April 29, 2017, by Brigitte Nerlich

Cassini: Space probes, history and women

I have just read a lovely article by Rebekah Higgitt on the various Cassinis that worked in France as astronomers. One of them was Giovanni Domenico (or Jean Dominique) Cassini (8 June 1625 – 14 September 1712), the first director of the observatory founded by Louis XIV, and discoverer, amongst other things, of four satellites of the planet Saturn. He gave his name to the Cassini space probe (together with Huygens, of whom more below) which is currently making headlines, as it is flying between Saturn and its rings.

I absolutely loved the composite image that heads up the article, showing a photograph of Saturn’s rings taken from the Cassini Spacecraft in 2017 and a diagram of Saturn’s rings by Jean Dominique Cassini and published in 1676  in Philosophical Transactions (the journal published by the Royal Society here in the UK). These long arcs in the history of science and technology bring science and technology to life and give them depth – and made me think.

Space probes and their names: Diving into space and into history

Quite a few space probes can be used to establish these arcs of history and some enthusiasts might follow and admire them, while for others such names might be as arbitrary as any word in a language. I am a bit of an enthusiast, so I try to follow the arcs.

Looking at various lists of space craft, space probes, space telescopes, space observatories and so online, I realised that such naming of space crafts after astronomers like Cassini only started relatively recently (but somebody might have to do a bit more research on that).

Initially space probes had names like Sputnik (‘fellow traveller of earth’), Explorer, Beacon, Mariner, Pioneer, Vanguard, Viking, Voyager. Some mythological names also crept in, such as Luna, Ariel, Phobos, Ulysses, Juno, even ‘Ikaros’, and of course Rosetta and Philae!

Then gradually, names of famous astronomers began to be used for space crafts, such as:

Galileo: This is an American unmanned spacecraft that studied the planet Jupiter and its moons – named after Galileo Galilei (15 February 1564 – 8 January 1642), an Italian polymath: astronomer, physicist, engineer, philosopher, and mathematician.

Kepler: Kepler is a space observatory launched in 2009 by NASA to discover Earth-size planets orbiting other stars. It was named after Johannes Kepler (December 27, 1571 – November 15, 1630) was a German mathematician, astronomer, and astrologer.

Huygens: Huygens was an atmospheric entry probe that landed successfully on Saturn’s moon Titan in 2005 (in collaboration with Cassini, so to speak). It was named after Christiaan Huygens, FRS (14 April 1629 – 8 July 1695), a prominent Dutch mathematician and scientist. He is known particularly as an astronomer, physicist, probabilist and horologist.

Herschel: The Herschel Space Observatory was a space observatory built and operated by the European Space Agency and was active from 2009 to 2013. It was named after Frederick William Herschel, FRS (15 November 1738 – 25 August 1822), a British astronomer and composer of German origin, and brother of fellow astronomer Caroline Herschel, with whom he worked.

These crafts, probes and observatories allow us here down on earth not only to visit space, but, if we are so minded, also to voyage across time to explore long stretches of the history of science. They also show us images of ‘ourselves’ that shrink time and space and should make us feel rather humble and at one with each other.

NASA’s Cassini spacecraft captured this view of planet Earth as a point of light between the icy rings of Saturn on April 12, 2017. Credits: NASA/JPL-Caltech/Space Science Institute

Alongside these space probes named after ‘older’ historical figures, there are, of course, also those named after ‘younger’ ones:

Hubble: This a space telescope that was launched into low Earth orbit in 1990 and remains in operation – and its images adorn calendars and posters all over the world. It was named after Edwin Powell Hubble (November 20, 1889 – September 28, 1953), an American astronomer. He played a crucial role in establishing the fields of extragalactic astronomy and observational cosmology and is regarded as one of the most important astronomers of all time.

Planck: This is a space observatory operated by the European Space Agency from 2009 to 2013, which mapped the the cosmic microwave background at microwave and infra-red frequencies, with high sensitivity and small angular resolution. It was named after Max Karl Ernst Ludwig Planck, FRS (23 April 1858 – 4 October 1947, a German theoretical physicist whose discovery of energy quanta won him the Nobel Prize in Physics in 1918.

James Webb: The James Webb Space Telescope, previously known as Next Generation Space Telescope, is a part of NASA’s ongoing Flagship program. It is under construction and scheduled to launch in October 2018. It is the successor to the Hubble telescope. It was named after James Edwin Webb (October 7, 1906 – March 27, 1992), an American government official who served as the second administrator of NASA from February 14, 1961 to October 7, 1968.

These are all contraptions, indeed marvels of science and technology, through which we can observe space but also immerse ourselves in shorter stretches of the history of science, if we care to take the time. We might learn something….

Rebekah Higgitt has provided us with a great overview of ‘Cassini’ – from the man to the mission (take the time to read the article and the comments!). We now need a few more such articles about Huygens, Kepler, and so on.

Where are the women?

Most of all though, we need something else: We don’t just need mythical women as names for space craft, we need real women! Here are a few.

Why don’t we start with naming the next space probe Somerville or Mitchell or…. pick your favourite.

I’ll end with a quote I just found in a post on the astronomer Maria Mitchell: “Nothing comes out more clearly in astronomical observations than the immense activity of the universe. ‘All change, no loss, ’tis revolution all.’” As the blogger, Maria Popova, points out, “Maria Mitchell (August 1, 1818–June 28, 1889) played an enormous and lasting role in paving the way for women in science. [She was] the first recognized female astronomer in America and the first woman elected, unanimously, to the American Academy of Arts and Sciences”.


Posted in history of scienceScience Communicationspace