<p>The comet Siding Spring that buzzed past Mars Oct 19 caused an intense meteor shower and added a new layer of ions, or charged particles, to the ionosphere, NASA said.<br /><br /></p>.<p>The effect of the comet on the Martian atmosphere was detected by two NASA spacecraft, including the MAVEN mission and an European spacecraft.<br /><br />The ionosphere is an electrically charged region in the atmosphere that extends about 120 kilometres to several hundred kilometres above the Martian surface.<br /><br />Using the observations, scientists were able to make a direct connection between the input of debris from the meteor shower to the subsequent formation of the transient layer of ions - the first time such an event has been observed on any planet, including Earth, said the MAVEN research team.<br /><br />"They call this comet encounter a once-in-a-lifetime event, but it is more like once-in-a-million years," said Nick Schneider, scientist with the MAVEN mission and associate professor at the University of Colorado, Boulder in the US.<br /><br />"The numbers suggest a Martian would have seen many thousands of shooting stars per hour - possibly enough to be called a meteor storm - so it must have been a spectacular event that night on Mars," Schneider added.<br /><br />The comet travelled from the most distant region of our solar system called the Oort Cloud and made an approach within 139,500 kilometres of the Red Planet.<br /><br />That is less than half the distance between Earth and our moon and less than one-tenth the distance of any known comet flyby of Earth.</p>
<p>The comet Siding Spring that buzzed past Mars Oct 19 caused an intense meteor shower and added a new layer of ions, or charged particles, to the ionosphere, NASA said.<br /><br /></p>.<p>The effect of the comet on the Martian atmosphere was detected by two NASA spacecraft, including the MAVEN mission and an European spacecraft.<br /><br />The ionosphere is an electrically charged region in the atmosphere that extends about 120 kilometres to several hundred kilometres above the Martian surface.<br /><br />Using the observations, scientists were able to make a direct connection between the input of debris from the meteor shower to the subsequent formation of the transient layer of ions - the first time such an event has been observed on any planet, including Earth, said the MAVEN research team.<br /><br />"They call this comet encounter a once-in-a-lifetime event, but it is more like once-in-a-million years," said Nick Schneider, scientist with the MAVEN mission and associate professor at the University of Colorado, Boulder in the US.<br /><br />"The numbers suggest a Martian would have seen many thousands of shooting stars per hour - possibly enough to be called a meteor storm - so it must have been a spectacular event that night on Mars," Schneider added.<br /><br />The comet travelled from the most distant region of our solar system called the Oort Cloud and made an approach within 139,500 kilometres of the Red Planet.<br /><br />That is less than half the distance between Earth and our moon and less than one-tenth the distance of any known comet flyby of Earth.</p>