3. ROSAT TO CRASH BACK TO EARTH: UPDATE: The massive ROSAT X-ray space telescope is nearing a fiery burn-up in Earth's atmosphere. Most experts agree that re-entry will occur during the early hours of Oct. 23rd, but cannot predict the likely re-entry point yet. Observers report that the satellite, which of course is getting ever lower and closer, can be as bright as a first magnitude star and it occasionally "flares" to even greater brightness. For last-chance sightings of ROSAT in your area, check www.heavens-above.com, or SpaceWeather's online satellite tracker (http://spaceweather.com/flybys) or turn your smartphone into a ROSAT tracker: http://simpleflybys.com .
In case you missed the last alert, here are the relevant points from that one:
The ROSAT X-ray astronomy observatory is smaller and less massive than NASA's Upper Atmospheric Research Satellite, or UARS, which fell back to Earth on Sept. 24. But officials predict it will spread three times more debris and pose a greater threat to people than UARS. That's because ROSAT is made of heat-resistant components, especially its primary mirror, which officials say will probably be the largest single fragment that will reach Earth. The satellite will streak into the atmosphere at 17,000 mph, and temperatures up to 3,000 degrees Fahrenheit will burn up much of the spacecraft.
All these forces exerted on the satellite cause it to disintegrate, which in turn means that it eventually lands in the form of a long debris trail. The really heavy objects land later, because they ultimately have to drill their way through the atmosphere."
The bulk of ROSAT is expected to survive re-entry, littering its impact point with up to 30 pieces of debris. There is a 1-in-2,000 chance someone will be struck by fragments of ROSAT on its way down, according to German scientists. That's odds of about 1-in-14 trillion that any individual person will be hit. However, ROSAT will likely end up in the sea, like UARS last month.
Even one day before re-entry, the time of ROSAT's demise will only be known with a precision of plus-or-minus five hours, putting entire oceans and continents in the satellite's flight path. It will not be possible to make any kind of reliable forecast about where the satellite will actually come down until about one or two hours before the fact. It will, however, be possible to predict, about one day in advance, which geographical regions will definitely not be affected.
The slow descent is due to the friction encountered by the satellite as it enters the outer fringes of Earth atmosphere, which increases the more ROSAT penetrates into our atmosphere. Fluctuations in solar activity affect the upper atmosphere and thus can quicken or slow a satellite's re-entry.
We want to ensure that students all over the world have the opportunity to compete in this exciting competition, and we want your help in letting them know about it. Please help us in communicating the announcement of YouTube Space Lab to your educational networks as widely as possible. There's much more information about the competition online on the channel and there is also a site especially for teachers to help on how to approach getting students involved in YouTube Space Lab. Thank you for your help in making the world's largest, most global and inclusive space competition a huge success!
The YouTube Space Lab Team
P.S. Please feel free to forward this to educators or educator networks you know!
The best photo opportunity will probably occur on the evening of Oct 22/23 when Palma will lie between the core of M 31 and M 110 (NGC 205). The following evening (Oct 23/24) it will pass some 13' south of Messier 110.
A finder chart (courtesy of Graham Relf of the BAA Computing Section) showing the general path of Palma is available at: http://britastro.org/computing/ch/372Palma2011Oct21(J2000).png. N.B. It will be necessary to take a time-series of images and stack these
to show the trail of the moving asteroid as its apparent speed is only 34" per hour.
7. MARS SCIENCE LABORATORY TALKS: Kevin Nolan, very well-known in Irish astronomy circles, will be giving a new talk titled "Mars Science Laboratory: In search of Origins" to celebrate the Science Week Theme of "The chemistry of life" and the launch of MSL-Curiosity the week after (On November 25th). Kevin is the Irish Representative of The Planetary Society, and is the author of an excellent book on Mars; "Mars, A Cosmic Stepping Stone", published by Springer. (See the great reviews at http://www.amazon.co.uk/Mars-Cosmic-Stepping-Stone-ebook/dp/B001VNCFBC)
He will be giving the same talk three times - in Dublin (Mansion House on Monday 14th), Galway (NUI Galway on Nov 16th) and Blackrock Castle Observatory (Friday November 18th).
Kevin adds: "On a related note, I have just launched the new Planetary Society Ireland web site at www.planetary.ie.
It's quite basic now but is being used to promote the talk at www.planetary.ie/msl. I've also created a new twitter account @planetarie and will be tweeting in selected areas of TPS News, Space News and Policy issues, Mars Exploration and Irish Astronomy matters. While I have few followers just now, Forfas-DSE, BCO and nightsky.ie are retweeting my tweets and these, along with other mechanisms such as the talks in November and an intended blog (planetarie.wordpress.com for 2012) I hope to build a following. I will always be delighted to tweet any IAA news that you need further circulation on (as and when I develop a following!!)."
8. TWITTER: the IAA now has a twitter account. twitter@IaaAstro