Spring Sale DVD Membership Shop World-Class Speaker: "Threat From Space" It's not often that Astronomy Ireland can get a world-class speaker to come and address you in Ireland so I wanted to make sure you come along (or order the DVD) and hear Jay Tate speak next Monday, and try to bring as many friends as you can as it's a fascinating "popular level" talk. The threat from space is very real. Every year we estimate two small rocks from space land on Ireland. Few are found but major fireballs light up the sky several times as year. Larger objects are less common and a "dinosaur-killer" (roughly 10km across) comes along every 100 million years. So far, a survey has been done to find most of the 1,000 or so 1km or larger rocks in space that might his us and 1950 DA is biggest threat known but it will not come close until 2880 AD. But a half kilometre asteroid would cause untold devastation and a survey to find all objects 150 metres across won't be completed until 2020, and there are a lot more of them. Even in 2020 even this survey is complete there were at least two 50 metre sized objects that struck the Earth causing significant damage. The famous Tunguska event in 1908 which flattened 2,000 square kilometres (about the size of one Irish county) of forest, fortunately it hit an unpopulated in Siberia, but had it hit 5 hours later it would have destroyed the city of St. Petersburg killing millions. And remember, a 50 metre size object has 27 times less material in it than the 150 metre objects being surveyed. At least we can predict asteroids if well into the future. Comets come from much further out and there could be perhaps half as many of those that threaten us, and no survey would help us. We'd need a system in place today to respond to such a threat. So, many people say we are wide open to the threat from space, and we will be for a long time to come. It's hardly surprising then that some scientists are trying to highlight the threat, gauge how big the threat is, and do something about, while we have time. Jay Tate is a world leader in all this so his talk next Monday will be fascinating, thought provoking, and bring you right up to date with the threat and what can be done. It will obviously have mass appeal so please circulate this notice and why not book several tickets for yourself and friends, or order the DVD (same price as a ticket) today and watch the talk that way. BOOK TICKETS and/or DVD HERE See you there! David Moore Astronomy Ireland Chairman, and Editor "Astronomy Ireland" magazine Astronomy Ireland The world's most popular Astronomy Club www.astronomy.ie ( subscribe / unsubscribe )