A new study has confirmed amateur astronomers recorded a pair of small meteors impacting with the planet Jupiter, highlighting the growing value of amateurs to the field of astronomy.
The impacts struck the giant gas planet on 3 June and 20 August, lasting only a couple of seconds.
An international team of astronomers led by Dr Ricardo Heuso from the Universidad del País Vasco, Spain will publish the results of their analysis of the earlier impact in an upcoming edition of The Astrophysical Journal Letters.
The June impact was captured on video by amateur astronomers Anthony Wesley from Murrumbateman, New South Wales, and colleague Christopher Go in Cebu, The Philippines.
Wesley, who was also the first to spot a large, long-lasting impact on Jupiter in July 2009, says he feels "very lucky".
"I got into this [observing] not expecting to get anything else but high quality images of Jupiter and Saturn," says Wesley.
He says the ability of amateur astronomers to contribute to professional astronomy has changed "even in the past few years" as high speed video and telescope technologies improve.
"We can't compete with professional astronomers, but we can do a lot of direct observations. There's a lot of science that can be done with smaller telescopes," he says.
A second impact on Jupiter was detected last month by Japanese amateur astronomers Masayaki Tachikawa and Aoki Kazuo.
The systematic recording of such events could help to quantify the threat of similar-sized objects hitting the Earth, says Heuso.
Travelling at about 60 kilometres per second, the June meteor struck Jupiter's atmosphere with an energy of around one thousand million million Joules.
This is five to 50 times less than the impact that destroyed forests in the Tunguska regio of Siberia in 1908. The August impact is thought to be of similar size.
Because of its large size, Jupiter is a magnet to asteroids and these impact events appear to be common quite common.
More to come
Heuso say, professional astronomers aren't focussed on Jupiter and Saturn every night and therefore been missing out.
"A new observing field for Jupiter amateurs has been opened," he says.
"The small impact on Jupiter detected by Anthony Wesley was the first one to ever be detected while it was happening. Before this impact small impacts outside the Earth observed from our planet have only been seen directly once on the Moon.
Heuso says now that astronomer know what to expect, he believe many more impacts will be discovered by amateurs in the future.
"The instruments in professional observatories are not optimised for this research and progress in this area will only come from amateurs and their collaboration with professional astronomers to put the impacts into a science context."