America’s newest next-generation Earth observing weather satellite, NOAA’s GOES-16, has returned its first high-definition images of Earth—one of which even includes the Moon!
It may not be the first (or even second or third) satellite mission that comes to mind but NASA and JHUAPL’s TIMED mission continues to deliver invaluable data about Earth’s upper atmosphere over 15 years after its launch on Dec. 7, 2001. In fact its extended long-duration stay in orbit has allowed TIMED (Thermosphere Ionosphere Mesosphere Energetics and Dynamics) to completely change what we thought we knew about how the uppermost layers of our atmosphere react to incoming storms from the Sun…and how it’s being affected by increasing amounts of carbon dioxide from below.
Read more at TIMED Marches On — 15 Years and Counting
This week NASA’s Jet Propulsion Laboratory announced news of an object traveling around the Sun in an orbit that keeps it relatively close to our own planet. The object, a near-Earth asteroid (NEO) less than 300 feet (100 m) across, is designated 2016 HO3 and has in some reports been called a “new” or “mini” moon of Earth…but that’s not entirely true. More accurately 2016 HO3 is what’s known as a quasi-satellite, and is in a temporary (albeit long-lived by human standards) orbit that takes it on a “leapfrog” path around Earth, never getting closer than 38 times the distance to the Moon—about 9.1 million miles.
Captured by the EU’s Copernicus Sentinel-3A satellite on Feb. 29, 2016, this beautiful composition of blacks, purples, and blues shows the twilight transition across the Norwegian archipelago of Svalbard, located north of the Arctic Circle between Norway and the North Pole. The snow-covered and fjord-cut large island of Spitsbergen can be seen at the right edge, while sea ice and clouds follow their own swirling currents on and above the Greenland sea.
This is the first image acquired by the spacecraft, which was launched aboard a converted-ICBM Rockot vehicle on Feb. 16 from Russia’s Plesetsk Cosmodrome. The first of two planned Sentinel-3 satellites, 3A is currently in a high-inclination orbit at an altitude of 505 miles (814 km).
Drumroll please… the little moon Telesto! (You like it, you really like it!) This image, captured by Cassini on Jan. 14, 2016, shows Saturn’s moon Telesto – a “leading trojan” of the much larger satellite Tethys.
A trojan moon is one that orbits a parent body within the same path as a more massive satellite, positioned at the Lagrangian points L4 and L5… usually at 60º ahead and behind within the orbit relative to the overall center (which, in the case of Tethys, is Saturn.)
The irregularly-shaped, 15-mile (24-km) -wide Telesto rides around Saturn ahead of Tethys, making it the moon’s “leading” trojan. Its slightly larger sister Calypso follows behind Tethys as the trailing trojan. All three orbit the ringed planet at a distance of over 183,000 miles (294,000 km).
On the afternoon of Friday, May 31, 2013, at 4:59 p.m. EDT, the nearly two-mile-wide asteroid 1998 QE2 will pass by our planet at a distance of about 5.86 million km (3.64 million miles)… about 15 times the distance between Earth and the Moon. And although it poses no threat of impacting Earth neither during this pass nor in the foreseeable future, on the eve of its close approach NASA revealed a surprising discovery about this cosmic visitor: it has a little moon of its very own!