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THE REFLECTOR Volume 5, Issue 8 November 2006 Editorial

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THE REFLECTOR Volume 5, Issue 8 November 2006 Editorial ISSN 1712-4425 PETERBOROUGH ASTRONOMICAL ASSOCIATION THE REFLECTOR Volume 5, Issue 8 November 2006 Editorial he month of October wasn’t very T good for observing, but despite all of that rain there were some high points. Astronaut Chris Hadfield gave a couple of talks in Peterborough on October 26th. In this issue of the Reflector is a picture of our PAA President getting an autograph! At the October 27th PAA meeting we had Steve Dodson for a guest speaker. He talked about his work in astronomy and intrigued us with the mysteries of our universe. Check out an article on all of this and more on pgs. 8-9. Shawna Miles [email protected] Cassiopeia A. taken by the Spitzer Space Telescope. Image credit: NASA/JPL/ Caltech remnants would be mixed and mashed When Cassiopeia A exploded, most Supernova Remnant together in one big cloud. of the original layers flew out in succes- sive order, but some layers went out fast, Finally Explained During the supernova, as the layers while others moved at slower speeds, shot outward, they hit the shockwave depending on where they started. t’s name is Cassiopeia A. The star from the explosion. Materials that hit I was 15 to 20 times the mass of our the shockwave first have had more time For more information go to:http:// Sun. It is located in the Milky Way gal- to heat up into X-rays and visible light. www.nasa.gov/mission_pages/spitzer/ axy, and exploded relatively recently. For We have been able to see these, but main/index.html or http:// years astronomers have been trying to Spitzer has allowed for us to see the www.spitzer.caltech.edu/spitzer figure out how this supernova remnant missing pieces. The material that is was created. The Spitzer Space Tele- now hitting the shockwave are cooler Shawna Miles scope has now helped to solve the mys- and create infrared light, which Spitzer [email protected] tery. can detect. Spitzer has helped astronomers to Inside This Issue understand what happened when Cassio- peia A blew up. The original star was q EDITORIAL q SUPERWASP FINDS PLANETS made up of ‘shells,’ with the lightest ele- BEYOND OUR IMAGINATION ments in the outer shells and the heavier q ALOHA #7 - W.M KECK q CANADIAN SPACE-WALKER MUSES elements in the center. Spitzer’s new OBSERVATORY ON “THE SMELL OF SPACE” photographs show that the Cassiopeia A remnant is made up of shells, just like the q HUBBLE IDENTIFIES MORE q NASA SPACE PLACE - DEADLY star. This tells astronomers that the ex- EXOPLANET CANDIDATES PLANETS plosion was not chaotic, otherwise the q THE SKY THIS MONTH q MEETING NOTES Page 2 THE REFLECTOR about 2,000 times greater than a single The planet is known as HAT-P-1b SuperWasp Finds telescope and can monitor the entire and orbits a star 450 light years from Planets Beyond Our local sky several times per night. One Earth in the constellation Lacerta. With a snapshot captures hundreds of thou- girth that is 36% larger than our own Imagination sands of stars for analysis. Jupiter, it is the largest exoplanet found to date. But big doesn’t mean brawn in The SuperWasp system detects this case. HAT-P-1b is only half Jupiter’s f you’ve kept pace with the astro- faint dips in the light from distant stars. density, or about one-quarter that of wa- I nomical community’s search for plan- This can be caused by a planet orbiting ter (the density of a cork). ets orbiting distant suns should be pretty in front of it. To find our two super Yet as weird as HAT-P-1b may seem to blasé about their numbers – 200+ at last Jupiters, Project SuperWasp monitored be, there are others like it – including the count. But check the specs on some of just over a million stars. first exoplanet ever discovered in 1999 in these far-out worlds and the word the constellation Pegasus. We’ve come a “incredible” is an understatement. Once SuperWasp had tracked down long way since – but instead of answers, a batch of likely candidates, the data we just pile up more questions. In 2004 two Hot Jupiters were dis- was transferred to the project’s French covered orbiting stars 1,000 light years counterparts at the Observatoire de Until we meet again, keep the lights and 500 light years away in the constella- Haute-Provence. Here another method down dim and the stars up big and bright. tion Andromeda. Their discovery came of detecting extrasolar planets is em- You’ll save energy, money, and the dark about thanks to a British project nick- ployed to confirm SuperWasp’s find- Kawartha night skies. named SuperWasp. ings. Again, highly sensitive equipment monitors the stars. But instead of look- John Crossen Using highly sensitive equipment ing for dips in the stars magnitude, this [email protected] Project SuperWasp scans the sky with a system (called Sophie) detects little battery of 8 scientific camera lenses gravitational tugs on the star. These 11cm in diameter. They are stacked in a tugs confirm that something is orbiting robotic fork mount that tracks the night the star and pulling on it – ever so sky. This system has a field of view slightly. Aloha#7 – W.M. Keck Once the existence of the two extra- Observatory solar planets was confirmed, other tele- scopes such as the Spitzer and Hubble (Keck I & II) space observatories track down further data. So what do we know about our two new Hot Jupiters now that we t the 13,647 ft (4,160 m) altitude know where they are? A level, there are two optical/infrared telescopes side by side, each with a 33 ft Both orbit their suns at a much (10 m) diameter mirror, housed in twin closer distance than our Jupiter does. 101 ft (30.8 m) high by 121 ft (37 m) These big boys swing around their stars wide domes. The mirrors are each con- in less than three days. Distant Jupiter structed of 36 hexagonal segments (6 takes 12 years. Being so close to their ft/1.8 m wide and 3 in/7.5 cm thick). star also makes them very hot. Both They are so finely polished that if each have an estimated surface temperature mirror segment were expanded to the of about 1,800C. For comparison, our width of the earth, the highest elevation sun’s surface temperature is 6,000C. would only be 3 feet high (less than a meter)! Each segment is manipulated to But that’s normal compared to the help the whole mirror operate as an ef- suspicion that the clouds on these two fective single unit. Computers control hotties are made from rock snowflakes. the tweaking of each mirror segment That’s because the types of clouds that twice every second. This results in an SuperWasp detects hundreds of thou- condense at these high temperatures are accuracy of 4 nanometers (about 25,000 sands in a single snap-shot. One made of elements that we normally times thinner than a human hair). Now night’s observing run generates up to think of as minerals – olivne, forster- that is precise optics. 60 GB of data. Project SuperWasp is a ite, and other magnesium silicates. UK/France initiative with camera sys- Moving from rock clouds, we now en- The Keck I telescope has confirmed tems in the Canary Islands and South counter a real mush-ball. the discovery of more extra-solar planets Africa. Continued... Page 3 THE REFLECTOR Canadian Space- walker Muses On "The Smell Of Space" It's always funny to hear astronauts mak- ing small-talk. How - I always wonder - can the traffic on the way to a public appearance or the latest episode of Lost compare with floating free in the vacuum of outer-space. It was this thought that was going through my head after Canadian astro- naut and STS-115 spacewalker Steve MacLean finished up an interview for Daily Planet and DiscoveryChannel.ca in CTV's Scarbourgh studios. In addition to (more than 50) than any other ground How did the Keck Observatory get doing a TV interview with Jay Ingram based telescope. Keck I & II can be used it name? William Myron Keck (1880- for the show, Jay was nice enough to tip together for the same effective resolution 1964), the founder of The Superior Oil me off to Steve's appearance and the fact of a 279 ft (85 m) telescope. Keck also Company, established the W.M. Keck that we might want to have him do some claims to have recorded the most distant Foundation in 1954. This foundation "bonus" questions for the web site, which object known to astronomers (galaxies at has always supported imaginative inno- he would ensure the asking of (being the 14 bly). vations for new scientific discoveries host and all makes this an easy promise and technology, so it only seems fitting for him to make.) NASA and Cal Tech run the facility, that these two unique telescopes carry which opened Keck I in 1992, and Keck the name of a foundation that stands for After Daily Planet's interview with a II in 1996. They are the classic “dome” what they accomplish. North Korean nuclear program expert got shaped and are striking in comparison to bumped over, Steve finally ended up the unconventional Subaru design. Dur- The control centre for the Keck sitting down in our studio (formerly the ing weekdays, Keck I is opened to tours domes is not located in Hilo, like most studio for the Dini Petty Show, for the from 10 to 4.
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