December 22 – Discovery of Asteroid 323 Brucia (1891)

Thirty-three kilometre wide asteroid 323 Brucia was the first to be discovered by the new fangled process known as astrophotography.

It was discovered by Max Wolf, and named in honour of Mrs Catherine Wolfe Bruce, who had donated the instrument on which it was captured, the 16 inch double astrograph at Heidelberg.

The Bruce Astrograph, Heidelberg

Mrs Bruce was a generous supporter of astronomy (she also provided instruments for Harvard and Yerkes), and now, as well as an asteroid, has a lunar crater named after her. She established an annual award for the Astronomical Society of the Pacific, the “Catherine Wolfe Bruce Gold Medal”, one of the most prestigious awards in astronomy. Over the years the Bruce Medal has been awarded to the likes of Poincaré, Hubble, Hoyle and Chandrasekhar, and also to a certain Max Wolf, who received the honour in 1930.

I’ve included a picture of the Bruce Medal because photographs of Catherine are hard to come by.  There’s one doing the rounds online, but I’m fairly sure it isn’t her, so I’m not using it.

September 29 – Discovery of Asteroid 243 Ida (1884)

243 Ida was discovered by by the Austrian astronomer Johann Palisa on September 29th, 1884, and unlike most bodies in the main asteroid belt, this particular S-type asteroid has been studied at close quarters. Ida was visited by the Galileo spacecraft in 1993. It is one of the larger members of the Koronian family of asteroids, about 6000 strong, who orbit as a group, and are thought to be the remains of a collision involving a single, larger body. Thanks to Galileo, we have pretty good photographs of Ida, and we now know it has a small companion, Dactyl.

Ida and Dactyl, courtesy of Galileo (image: NASA/JPL)

Dactyl is pretty teeny, measuring just over a kilometre across in most directions. It is the small dot on the right side of Ida in the photograph, and was the first moon discovered orbiting an asteroid. The name comes from a race of mythical beings who inhabited Mount Ida in Crete. They are credited with discovering how to use fire to work metal.

The asteroid itself is named for the nymph who, with her sister Adrasteia, was entrusted with caring for the infant god Zeus. The name was the idea of Moriz von Kuffner, an Austrian brewer, philanthropist and astronomer, who founded the Kuffner Observatory in Vienna. Kuffner eventually got his own named asteroid, but not until 2006 (number 12568).

Also as a result of the Galileo visit, I will be abandoning my usual use of the words “about” and “approximately”, and will be stating that Ida’s principal dimensions are 59.8 km by 25.4 km by 18.6 km, with a mean radius of 15.7 km (Belton et al, 1996).

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 10 – Discovery of Asteroid 55 Pandora (1858)

Asteroid 55 Pandora was discovered today in 1858 by American astronomer and priest George Mary Searle.  Pandora is a large, bright E-type asteroid.  The E-types are a group of enstatite- bearing asteroids, usually quite small, (Pandora is one of the exceptions) all thought to originate from a much larger body, now broken up.  Searle only discovered one asteroid, but with six galaxies under his belt I suppose he was happy enough.

Pandora (East façade of the Cour Carrée in the Louvre palace, Paris.) Image: © Marie-Lan Nguyen / Wikimedia Commons
Pandora (East façade of the Cour Carrée in the Louvre palace, Paris.) Image: © Marie-Lan Nguyen / Wikimedia Commons

Pandora (above) was supposedly, according to Greek mythology, the first human woman, created on the orders of Zeus.  We all think we know about Pandora, of course, and we are all wrong.  A poor translation of the Greek word pithos (“jar”) into pixos (“box”) has fooled us all.


. . . asteroid 231 Vindobona was discovered in 1882.  It’s a dark main-belter, discovered by our most regular contributor to the list, Johann Palissa, and given the Gaulish name for Vienna (literally “white bottom”).


September 09 – Discovery of Asteroid 61 Danaë (1860)

Asteroid 61 Danaë  –  discovered September 9th 1860. Danaë is a large, rocky S-type asteroid of about 80 km diameter in the main belt, rotating every eleven and a half hours. It was discovered from Paris by Hermann Goldschmidt, but named by fellow asteroid hunter Robert Luther after the mother of Perseus.  The father was, as usual, Zeus, who impregnated her in the guise of a shower of golden rain (no comment).

Danaë, in playful mood.


Asteroid 56 Melete discovered, 1857.

Asteroid 189 Phthia discovered, 1878.

Asteroid 297 Caecilia  discovered, 1890.

Asteroid 298 Baptistina discovered, 1890.

June 28 – Discovery of Asteroid 259 Aletheia (1886)

Another one from the golden age of minor planet discovery, the 1880s.  259 Aletheia was discovered on June 28th 1886 by C F H Peters, one of the most successful asteroid hunters of the nineteenth century.  He will be our birthday boy on September 19th.

Aletheia is a large main belt asteroid of about 178km diameter, rotating every 15 hours (quite fast), with an absolute magnitude of 7.76 (reasonably dim), and an albedo of 0.043 (very dark).

Veritas / Aletheia
Veritas / Aletheia

Today’s black rock is named after the Greek goddess of truth and sincerity (her Roman equivalent is Veritas).  The Greeks had a god or goddess for just about everything, but this is particularly so when it comes to emotions.  This makes for a vast supply of potential astronomical names, not all of which have been used yet, for example Eris (strife – used), Ate (ruin – used), Dolus (cunning – not used) and Metus (fear – not used).

May 12 – Asteroids 633 Zelima and 634 Ute

Asteroids 633 Zelima and 634 Ute were both discovered on May 12th, 1907 by German astronomer August Kopff (1882-1960) from the Heidelberg Observatory.

August Kopff

Ute was named after an acquaintance of the discoverer, because she had recently become engaged, but I have a problem with the prevailing theory regarding the naming of Zelima.  It’s officially “unknown”, which is fine, but the theory suggests it was plucked from thin air because the letters “Z” and “M” were in the provisional designation (the name before it had a name) of asteroid “1907 ZM”.

Now I never met the guy, but Kopff doesn’t strike me as being short of a name or two for his discoveries.  I”ve trawled through a load of them, and none of the rest seem to use this method.  Zelima is a German girl’s name, and according to it was at its most popular between 1900 and 1909.  So I suspect a better theory might be that today’s asteroid was named after the new daughter of one of Kopff’s friends or colleagues.

Created May 2019.