September 19 – Discovery of Asteroid 48 Doris (1857)

Asteroid 48 Doris is a large main belt asteroid, and one of two to be spotted on September 19th 1857 by Hermann Goldschmidt.

The Doris after whom the asteroid was named was an Oceanid (a daughter of Oceanus and Tethys).  She had one son and fifty daughters, collectively known as the Nereids after their father Nereus.  She was Achilles’ grandmother.

Doris and Hippocamp

Today’s accompanying visual aid shows a rather sour-looking Doris riding a hippocamp (literally “horse monster” in Greek).


 

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September 19 – Birth of Astronomer C H F Peters (1813)

Christian Heinrich Friedrich Peters  was born in Koldenbüttel (which was in Denmark at the time) on September 19th 1813, and became a big name in asteroid spotting, finding 48 in all, which makes him second in the all-time list of visual asteroid discoveries after Johann Palisa.

Peters was a bit of a radical in his youth, and while living in Italy his attempts to avoid the attentions of the authorities ended up with his fleeing to Turkey, where he made the acquaintance of the American ambassador, and before long found himself across the Atlantic mixing with the Harvard scientific community, and speaking in front of the American Association for the Advancement of Science in Rhode Island.

C H F Peters

Peters settled down at Hamilton College in Clinton, NY, as professor of astronomy, and as we have been hearing in this blog at irregular intervals all year, he made good use of their large 13½ inch refractor, working on sunspots by day and looking for asteroids at night.  I’m not sure when he slept.

His work was greatly aided by a supplement added to his rather meagre salary by a local businessman, who had the college observatory re-named after himself in return (to the Litchfield Observatory).  

Peters discovered his last asteroid, 287 Nephthys, at the age of 76, less than a year before his death.  He died on his way to the observatory, on July 19th 1890.


ALSO TODAY:

 

September 18 – 375 Ursula / 1965 S1 Ikeya-Seki

Comet C 1965 S1 Ikeya-Seki was first spotted on September 18th 1965 by Kaoru Ikeya and Tsutomu Seki, observing independently of one another. At magnitude -10 it was visible in daylight, and has earned the name The Great Comet of 1965.

Ikeya-Seki (photograph by Maynard Pittendreigh)
Ikeya-Seki (photograph by Maynard Pittendreigh)

Ikeya-Seki is one of a group of over-performers known as the Kreutz Sungrazers. The group also contains the Great Comets of 1843 and 1882, and is thought to comprise fragments of a huge parent comet that broke up in 1106.

The photograph above by Carolina astronomer (and Presbytarian minister) Maynard Pittendreigh might look a little dated to the Hubble generation, but to me it’s just fabulous.  It was probably all accidental, and he might have been going for a perfect shot, but I love the star trails, the scratches, the unidentified smear in the centre, and the telegraph wires.   It wouldn’t look out of place in a futuristic film from the early twentieth century, or a Bogus Blimp video.

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ALSO TODAY . . .

“Cool Jovian-mass” extrasolar planet MOA-2007-BLG-400Lb discovered today in 2008 in Sagittarius by Subo Dong and others.

Asteroid 375 Ursula is a fairly bulky main belt asteroid (approx 216 km diameter) discovered by Auguste Charlois on September 18th 1893. Ursula is another one of his finds with no readily apparent reasoning behind the name (you may recall 298 Baptistina from September 9th). If I could only find out on what date the naming happened, and maybe who came up with “Ursula” (it isn’t always the discoverer) I might get somewhere.

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September 17 – Discovery of Saturn’s Moon, Mimas (1789)

Mimas, or Saturn I, (sometimes known as the “Death Star” for reasons obvious to anyone who’s ever seen one of the original Star Wars films) was discovered on September 17th 1789 by William Herschel. It’s a heavily cratered, 396 km wide, low density moon with one really obvious surface feature: the 130 mile wide crater Herschel. It’s hard to imagine how Mimas managed to survive the impact of a body capable of forming such a gigantic hole, and there are fractures on the opposite side of the moon that may indicate it nearly didn’t.

Mimas from Cassini. (Image credit: NASA / JPL)
Mimas from Cassini. (Image credit: NASA / JPL)

Mimas has proved irresistible to a succession of spacecraft visiting Saturn and its environs. Pioneer 11, Voyager 1 and Voyager 2 all flew past, and Cassinihas taken some very close shots from less than 10,000 km away.

Mimas, like the other six satellites of Saturn known at the time, was named after one of the Gigantes (giants) of Greek mythology. The names were suggested by John Herschel, son of William.


ALSO TODAY . . . .

1976 – Space Shuttle Enterprise (OV-101), the first of her kind, was rolled out of her construction plant for a photo opportunity with Gene Roddenberry and the cast of Star Trek. The phrase “roll out” is particularly apt in this case, as Enterprise was intended for testing in Earth’s atmosphere only, and so was built without engines.

1930 – Birth of Thomas P Stafford, veteran of Gemini and Apollo missions (21 days in space), commander of the second manned mission to orbit the Moon.


September 16 – Discovery of Saturn’s Moon, Hyperion (1848)

Hyperion is an unusual moon of Saturn.  It was discovered on September 16th 1848 by three astronomers: William Lassell of Liverpool (on his own), and Americans William Cranch Bond and his son George Phillips Bond (together).  The Bonds spotted the moon first, but Lassell got published first, so all three are credited.  They are honored together in the form of the only named feature on Hyperion, a prominent ridge called the Bond-Lassell Dorsum.

Hyperion (image credit: NASA/JPL/Space Science Institute)
Hyperion (image credit: NASA/JPL/Space Science Institute)

It’s an odd place, Hyperion.  You can tell from the photograph that it isn’t a regular shape, suggesting it may be the remnant of a larger body destroyed by an impact at some point long ago, and appears to be a bit like a bath sponge (i.e. mostly holes) or the papery wasp’s nest I extracted from our bird box last autumn following a Summer spent creeping up to it with an insect spray and running away as fast as possible after giving them a quick blast in the entrance.  Latest calculations suggest that as much as 40% of the moon’s volume is empty space, and what solids there are may turn out on closer inspection to be mostly water ice, with a sprinkling of frozen methane and carbon dioxide, and only a small percentage of rock.  Hyperion is the second largest moon in the Solar System to have an irregular shape, and is the largest with a “chaotic” (wobbly) rotation.

Hyperion was first visited by Voyager 2 in August 1981, where its unusual shape and rotation were the subject of much head-scratching.  Voyager only got to within about 300,000 miles though, so it was left to the Cassini mission to reveal the full oddness of the moon’s surface when it got to a mere 628 miles (1010 km) in September 2005.  Cassini took today’s  first photograph.

In Greek mythology, Hyperion was a Titan.  There were twelve of them, and they were the children of the old gods Gaia and Uranus.  Hyperion married Theia, his sister (as usual) and had three children with her: Helios (the Sun), Selene (the Moon) and Eos (the Dawn).  So today’s second photograph (aren’t you lucky?) is the Horse of Selene from the east pediment of the Parthenon (now in the British Museum).  I first saw this sculpture when I was seventeen, on a sixth form trip to London.  If I’d paid more attention to my teacher, Mr Perry, at the time I could probably tell you all sorts of facts about it, but alas.

The Horse of Selene.
The Horse of Selene.

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ALSO TODAY  . . . . 

C-type main belt asteroid 105 Artemis was discovered on September 16th 1868 by J C Watson, and named after the Greek goddess of the hunt.

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September 15 – Discovery of Asteroid 47 Aglaja (1857)

47 Aglaja (the “aja” is pronounced like the “iar” in “friar”) is a C-type main belt asteroid, about 140 km (80 miles) wide, following a fairly average path around the Sun at a fairly average speed of about 17.5 km/s.  It was discovered on September 15th 1857 by one of our regular contributors, Robert Luther, and  was named after one of the Charites of Greek mythology (who have become more famous under their Roman name of the Graces).  Aglaia (or Aglaea) was responsible for splendour.  We have already encountered another of the trio, Euphrosyne, (“mirth”) on September 1st, but we won’t be coming across the third, Thalia (“good cheer”), because she shares her name with the more popular Muse of Comedy, who we will probably meet on December 15th.

The Three Graces
The Three Graces

Today’s accompanying artwork is by the German artist  and former student of Albrecht Dürer, Hans Baldung (c. 1484 to 1545).  In this painting I have no idea which Grace is which.  There is probably a clue in the book being read by the grace on the left, and the lute-like instrument carried by the one on the right, but their identification eludes me.


September 14 – Discovery of Asteroid 60 Echo (1860)

60 Echo is an S-type asteroid, discovered September 14th 1860, fairly large at about 60 km in diameter, with a day lasting 25 hours and a year equivalent to 3.7 of our own.  It was the third and final asteroid to be found by American astronomer James Ferguson, working out of the US Naval Observatory. He named it Echo when his first choice, Titania, turned out to have already been taken.

Echo and Narcissus
Echo and Narcissus

Echo, a mountain nymph, was punished in a peculiar and inventive way by Hera, who was annoyed at being distracted by Echo’s stories while her husband Zeus was off ravishing other nymphs. The punishment was to make Echo unable to speak except to repeat the words of others. Today’s painting of Echo and Narcissus, is in my local art gallery: the Walker (Liverpool). It is by John W Waterhouse.


ALSO TODAY:

Asteroid 62 Erato is our second Themistian asteroid in a week.  This one, a C-type of about 65 km wide, was the first asteroid to have two credited discoverers.  They were Otto Lesser and Wilhelm Foerster, and the discovery was made on September 14th 1860.  Erato was named after the Greek muse of lyric and love poetry, often portrayed holding a lyre or kithara ( a lyre for professionals).


September 13 – Discovery of Asteroid 104 Klymene (1868)

Asteroid 104 Klymene is a Themistian asteroid, discovered by J C Watson on September 13th 1868. The Themistians are a family of C-type asteroids, named after 24 Themis (and including 62 Erato, coming up tomorrow).

Klymene and Hera

The name Klymene (or Clymene) crops up quite a few times in Greek mythology, but one of them, an attendant to Hera, stands out in my mind as being the most likely candidate for today’s rock, when you consider that the asteroid named immediately before this one was 103 Hera. This particular Klymene was an Oceanid (daughter of Oceanus) and you can see her, with Hera, in today’s picture, a detail of a depiction of the Judgement of Paris from the Badisches Landesmuseum, Karlsruhle.


September 13 – Birth of Horace W Babcock (1912)

Horace Welcome Babcock (fantastic name), astronomer and inventor, was born today in 1912, son of solar specialist Harold D Babcock.  Babcock junior was the chap who realised that changing the shape of mirrors can be used to reduce the distorting effect of turbulence in the Earth’s atmosphere on light from distant objects (called adaptive optics). Unfortunately he made this discovery in the 1950s, roughly 40 years before the technology to actually do it became available.

(Image credit: tricky. I think it’s Babcock’s own photo.)

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September 12 – Gemini XI

Gemini XI, launched on September 12th 1966, was the 17th manned US spaceflight, and the 9th manned flight of the Gemini programme. It was crewed by Charles “Pete” Conrad and Richard “Dick” Gordon. The main aim of the mission was to rendezvous with an Agena Target Vehicle, to simulate the return of a Lunar Module to the Command/Service Module following a landing. Several such rendezvous were performed successfully, as well as two periods of extra-vehicular activity (that’s space walks to you and me).

The Crew of Gemini XI
The Crew of Gemini XI (image credit: NASA)

Pete Conrad would go on to spend over 1,000 hours in space on four missions, and become the third human to walk on the Moon (Apollo XII). He died in 1969 after being thrown from his Harley-Davidson. Dick Gordon only had two spaceflights under his belt. As well as achieving a record altitude of 850 miles with Conrad, he joined him in Apollo XII as pilot of the command module.



ALSO TODAY . . .

Asteroid 59 Elpis is a rather large, dark (albedo 0.04) C-type asteroid in the main belt. It has a diameter of 165 km. Elpis was discovered by Jean Chacornac on September 12th 1860 (it was his last find). The name Elpis was chosen by Karl L Lithow, director of the Vienna Observatory. Elpis is the personification of ‘hope’ in Greek mythology, and was supposedly the only item left in Pandora’s pithos (jar, not box) after she had emptied it.


Firstly, asteroid 117 Lomia was discovered by Alphonse Borrelly on September 12th 1871 from Marseilles. It has a nearly circular orbit, and in composition is somewhere between a C-type and an X-type. The origin of the name is unknown.


And secondly, asteroid 241 Germania (C-type, main belt) was discovered today in 1884 by Robert Luther in Düsseldorf. He named it, obviously, after his homeland. I was tempted here to insert a photograph of a moustachioed general in a uniform and spiky helmet, but I resisted. No racial stereotypes here.