Wednesday, November 19, 2014
Published on Nov 15, 2014 James Tyrwhitt-Drake
"A timelapse of Earth in 4K resolution, as imaged by the geostationary Elektro-L weather satellite, from May 15th to May 19th, 2011. Elektro-L is located ~40,000 km above the Indian ocean, and it orbits at a speed that causes it to remain over the same spot as the Earth rotates. The satellite creates a 121 megapixel image (11136x11136 pixels) every 30 minutes with visible and infrared light wavelengths. The images were edited to adjust levels and change the infrared channel from orange to green to show vegetation more naturally. The images were resized by 50%, misalignments between frames were manually corrected, and image artifacts that occurred when the camera was facing towards the sun were partially corrected. The images were interpolated by a factor of 20 to create a smooth animation. The animation was rendered in the Youtube 4K UHD resolution of 3840x2160. An original animation file with a resolution of (5568x5568) is available on request.
To answer frequently asked questions; why are city lights, the Sun, and other stars not visible? City lights are not visible because they are thousands of times less bright than the reflection of sunlight off the Earth. If the camera was sensitive enough to detect city lights, the Earth would be overexposed. The Sun is not visible due to mechanisms used to protect the camera CCD from direct exposure to sunlight. A circular mask on the CCD ensures that only the Earth is visible. This mask can be seen as pixelation on Earth's horizon. The mask also excludes stars from view, although they would not be bright enough to be visible to this camera.
Image Credit: NTs OMZ (http://eng.ntsomz.ru/electro).
Image processing by James Tyrwhitt-Drake"
Friday, November 14, 2014
Wednesday, November 12, 2014
Philae's descent via NASA
Image Credit: ESA/Rosetta/Philae/DLR
"This image of comet 67P/Churyumov–Gerasimenko was taken by the Philae lander of the European Space Agency's Rosetta mission during Philae's descent toward the comet on Nov. 12, 2014. Philae's ROLIS camera took the image from a distance of approximately two miles (three kilometers) from the surface.
After more than a decade traveling through space, a robotic lander built by the European Space Agency has made the first-ever soft landing of a spacecraft on a comet.
Mission controllers at ESA's mission operations center in Darmstadt, Germany, received a signal confirming that the Philae lander had touched down on comet 67P/Churyumov-Gerasimenko on Wednesday, Nov. 12, just after 8 a.m. PST/11 a.m. EST.
A statement about Rosetta from John Grunsfeld, astronaut and associate administrator for NASA's Science Mission Directorate, is online at: http://go.nasa.gov/1u2fQZE"
Left: earlier image of comet 67P/Churyumov–Gerasimenko prior to today's landing.
"Rosetta’s Plasma Consortium (RPC) has uncovered a mysterious ‘song’ that Comet 67P/Churyumov-Gerasimenko is singing into space. The comet seems to be emitting a ‘song’ in the form of oscillations in the magnetic field in the comet’s environment. It is being sung at 40-50 millihertz, far below human hearing, which typically picks up sound between 20 Hz and 20 kHz. To make the music audible to the human ear, the frequencies have been increased in this recording. Thumbnail image credit: ESA/Rosetta/NAVCAM – CC BY-SA IGO 3.0"
"This mosaic comprises four individual NAVCAM images taken from 31.8 km from the centre of Comet 67P/Churyumov-Gerasimenko on 4 November 2014. The image resolution is 2.7 m/pixel and thus each original 1024 x 1024 pixel frame measured 2.8 km across. The mosaic has been slightly rotated and cropped, and measures roughly 4.6 x 3.8 km.
Credit: ESA/Rosetta/NAVCAM, CC BY-SA 3.0 IGO"