa taken by the James Webb Space Telescope during its commissioning

source

• Image Credit: ESO / King & Fletcher
• it’s a Jupiter’s icy moons
• King et al. Compositional Mapping of Europe Using MCMC Modeling Near IR VLT/SPHERE and Galileo/NIMS Observations (The Planetary Science Journal)
• King et al. – Global Ganymede surface composition modeling: near-infrared mapping from VLT/SPHERE (arXiv)

Text / Matsumura Takehiro