HistoryIce and StoneWeek 36

AUGUST 30, 1979: The SOLWIND coronagraph aboard the U.S. Defense Department’s P78-1 satellite records images of a bright comet approaching the sun, and then disintegrating. This comet, the first comet ever to be discovered from space, turned out to be a Kreutz sungrazer, and was the first of several comets discovered by SOLWIND prior to …

CometIce and StoneWeek 36

Perihelion: 1979 August 30.95, q = 0.005 AU  The very first comet I ever observed, Comet Tago-Sato-Kosaka 1969g – a previous “Comet of the Week” – was also the first comet ever to be observed from space, an event which took place in mid-January 1970. Since that time many, many comets have been observed by …

Ice and StoneTopicWeek 36

Where the various comets that we see in our skies come from has long been a subject of high scientific interest. The Week 3 “Special Topics” presentation discussed how in the mid-20th Century the Dutch astronomer Jan Oort proposed the existence of the structure that we now call the “Oort Cloud” as being the source …

Moon

The Blue Origin National Team of four US aerospace companies has delivered a full-scale engineering mockup of their proposed human lunar lander to NASA’s Johnson Space Center as part of NASA’s ambitious Artemis Moon program to return astronauts to the lunar surface by 2024. The Artemis Human Landing System (HLS) lander has been set up …

AstronomyEarth

The Histories by Herodotus (484BC to 425BC) offers a remarkable window into the world as it was known to the ancient Greeks in the mid-fifth century BC. Almost as interesting as what they knew, however, is what they did not know. This sets the baseline for the remarkable advances in their understanding over the next …

HistoryIce and StoneWeek 35

AUGUST 23, 1862: The comet now known as Comet 109P/Swift-Tuttle passes through perihelion at a heliocentric distance of 0.963 AU. The comet had been discovered the previous month independently by Lewis Swift and Horace Tuttle, and became a conspicuous naked-eye object. It is the parent comet of the Perseid meteor shower and is a future …

CometIce and StoneWeek 35

Perihelion: 1769 October 8.12, q = 0.123 AU  As discussed in the “Special Topics” presentation on that object, in the early 18th Century the British astronomer Edmond Halley predicted that the comet that now bears his name would be returning around 1758. As that time approached several astronomers became involved in the effort to search …

Ice and StoneTopicWeek 35

The “Special Topics” presentation two weeks ago pointed out that the term “small bodies” of the solar system generally refers to objects like comets and asteroids, although that particular presentation discussed another class of such objects, i.e., the small moons of the planets. To carry the term “small bodies” to an extreme, we could examine …

ISS

NASA is targeting no earlier than Oct. 23 for the first operational flight of the commercial SpaceX Crew Dragon spacecraft with astronauts launched by a Falcon 9 rocket to the International Space Station as part of the agency’s Commercial Crew Program – following the recent conclusion of the historic Demo-2 test flight to the station …

HistoryIce and StoneWeek 34

AUGUST 16, 1898: DeLisle Stewart at Harvard College Observatory’s Boyden Station in Arequipa, Peru, takes photographs on which Saturn’s outer moon Phoebe is discovered, although the images of Phoebe were not noticed until the following March by William Pickering. Phoebe was the first planetary moon to be discovered via photography, and it and other small …