©Jarrad Pond/South Florida University.
The solar system is crowded with small objects like asteroids and comets. Most have stable orbits which keep them out of harm's way, but a small proportion of them are in orbits that risk them colliding with planets.
The smaller the objects, the more numerous they are, and the more frequent these collisions should occur. Collisions like the recent meteor seen over Chelyabinsk, Russia, in February 2013, are rare because the object was relatively large, around 17 meters across.
The giant planet Jupiter -- a big target with tremendous gravitational attraction -- gets hit far more often than the Earth, and these collisions are much faster, happen at a minimum speed of 60 kilometers per second.
Amateur astronomers observing Jupiter with video cameras have been able to observe three of these collisions in the last 3 years and a detailed report of these collisions has been presented at the European Planetary Science Congress at UCL this week by Ricardo Hueso (University of the Basque Country, Spain).
"Our analysis shows that Jupiter could be impacted by objects around 10 meters across between 12 and 60 times per year," Hueso says. "That is around 100 times more often than the Earth."
The study, a broad collaboration between professional and amateur astronomers, also includes detailed simulations of objects entering Jupiter's atmosphere and disintegrating at temperatures above 10,000 °C and observations from telescopes such as the Hubble Space Telescope or the Very Large Telescope of the impact area taken only tens of hours after the impact. Despite observing the planet soon after the impact, Hubble and the VLT saw no signature of the disintegrated objects, showing that such impacts are very brief events.
Because the glow of these impacts is so short-lived, and they happen at unpredictable times, major observatories like Hubble and the VLT cannot reliably observe them -- these telescopes have packed observing schedules and cannot be dedicated to long-term monitoring of a planet. Amateur astronomers, who can dedicate night after night to observing a planet, have a far better chance of spotting these impacts, even if their equipment is far more rudimentary.
EPSC 2013 Press Officer
Universidad del Pa's Vasco
The first of these collisions was observed by A. Wesley from Australia and C. Go from Philippines on June, 3 2010. The second object was observed by three Japanese amateur observers (M. Tachikawa, K. Aoki and M. Ichimaru) on August, 20 that year and a third collision was observed by G. Hall from USA on September, 10 2012 after a report of a visual observation from D. Petersen from USA. Credit: Hueso/Wesley/Go/Tachikawa/Aoki/Ichimaru/Petersen
Simulations of object entering Jupiter's atmosphere. Credit: Jarrad Pond/South Florida University.
About the European Planetary Science Congress (EPSC):
EPSC is the major European meeting on planetary science. EPSC 2013 is taking place at University College London (UCL) from Sunday 8 September to Friday 13 September 2013. It is the first time that the Congress has been held in the UK. The 2013 program includes around 75 sessions and workshops. Details of the Congress and a full schedule of EPSC 2013 scientific sessions and events can be found at the official website:
EPSC 2013 is organized by Europlanet, UCL and Copernicus Meetings and the event is sponsored by the UK Space Agency, UCL, Astrium and the Science and Technology Facilities Council. To celebrate EPSC coming to London, a 'Festival of the Planets' has been organized across the Capital in collaboration with partners including the Baker Street Irregular Astronomers, the Bloomsbury Theatre, the British Astronomical Association, the British Interplanetary Society, the Natural History Museum, the Open University, Queen Mary University of London, the Royal Astronomical Society, Royal Museums Greenwich and University College London. http://www.europlanet-eu.org/epsc2013/outreach-activities
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Europlanet (http://www.europlanet-eu.org) is a network of planetary scientists, whose aim is to bring together the disparate European community so that Europe can play a leading role in space exploration. Europlanet's activities complement the mission activities of the European Space Agency through field work at planetary-analogue terrains on Earth, laboratory measurements, computer modeling and observations from ground-based telescopes. Founded in 2002 and funded by the European Commission from 2005-2012, Europlanet has evolved into a community-based organization that will carry on this work and plan for future missions and mission support.
About UCL (University College London):
Founded in 1826, UCL (http://www.ucl.ac.uk) was the first English university established after Oxford and Cambridge, the first to admit students regardless of race, class, religion or gender and the first to provide systematic teaching of law, architecture and medicine. UCL is among the world's top universities, as reflected by our performance in a range of international rankings and tables. According to the Thomson Scientific Citation Index, UCL is the second most highly cited European university and the 15th most highly cited in the world. UCL has nearly 27,000 students from 150 countries and more than 9,000 employees, of whom one third are from outside the UK. The university is based in Bloomsbury in the heart of London, but also has two international campuses -- UCL Australia and UCL Qatar. Its annual income is more than £800 million.