Comet of the Week: ATLAS C/2019 Y4
Perihelion: 2020 May 31.04, q= 0.251 AU Last year, when I selected the various comets I would be using for “Ice and Stone 2020”’s “Comets of the Week,” I did so with the knowledge – and even hope – that I might find it necessary to swap one or more such selections for current comets …
Special Topic: Occultations by Asteroids
In astronomy, an occultation – which comes from Latin words meaning “to hide” – occurs when one body passes in front of, and thus for a time hides, another body. (In this context, a solar eclipse can be considered as a kind of occultation.) In its most common usage, an occultation usually refers to the …
QuizMe: Hubble Space Telescope
The Hubble Space Telescope marked the 30th anniversary of its deployment, far exceeding its initial expected lifespan of only a single decade. While the scientific operation of the space-based telescope got off to a rocky start, a series of repair missions and upgrade by NASA astronauts have made certain that Hubble has become our vista …
This Week in History: April 26-May 2
APRIL 26, 1803: A collection of over 3000 meteorites falls and lands near the town of L’Aigle in Normandy, France. Up until then the existence of “stones falling from the sky” had been harshly debated, but the L’Aigle meteorite fall conclusively proved that such events happen, and in effect gave birth to the study of …
Comet of the Week: Bradfield C/2004 F4
Perihelion: 2004 April 17.09, q= 0.168 AU One of the most legendary comet discoverers of the 20th Century was the Australian amateur astronomer William Bradfield, who resided near Adelaide, South Australia. By trade a rocket propulsion engineer with the Australian government until his retirement in 1986, Bradfield began a systematic visual comet hunting effort at …
Special Topic: Meteorites
Interplanetary space in the vicinity of Earth’s orbit – and, presumably, elsewhere as well – is littered with debris. Dust ejected from comets, bits and pieces of asteroids, rocks from various bodies . . . Meanwhile, Earth during its annual orbits around the sun is constantly sweeping up this debris. From the standpoint of terminology, …