March 08 – 65 Cybele

One of these days I’ll do a blog on orbital resonance (but it’ll make my head hurt, so not today).  Today I’ll just be mentioning that asteroid 65 Cybele was discovered on March 8th 1861, and now gives its’ name to a whole family of similar bodies in the outer asteroid belt, who orbit just past the “2:1 orbital resonance” with Jupiter.

Cybele was discovered by Ernst Wilhelm Leberecht Tempel (1821-1889), a comet hunter by inclination, but he managed to find five asteroids as well.  If the name sounds familiar, it might be because he discovered the comets 55P/Tempel-Tuttle (parent of the Leonids) and 9P/Tempel, target of the Deep Impact probe.

Measuring something as small and far away as an asteroid isn’t easy from Earth, but best guesses using IRAS observations, give an average diameter (if Cybele were round, which it isn’t) of approximately 240km (about 150 miles).  That’s kind of like a spherical Wales, so when I say small it’s all relative – it wouldn’t feel small if it decided to head this way.

Statue of Cybele from Lazio.
Statue of Cybele from Lazio.

Cybele was a goddess of Phrygia (now part of Turkey) adopted by the Greeks as they colonised the area and brought back home to join their large collection of deities.  She is a “mother goddess” with similar attributes to the already well-established deities Gaia, Rhea and Demeter; but this doesn’t seem to have worried the Greeks, who always seemed to be on the lookout for someone new to worship.

1888  –  Asteroid 273 Atropos discovered by Johann Palisa.  Atropos was the oldest of the fates in Greek mythology.  Her job was to decide the method of death of every mortal.

1893  –  Main belt asteroid 358 Apollonia was discovered by Auguste Charlois.

1894  –  Exactly one year later, Charlois discovered asteroid 389 Industria, an S-type body of about 79 km in diameter.

1967  –  OSO 3 launched from Cape Canaveral.  This was the third of the Orbiting Solar Observatories, and was bristling with experiments to measure x-rays, gamma rays, thermal radiation, and cosmic rays.  OSO 3 was the first orbiting observatory to detect an extrasolar X-ray source.  This was Scorpius X-1, a neutron star, and the strongest source of Earth-bound  x-rays aside from the Sun.