• Photo by Nicolas J Leclercq on Unsplash
  • Photo by Nicolas Tissot on Unsplash
  • Photo by NASA on Unsplash
  • Photo by USGS on Unsplash

IAGA-IAPS Memorandum


IAGA and the International Association of Physics Students (IAPS) are taking joint efforts for academic growth by signing a Memorandum of Understanding. This has been done with the aim to establish future collaborations and to expand both the communities.

IAPS is an international, student-run educational association, which aims to encourage physics students in their academic and professional growth by developing an ever-growing worldwide community within which peaceful relations are established in a collaborative, diverse and friendly social environment.

The Naming Game : Moon Edition

What are moons? Moons are satellites that orbit around a planet. So, technically they'd be 'natural satellites of the planets' because "Moon" is just one, but, practically, don't we all just call them "moons"?! Currently, there are over 200 moons in our Solar System, and that's excluding the ones orbiting the dwarf or minor planets. 

Some moons have atmospheres, some have volcanic activities going on them and some even have oceans. Some moons orbit in direction of the rotation of planet and some orbit in opposite direction. But do you know how or what they are named?

The official names of celestial bodies are taken care of by the International Astronomical Union. Most of them are named after Greek and Roman mythology characters, but some are also named after literary characters.

While Mercury and Venus don't have any moons, our moon has many different names in different languages. The word "Moon" was named after two Latin words meaning 'to measure' and 'month'.

Mars, named after the Greek mythological God of war, Ares, has two moons -  Phobos and Deimos - named after the sons of Ares meaning 'fear' and 'dread'.

Jupiter has a plethora - 53 named moons and 26 unnamed ones. The planet is named after the Greek God, Zeus, and its moons are named after his lovers or descendants. Galileo first discovered the moons of Jupiter and hence the four biggest moons - Ganymede, Callisto, Io and Europa - are called the Galilean moons.

Saturn has such a large family of moons - around 82 which we know of - that there was a shortage for names. They were named after the Titans (children of Greek Gods Uranus and Gaia) and their descendants, but are now named also after the giants of the Norse, Gallic and Inuit mythology.

Uranus has 27 moons and they are named after Shakespeare's characters. A few are named after Alexander Pope's characters. Look them up to know if your favorite character made the cut; the maximum number coming from 'The Tempest'.

And finally, Neptune has 14 moons. Neptune, named after the Roman God of sea has its moons named after other Roman and Greek sea gods and nymphs.

Moons that are yet to be confirmed are named with a letter and year. 

Images : (1) Kevin Gill on Flickr. (2) Hubble. (3) Adobe Stock.

Shivangi Sharan is a second year PhD student at the Laboratory of Planetology and Geodynamics in France. Her research focusses on the study of the magnetic field of Mars and to infer its internal structure from it. She is an active member of the IAGA Blog Team and can be contacted via e-mail here.



A thorough insight into the International Geophysical Year (IGY) project from a 60‐year later perspective has been depicted by Y. Lyubovtseva, A. Gvishiani, A. Soloviev et al. in “Sixtieth anniversary of the International Geophysical Year (1957–2017) – contribution of the Soviet Union” published in the History of Geo‐ and Space Sciences journal (https://doi.org/10.5194/hgss‐11‐ 157‐2020). 

The IGY was the most significant international scientific event in geophysical sciences in the history of mankind. This was the largest international experiment that brought together about 300 000 scientists from 67 countries. Well‐planned activity of national and international committees was organized for the first time.

Read also about the "The IGY and Me" blogs published in our last blog here.

Contributed by the Chair of the Interdivisional Commission on History, Dr. Anatoly Soloviev, from the Geophysical Center, Russian Academy of Sciences, Moscow. The Commission encourages historical geophysical research and preservation of IAGA's history.