HIMALIA, THE JOVIAN MOON IS DISCOVERED IN 1904

Today, The Grandma has been reading about Himalia, the satellite of Jupiter that was discovered by Charles Dillon Perrine on a day like today in 1904.

Himalia, also known as Jupiter VI, is the largest irregular satellite of Jupiter. With a diameter of at least 140 km, it is the sixth largest Jovian satellite, after the four Galilean moons and Amalthea.

It was discovered by Charles Dillon Perrine at the Lick Observatory on 3 December 1904 and is named after the nymph Himalia, who bore three sons of Zeus, the Greek equivalent of Jupiter. It is one of the largest planetary moons in the Solar System not imaged in detail, and the third largest not imaged in detail within the orbit of Neptune.

Himalia was discovered by Charles Dillon Perrine at the Lick Observatory on 3 December 1904 in photographs taken with the 36-inch Crossley reflecting telescope which he had recently rebuilt.

Himalia is Jupiter's most easily observed small satellite; though Amalthea is brighter, its proximity to the planet's brilliant disk makes it a far more difficult object to view.

Himalia is named after the nymph Himalia, who bore three sons of Zeus, the Greek equivalent of Jupiter. The moon did not receive its present name until 1975; before then, it was simply known as Jupiter VI or Jupiter Satellite VI, although calls for a full name appeared shortly after its and Elara's discovery.

The moon was sometimes called Hestia, after the Greek goddess, from 1955 to 1975.

At a distance of about 11,400,000 km from Jupiter, Himalia takes about 250 Earth days to complete one orbit around Jupiter.  

It is the largest member of the Himalia group, which are a group of small moons orbiting Jupiter at a distance from 11,400,000 km  to 13,000,000 km, with inclined orbits at an angle of 27.5 degrees to Jupiter's equator. Their orbits are continuously changing due to solar and planetary perturbations.

In November 2000, the Cassini spacecraft, en route to Saturn, made a number of images of Himalia, including photos from a distance of 4.4 million km. Himalia covers only a few pixels, but seems to be an elongated object with axes 150±20 and 120±20 km, close to the Earth-based estimations.

In February and March 2007, the New Horizons spacecraft en route to Pluto made a series of images of Himalia, culminating in photos from a distance of 8 million km. Again, Himalia appears only a few pixels across.

More information: NASA

When we first sent missions to Jupiter,
no one expected to find moons
that would have active volcanoes.
And I could go down a long list of
how often I've been surprised
by the richness of nature.

Alan Stern