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Dr Chris ArridgeDr Chris Arridge studies the giant planets of our solar system, working particularly on Saturn using NASA’s Cassini spacecraft and developing new mission ideas for a spacecraft to go to Uranus. His favourite planets are Mars and Neptune. When he’s not studying the planets he reads, runs, and dances Rockabilly Jive and Lindy Hop.

He’s originally from Hull and studied Physics with Planetary and Space Physics at the University of Wales, Aberystwyth, Applied Mathematics and Theoretical Physics at the University of Cambridge, and got his PhD in Space Physics from Imperial College London. He is a Royal Society University Research Fellow and Lecturer at University College London’s Mullard Space Science Laboratory.

David ArdittiDr David Arditti has been an amateur astronomer since age 11, having been inspired by a book by Patrick Moore he found in the school library. He later gained a BSc in Physics and a PhD in Materials from Imperial College, London. He now writes and lectures on astronomy, particularly on the serious contributions that amateur observation can make to our knowledge. He is a Council Member of the British Astronomical Association and Publicity Officer for the West of London Astronomical Society, and has been on the committee organising National Astronomy Week 2014. He has been observing Jupiter for over 30 years, and these days puts most effort into obtaining high-resolution images of the planet with the 14-inch telescope in his observatory in Edgware, North London. He is a frequent contributor to Astronomy Now magazine and the Journal of the BAA. He is also a classical composer, and is often seen around London on his bike.

RMRobert Massey chairs the Steering Group for NAW 2014. In his day job he works for the Royal Astronomical Society, helping to make the case for supporting research in astronomy. Formerly a teacher and Public Astronomer in Greenwich, he always enjoys talking astronomy with people of all backgrounds. When lucky enough to have the combination of good weather and a decent telescope, Jupiter is one of his favourite objects in the night sky.



    M, age 10, from Eastbourne, asked:  “How big is Jupiter?”

Dr Arridge replies: ”

“Jupiter is 143,000 km across its middle – that’s over 11 times wider than Earth and the Sun is a bit less than 10 times wider than Jupiter.  Jupiter isn’t shaped like a ball like Earth, it’s a bit squashed top to bottom, so it’s only 134,000 km from top to bottom.”

C, age 13, from St. Helens, asked: “How frequent are Jupiter’s Great Red Spot storms?”

Dr Arridge replies: ”

“The Great Red Spot is a vortex (like you see in a sink while water is going down the plughole) and has possibly been going for over 300 years.  It was first spotted in 1664/1665 and we have some evidence that it may have disappeared for a while but was re-observed in 1830 and has been continuously studied since 1878, making it over 180 years old at least. The Great Red Spot is just one of a many vortices (the plural of vortex) seen in Jupiter’s atmosphere. These vortices last for a few years up to hundreds of years.”

E, from Manchester, asked:  “When and how was Jupiter discovered and who named it?”

Dr Arditti replies: ”

“We do not know who discovered Jupiter, as it has been known about since the earliest astronomical writings that we have, which date from the Babylonian civilisation (located in present-day Iraq) around 4000 years ago. The name that we use comes from the Romans around 2000 years ago, but that came from earlier Indo-European origins, and means “Father Sky-God” or “Father Day-God”. To many ancient civilisations, Jupiter represented the king of the gods, as it moved in a stately manner from one constellation of the zodiac to the next annually.”

M, age 9, from East Sussex, asked: “What makes the Red Spot so red?”

Dr Arridge replies:

“The Great Red Spot sticks out a bit like a mushroom about 8 km above the highest clouds on Jupiter and we don’t really know for sure what gives it its colour. Some scientists think that it’s produced by organic chemicals in the atmosphere, phosphorus or sulphur and they’ve done laboratory experiments to get evidence that this might be true. But until we fly a probe through the Great Red Spot, or make better observations with telescopes we won’t have any better evidence.”