My homeland is a winter wonderland with snow everywhere by now. Many inland water bodies have frozen and the sea ice forms in the shallow Baltic Sea. You can also see streaks of clouds over the sea heading towards the coast and bringing fresh snow there. My mom was a toddler on the island of Saaremaa (left) where there is a well-preserved meteor crater. Coincidence.
Source: NASA Terra-MODIS satellite image (Jan 15, 2021). MODIS = Moderate Resolution Imaging Spectroradiometer, the instrument on the Terra satellite which orbits around the Earth timed so that it passes from north to south across the equator in the morning. Terra MODIS views the entire Earth’s surface every 1 to 2 days, acquiring data in 36 spectral bands, or groups of wavelengths. It was designed to capture atmospheric, land, and ocean imaging in a single instrument. It uses a continuously rotating double-sided scan mirror to scan ±55-degrees and direct energy to four refractive objective assemblies; one for each of the VIS, NIR, SWIR/MWIR and LWIR spectral regions to cover a total spectral range of 0.4 to 14.4 µm. A high-performance passive radiative cooler provides cooling to 83K for the 20 infrared spectral bands on two HgCdTe Focal Plane Assemblies. Novel photodiode-silicon readout technology for the visible and near infrared provide unsurpassed quantum efficiency and low-noise readout with exceptional dynamic range.
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