Star - Bintel
Transcription
Star - Bintel
Tele Vue Published monthly by Published monthly since 1985 The Binocular and Telescope Shop by The Binocular and Telescope 55 York Street, Sydney NSW 2000Shop 55 York Street, Sydney NSW 2000 OCTOBER 2004 * Volume 232 www.bintel.com.au the best NEW ASTRONOMY MAGAZINE SKY & TELESCOPE ‘AUSTRALIAN EDITION’ American Sky & Telescope has announced plans to produce an Australian version of its monthly magazine, beginning almost immediately. In a deal that has taken almost a year to stitch together, local company Paragon Media Pty. Ltd, has agreed to produce eleven issues per year with a percentage of local content and local advertising. Managing Director of Paragon, Ian Brooks together with Publisher Todd Cole have previous experience with large-scale magazine production. They are already lining up experienced staff to help produce the first Australian issue of the magazine which should be on the shelves at the newsagents in early December in time for Christmas sales. “We plan to help grow the market. “ says Ian Brooks. “Given the respect this title receives, we are confident that it will rapidly find a following in astronomy and science circles, then attract the attention of the general public.” Sky & Telescope has been published by Sky Publishing in the USA since 1941 and is a well-known market leader. Current issue of Sky & Telescope from the USA VIRGIN ASTRONAUTS . . . BRANSON SIGNS DEAL WITH RUTAN Sir Richard Branson announced in late September that the Virgin group has signed a deal with Paul Allen and Burt Rutan. The effect of the agreement will be that a new company Virgin Galactic will offer the world’s first commercial passenger flights into space.... possibly within the next two or three years. SpaceShipOne, (shown on the left with the Virgin logo superimposed) was funded by Paul Allen, co-founder of Microsoft with Bill Gates. The design and construction was by aircraft inventer Burt Rutan, famous for his revolutionary canard wing designs and in the use of foamcored fibreglass shapes for home-built light aircraft. Rutan also designed the light aircraft Voyager, which circled the globe non-stop and unrefuelled in 1987. Voyager took off from Mojave airport in California carrying two pilots, Dick Rutan and Jeanna Yeager into the history books. It flew 42,200 km in just over nine days and used approximately 3200kg of fuel. The aircraft itself weighed just 450kg due to the use of carbon composites and other super lightweight materials. Burt Rutan said, on the signing of the historic deal that he believed that the consortium would be able to develop the finest suborbital operation system possible. The first flight of SpaceShipOne, although not perfect, included several new technologies that address the cost and safety of manned space flight. By designing a craft that uses its own wing and tail system as a brake for slow re-entry into the atmosphere, Rutan avoided the problems associated with high-speed, high-temperature re-entry. The destruction of the space shuttle Columbia and its crew of seven astronauts in February 2003 highlighted the potential for disaster in high speed re-entry. SpaceShipOne makes second successful space flight . . .. . just ! SpaceShipOne made its second successful flight into space on September 29 from its base at the Mojave desert, California. In front of a large crowd of onlookers the craft was carried aloft, slung under the belly of its mothercraft, WhiteKnight. At an altitude of 17,000 metres the spacecraft was dropped from WhiteKnight. Pilot Mike Melvill ignited the rocket motor, a hybrid system that uses Nitrous Oxide as an oxidiser and hydroxy-terminated polybutadiene (HTPB or rubber) as the solid fuel. The craft accelerated through the sound barrier on its ascent. Halfway into the ascent the craft began a slow roll which developed into a rapid roll, causing anxiety in observers on the ground. It appeared for several seconds that the craft was out of control. The motor was cut, the flight reverted to smooth climb and SpaceShipOne coasted to 103 kilometres altitude, just over the limit required. The craft then nosed over and deployed the tail as a drag device to slow its return. After a slow descent the tail was reconfigured from the ‘shuttlecock’ position and glided smoothly down to a perfect landing. No passengers were carried but an equivalent weight was loaded aboard to comply with the Ansari X requirements. At a debrief after the flight pilot Melvill said, "At the top, I got a surprise, the ship Mike Melvill waves after flight. really spun up and did a little victory roll. We got a little bit of a rolling motion going,"" He believes that he may have over-corrected, causing the wild gyrations. "That sort of thing can happen at my age!". He added that SpaceShipOne " ... flies like a dream. It's Les Sara Les Sara a real Burt Rutan special." At a news conference later, Melvill said the flight began normally but he probably touched the controls when he shouldn’t have. Other than the pilot-induced problem the flight was normal. The spacecraft will probably be prepared for another flight within a week. If this is successful the prize will be won, leaving a dozen other teams struggling in their wake to be second. However as they say, there is no prize for second place. AMATEUR STRONOMERS X-RATED ON INTERNET! We ourselves find this hard to believe .... but it has happened! An amateur astronomer forum on the internet has had an “Adults Only” rating slapped on it by Yahoo. The group, which discusses all manner of subjects related to the use of telescopes has suddenly found that it is restricted to ‘adults only’ and have been unable to find out exactly why this has happened. There are suggestions that some of the topics they discuss, “...piggyback mountings... bare wiring... Uranus... and other similarly disturbing ideas, including very clear references to “naked eye viewing...” have tripped switched somewhere in the Yahoo system which has moved the group to an age restricted area from the “science, astronomy, amateur space area” they were in before. Members have attempted to contact Yahoo regarding this error but have had no success as yet in rectifying the mistake. We’d like to mention the name of the group but we are advised that, as this newsletter goes out to schools, it is best to not reveal the name in case the site is inundated by young people intent on viewing ‘naked eyes’, ‘piggyback mounts’ and other unseemly devices. We dare not take part in a perverted attempt to lower the morals of our teenagers and younger astronomers. There is a backlash (maybe we shouldn’t even use that word...) as fundamentalists, creationists and flat-earthers take up arms against science. Television stations are already being pestered to remove scientific programs and anything else involved in truth and reality. It’s on till December! The great Tele Vue sale! . . . . . . . . . . . . . . . . . . . . check the new lower prices at www.bintelshop.com.au . . . . . . . . . . . . . . . . Watery skies; Mel explains ...........2 AstroSpeak; using the language...2 Star Map for October ...................3 Mick ‘n Don .......................... .......4 SUBSCRIBE TO THE NIGHT SKY FOR $12 Receive your copy every month for an eyeful of sky news . A plaintive cry for help has been received from a budding independent politician to fund his campaign for election in the federal seat of Cook. Graeme Strang has a Celestron CM-1100 telescope that gets little use these days as he spends most of his days (and nights) developing his interesting theories on zero taxation replaced by a land and resource rent. Anyone interested in snapping up a large telescope or hearing about a different method of funding the nation’s activities could contact Graeme on 02 9580 1491. ★ ★ ★ Graeme stood in the last election and was beaten by a mere 41,536 votes by the sitting Member Bruce Laird, seven other cantidates and the donkey vote. ★ ★ ★ After months of rumours the cat is out of the bag. Sky and Telescope, the American astronomy magazine is to launch an Australian edition. The Australian edition should be on the streets by Christmas. We live in interesting times. ★ ★ ★ Internet Telescope Forum classified as “Adults Only”? I kid you not! It has indeed happened. Well, what do you expect when amateur astronomers talk about “naked-eye observing” ... “piggyback mounting” and other questionable practises? What are we coming to? ★ ★ ★ What with Full Moon and all . . . . the doom and destruction crowd became somewhat agitated at the prospect of the world’s impending destruction at the hands of asteroid Toutatis. Maybe they are becoming bored with their own cries of ‘wolf, wolf’! You can only claim that the world is ending a few times before nobody will listen. See the prognostications of one of Australia’s predictors of doom and gloom on Page 2. If she’d been right just a few times there would not be many of us left to read this. ★ ★ ★ When Harry Roberts, an amateur astronomer announced that he could detect ‘blue-shift’ on solar flares his news was treated with scepticism. Now however ......., see Page 4. ★ ★ ★ Greg Cantori, an amateur astronomer in the Sydney region is a long-term reader of this newsletter. He claims to have read every issue from the first in 1985. He complained that his name has never appeared in print in the NIGHT SKY. Well Greg, here’s your 15 minutes of fame! The Binocular and Telescope Shop, 55 York Street, Sydney. Tel: 02 9262 1344 web: www.bintel.com.au ‘STARGAZER’ BOOK LAUNCHED IN STORE Spring has sprung! The warm weather means that nights are not so M2 (NGC 7089) is a globular cluster cold. October is the full last month lying 37,000 light years away. At before daylight savings kicks in. magnitude 6.5, it can be easily seen Now is the time to get out and enjoy in binoculars or small telescopes, the last of the Winter constellations however to resolve the brighter stars as well as some of the fainter Spring a telescope of 100mm or more is constellations. One of the fainter and required. NGC 7009 (the Saturn most ancient constellations in the sky Nebula) is a planetary nebula lying is Aquarius. Currently the Sun is in about 3,000 light years away. It Aquarius from late February to early resembled the planet Saturn when March, however in the future Aquarius will one day contain the vernal equinox (the point Fomalhaut when the Sun crosses into the northern hemisphere each year). This will not occur until AD 2597 when the point will Helix Neb δ move from Pisces to Aquarius. Astronomically, this is very important as the right ascension coordinate measurements are taken from ι this point. ζ Aquarius is one of the few constellations that has carried a consistent mythical theme across different α β cultures. To the Greeks, the constellation represented Saturn Neb Ganymede, a young shepherd who was carried off by Zeus M2 to be the wine-waiter to the AQUARIUS gods. The Babylonians saw a man pouring water from a jar and the Egyptians saw the figure as viewed through large aperture Hapi, the god of the Nile, his urn telescopes. At 8th magnitude, it appears as a blue/green ellipse and symbolising good fortune. Aquarius mostly consists of can be seen in telescopes 75mm or relatively faint stars, with its brightest greater. October also sees the return star magnitude 2.9, thus making the constellation harder to see in light of the annual Orionids meteor polluted skies. However, Aquarius shower. Interestingly, this shower was first recorded in 288AD by has some dazzling sights: Alpha (α) Aquarii is a yellow Chinese astronomers. Meteor supergiant, shining at magnitude 2.9 showers are caused when the Earth crosses the orbit of a comet and and lying 760 light years away. Beta (β) Aquarii is also a yellow encounters a trail of debris and dust supergiant with the same magnitude left by the comet. Certain meteors as Alpha Aquarii. Beta Aquarii is a showers can be attributed to particular comets and the Orionids little closer to us than Alpha. Zeta (ζ) Aquarii is a well-known are associated with Halley’s Comet. binary consisting of 2 white stars at Meteors are best seen after midnight, magnitudes 4.3 and 4.5. Their orbital with the Orionids no exception. The period is 760 years and currently they shower is active from October 2 until are moving apart, making them an November 7. Maximum occurs on October 21. However the Orionids easy target for small telescopes. M72 (NGC 6981) is a globular also experience many subcluster, however at 9th magnitude maximums that occur around this and a distance of about 56,000 light date. The last two decades have produced good rates of from 14 to years. NGC 7293, the Helix Nebula is the 31 meteors an hour which means that closest planetary nebula to the Sun observations of this shower should The Helix covers about a quarter of certainly be worth the effort. The a degree of the sky, thus making it Orionids are usually bright and swift, the largest planetary in apparent size. moving at approx. 66 km per second In recent years Hubble Space with many leaving glowing trains. telescope has taken close-ups Ensure you make the most of the revealing small knots of molecular night hours this month and enjoy gas dubbed “cometary knots” due to some of the Spring delights our Universe has on show! their appearance.. THE MILKY WAY Left: Customers queue for sales and refreshments at the B & T Shop . Right: Professor Fred Watson busily signing copies of his book . Below: Nadia Douglass watches carefully as Professor Fred Watson signs one of six copies she bought. Below: The book itself. Cover depicts Atlas holding up the sky Dr Fred Watson’s new book “Stargazer, the life and times of the telescope” was given a cheerful introduction to the book-buying public at The Binocular and Telescope on 23rd September. Fred was installed at a desk in the store in the late afternoon and sat there chatting with customers, signing and inscribing copies of the book for almost three hours! In the meantime amateur astronomers and book-buyers from as far afield as the Blue Mountains chatted, consumed several bottles of commemorative “Fred’s Coice” Cabernet Merlot and Semillon Chardonnay and munched their way through trays of finger foods and sandwiches. It wasn’t till 8.30pm when the last book was signed, the last Cabernet Merlot quaffed and the last customer ushered out the door that Fred was allowed some rest before being taken off for a well-earned dinner by Glen Dawes of Quasar Publishing. An eminently readable book, “Stargazer” will make an excellent addition to the bookshelf of the person interested in the history of astronomy. October 2004 * Volume 232 * Page 2 ASTRO-SPEAK an observer’s dictionary. . . . More language from Jack Kramer’s “Guide to Astrospeak, the amateur astronomer’s dictionary”; Cruise Control: a clock drive on a telescope mount. Dew dads: droplets of water that form on telescope surfaces. Dob Snob: an amateur astronomer who considers Dobsonian telescopes superior to all others. Faint fuzzies: celestial objects whose name begins with NGC, IC or Messier. Fuzzy friendly: a good dark sky site. Fuzz finder: a person who prefers looking at very faint objects. Gotit!: An exclamation that indicates that an observer has found a faint fuzzy Gunky: cloudy (the sky was .....) MZero: When an observer can see nothing. Nailed it!: To definitely see a faint fuzzy. Diddly Squat’s Nebula: An empty hole in the sky. MACQUARIE UNIVERSITY ASTRONOMY OPEN NIGHT Saturday 23 Oct 6pm till 10pm North Ryde kids welcome ! CLOSE ENCOUNTER WITH ASTEROID BUT WORLD DOES NOT END THIS TIME Doomsayers have been busy claiming that the asteroid Toutatis could possibly strike the earth causing mayhem, death and destruction. Wild claims were made that NASA (why always NASA?) knew the risks but was refusing to inform the world. As you are reading this we can confidently suggest that Toutatis passed by the earth without inflicting casualties. One doom-sayer, possibly a figment of somebody’s fevered imagination is supposed to be an Australian, a Mrs Phipps-Earl. She is claimed to have predicted late in 2003 that the following would occur in 2004: “There will be four substantial earthquakes in Australia in the first five months of this year, Victoria, New South Wales and South Australia. NT and central Australia will have massive floods, many cut off completely. Northern Queensland will have several destructive cyclones and two in the Gulf, three in Northern WA. There will be a massing of sharks in Southern WA, many people attacked and many beaches closed. The bottom corner of WA will have a heatwave with little or no rain. There will be a gold strike in WA, many travelling to WA to make a fortune. South Australian grape crops for wine will be destroyed, one will be weather the other flying locusts, worst in history. Melbourne will have an earthquake, storms and major flooding. There will be a mystery illness, many taken to hospital. Sydney and North will experience an earth quake. Another major disaster in the Blue Mountains and a disaster will occur in the Sydney underground train system. Fires and gas leaks in Sydney, loss of water and power. Several States in Australia will experience substantial durations of loss of power and telephone. Severe drought and bush fires in South-West Queensland. Yet floods in Northern NSW up to Brisbane. Beaches washed away on Gold and Sunshine Coast. Water rushing in from the ocean up the Brisbane River, flooding inner city area. Major scientific discoveries made in Australia between now and August next year, three medical and one re space (the universe) which will involve a complete change in thought. Labour will win the next election.” .................. well, we’ll soon find out! Queensland amateur astronomer Eddie Trimachi took this impressive image of the Milky Way galaxy from Norma to Ophiuchus at the recent Queensland Astrofest. Eddie used his SBIG ST-10 CCCD imager with a 50mm Asahi Pentax lens. The panorama is a composite of 28 images laced together. Each image consists of six 5 minute exposures using a Ha 10nm Schuyler filter. More details: eddiet@astroshed.com.au The Binocular and Telescope Shop, 55 York Street, Sydney. Tel: 02 9262 1344 web: www.bintel.com.au October 2004 * Volume 232 * Page 3 you can now shop on-line at www.bintelshop.com.au for astronomical telescopes Mid-evening mid October 2004 The Moon’s appearance for the month of October is shown thusly: 6th 6 th Mercury is behind the un early in the month. Later it reaches the evening sky setting an hour after the Sun. Saturn is in Gemini and makes a neat line with Castor and Pollux. Look for it around 3am in the North East. Venus rises around 4am. and is the brightest object in the pre-dawn eastern sky. . Uranus is in Aquarius high in the western sky. Difficult to find. Last Quarter Moon at apogee 14th New Moon 22nd Perigee 23rd First Quarter 28th Full Moon Ralph Baldwin proposed that lunar craters were formed mostly by meteor impacts in 1941. Most astronomers at the time dismissed his theory. They now agree with him. Mars is too low in the eastern dawn sky to be seen easily. Patience! Wait till Christmas for better views. Jupiter is rising in the bright pre-dawn sky at the beginning of the month. By the end of October Jupiter is much more easily seen, especially as brighter Venus is now near the giant planet. Neptune is high in the West. Visually appears as a faint blue-green dot in telescopes. Pluto is having a whale of a time. Pollies are throwing porkies to the chooks (to mix metaphors) and Pluto is tearing around snapping lying ankles as fast as he can. Election time is great for a drover’s dog . Meteors are best seen after midnight, with the Orionids no exception. The shower is active from October 2 until November 7. Maximum occurs on October 21. However the Orionids also experiences many submaximums that occur around this date. The last two decades have produced good rates of from 14 to 31 meteors an hour which means that observations of this shower should certainly be worth the effort. The Orionids are usually bright and swift with many leaving glowing trains. Make sure you make the most of the night hours this month and enjoy some of the Spring delights our Universe has on show! The Orionids will be visible after midnight in the East. Look for the group of stars known as the ‘Saucepan’ or as some people call it the ‘Shopping Trolley’ . Want to see what has been described by one observer as a “celestial golf ball”? Located near the Small Magellanic Galaxy is a globular cluster of stars that goes by the interesting name of 47 Tuc. It can be found about fifty degrees above the southern horizon near the Small Magellanic Galaxy. Easy in binocs! The Binocular and Telescope Shop, 55 York Street, Sydney. Tel: 02 9262 1344 web: www.bintel.com.au FIRST LIGHT FOR CAS MEADE LX200 GPS 14” SCOPE CANBERRA Astronomical Macarthur Astronomical Society Inc: NSW ☎ (02) 4627 1424 Ian Cook. skyview@zipworld.com.au. Sutherland Astronomical Society Inc: NSW ☎ (02)9832 4082 Brett McMillan.www.sasi.net.au Northern Sydney Astronomical Society Inc: ☎ David (02) 9876 6750 www.nsas.ozau.net British Astronomical Association (NSW) ☎ 9398 9705 E. Cocking www.baansw.asn.au The Astronomical Society of NSW. ☎ (02) 4572 1568. Adrian Saw. www.asnsw.com The Western Sydney Amateur Astro Group Inc ☎ Dave Gault (02) 4754 4351 www4.tpgi.com.au/users/wsaag The Hawkesbury Astronomical Society: NSW ☎ (02) 4572 1568 Adrian Saw . The Wollongong Astronomy Club. NSW ☎ (02) 4261 9369 Paul Brown The Illawarra Astronomical Society: NSW ☎ (02) 4276 3199 Peter McKinnon Shoalhaven Astronomers: South Coast NSW ☎ (02) 4423 2255 Jack Apfelbaum www.shoal.net.au~astronomy/index.html The Astronomical Society of the Hunter: NSW ☎ (02) 4937 4664 Col Maybury colmay@kooee.com.au Newcastle Astronomical Society: NSW ☎ (02) 4950 0725 Allan Meehan www.nas.org.au Central West Astronomical Society, NSW Alex Abbey: abbeys@hn.ozemail.com.au. Port Macquarie Astronomical Association NSW ☎ (02) 6583 1933 Jim Daniels. Grafton Astronomical Society, NSW ☎ (02) 6642 4130 Jeff Ashenden Ballaarat Astronomical Society: Vic ☎ (03) 5332 7526 John Hastie http://observatory.ballarat.net Bendigo District Astronomical Society PO Box 164 Bendigo Vic 3552 . Barry McPhee Astronomical Society of Victoria Inc ☎ (03) 9888 7130. Linda Mockridge www.asv.org.au Latrobe Valley Astronomical Society Vic ☎ (03) 5174 6453 home.vicnet.net.au/~lvas Astronomical Society of Geelong, Vic ☎ 0407 345 070 Frank Baker for details. http://members.optushome.com.au/asog Mornington Peninsula Astronomical Society, ☎ 0419 253 252 Richard Pollard for details. Astronomical Society of Melbourne, Vic. ☎ 0412 - 318 125 Chris Ellis ngc4755@i.net.au Canberra Astronomical Society: ACT ☎ (02) 6288 7394 Diane Purcell. Brisbane Astronomical Society: Qld ☎ (07) 3321 8511 Darryl Mitchell www.bas.asn.au www.ozemail.com.au/~nwilliams/bas Southern Astronomical Society:Qld ☎ (07)5537 3852 Kevin Dixon. www.sas.org.au Astronomical Association of Queensland, Qld ☎ Peter Hall (07) 3378 1173 www.aaq.org.au South East Queensland Astronomical Society, ☎ (07) 3844 7904 Dave Larkin. www.powerup.com.au/~mcerlean/index.html Ingham Amateur Astronomers Club ☎ (07) 4776 5773 Tracey Castles. Bundaberg Astronomical Soc. Qld ☎ (07) 4159 7232 www.interwox.com.au Redlands Astronomical Society Qld ☎ (07) 3822 5545 Ross Spence Bundy Skywatchers (South-Central Qld) ☎ (07) 4159 9674 Karlene Galway Astronomical Society of South Australia, SA ☎ (08) 8338 1231 Tony Beresford. www.assa.org.au Astronomical Society of Tasmania, Tas ☎ (03) 6244 3476 Laurie Priest. www.ast.n3.net Astronomical Society of Alice Springs N.T. ☎ (08) 8952 9817 Annette Green Darwin Astronomy Group NT ☎ (08) 8945 9450 Phillip Smith Gove Amateur Astronomers, NT ☎ 0417 601 490 Ian Maclean for information. Astronomical Society of Western Australia, WA (now incorporating Murdoch Astronomical Society) http://aswa.info ☎ (08) 9299 6347 Val Semmler. Astronomical Society of The South-West, W.A. ☎ (08) 9721 1586 Phil Smith. Kim Rawlings, John Howard and Andrew White fire up the new Meade LX200. Society had all its belongings destroyed in the devastating fire that raged through Canberra on Saturday 19th January last year. Their library, records, computers and telescopes were at Mount Stromlo and were destroyed along with everything else on the mountain. Society members approached Meade Instruments in the USA to see if they could negotiate the purchase of a new 10” or 12” telescope at a reduced price. Meade contacted the Binocular and Telescope Shop and the upshot was that a brand-new LX200GPS 14” telescope was donated to the Canberra society on the basis that it would be permanently mounted in an observatory where it could be used for public education as well as for the Society’s research purposes. The telescope has since arrived and been temporarily installed in a dome where members can come to grips with the complexities of its operation. Society members have been buying books and other items to make up for the loss of the library that was reduced to ashes in the blaze that levelled hundreds of homes and almost every building and telescope at Mount Stromlo. The new telescope will be relocated to Mount Stromlo when its new home is completed. SEEING DOPPLER SHIFTS WITH Ha FILTERS! Harry Roberts We have all heard of the effects of “red-shift”, discovered in the early sixties, whereby the light of distant galaxies, and particularly quasars, is so reddened by their recession velocity that spectral lines located in the ultra-violet become visible in white light photos. Measurement of the red-shift allows the recession velocity of the object to be calculated; blue shifts of objects approaching the earth are also recorded The Lumicon H-alpha filter has a pass bandwidth of 1.5 Angstroms (A), and a 1 to 2 angstrom tuning range, either side of the central emission line at 6563A . It came as a surprise to find (after six months of observations) that the Lumicon H-alpha filter was capable of detecting both blue-shifts (often) and redshifts (occasionally) for high velocity ejection events that occur on the surface of the Sun. Observing with the filter, the user soon learns to recognise the dark sinuous features appearing on the solar surface, called filaments. These come in two kinds, Active Region Filaments (ARF) and Quiet Region Filaments (QRF)1 . The smaller ARF’s are found in clusters radiating from large sunspot groups (Fig 1). Both mark the boundaries between zones of different polarity. Although normally stable, both kinds of filament occasionally erupt, which causes flaring. Just before they erupt they grow dramatically darker (Fig 2), from grey to dense black over half an hour. Typically, around the time that flaring begins near the filament (Fig 2), the filament itself mysteriously disappears (Fig 3). The filament, of course, is a real object, perhaps 100,000 km long, containing millions of tonnes of matter; and can’t just disappear. The erupting filament, lifting off the Sun’s surface at huge velocity, say 50 to 100 km/second (~300,000 km/hr), has its H-alpha light (at 6563 A wavelength) shifted to the blue side of the band by the enormous speed of approach towards the observer. This shift is about minus1 Angstrom (A) for a velocity of 50 km/sec, and minus 2 A if the velocity of approach is about 100km/ sec.2 Since the pass band-width of most filters is around 1 angstrom, the blue shifted light will no longer pass the filter, and the approaching filament is therefore invisible. The Lumicon filter permits the observer to “tune” the filter by using a fine pitch tuning screw, allowing a shift of band width into the blue or red “wings” of the H-alpha waveband. There, in the blue “wing”, at 6562 or 6561A the observer will see the previously invisible filament (Fig 4). Of course, all other Halpha detail visible “on-band” is now unseen, although sunspots remain visible. In effect the observer is now viewing a very narrow red part of the white light Sun, as well as the Doppler shifted Halpha filament. Fig 5 shows how events might appear if viewed side on. This ability to “tune” into both blue and red ”wings” of the 6563 H-alpha band is a very desirable feature to have. It allows the user to search for material ejected towards or away from the observer, such as material streaming down onto the Sun’s surface in Post Flare Loops, or the enigmatic Surges, that can shoot backwards into the Sun!3 I suspect this wide “tuning” range is not available on competing sub-angstrom filters although I have NOT been able to test them. The sub-angstrom filters do produce higher contrast views of static surface phenomena. It is important to note that the Doppler effect can only be seen when the ejected material approaches or recedes from the observer along their line of sight. The effect is best seen near the centre of the Sun. Near the Sun’s limb there is very little motion along the line of sight, and no Doppler shift is seen. Doppler shifts can be detected almost every time a filament ejection and flare occur, but this can require a lot of observing. Direct observation of Doppler shifts is heaps of fun! I’m sure Einstein, who recognised the application of the effect to light beams while working up his Special Theory, would concur. 1 Zirin, H. “Astrophysics of the Sun”, Cambridge Uni Press. P 266. 2 Pasachoff, J. Field Memorial Professor of Astronomy, Ward College, personal comm. 3 Zirin, H “Astrophysics of the Sun”. p 299. If you’d like your Society included, please contact Mike Smith at (02) 9262 1344 or mike@bintel.com.au with information. We’ll put your details in the above list. Hey Don, why you carryin’ that umbrella? It ain’t rainin’. Mick, that big asteroid Toutatis has me worried. They say an umbrella will protect us against asteroid strikes. Er, a man can’t be too careful. Umbrellas also protect you from meteor showers. October 2004 * Volume 232 * Page 4 Bouncy Spring Quiz QUIZ Professor, His Eminence, Dr. Nervo Shatterini BGB, reports that the answers to the Winter Quiz are: (1) background radiation (2) Charon (3) Jupiter’s 11th moon. (4) William Lassell (5) NearShoemaker spacecraft. (6) Emission, reflection, dark. (7) crater on Phobos (8) An imaginary line joining centre of a satellite to centre of the parent body. (9) In a meteorite. (10) Tycho Brahe (11) Fred Hoyle (12) 47 Tuc (13) Vulpecula (14) Cetus (15) on the Moon. (16) crust of a planet or moon. (17) Neutral hydrogen. (18) Ernst Opik. (19) 1992 (20) 9,300km So many answers! So many mistakes! Best entry was from Kelly Belford of Ermington NSW. His Intrinsic Immenseness now presents his Bouncy Spring Quiz. Get to it quizaholics! (1) In what direction does a transit telescope move? (2) Where is the largest known caldera? (2) Who or what was the Leviathan of Parsontown? (2) Who discovered the dwarf companion of Sirius? (2) What part of Africa is recorded as a constellation? (2) What is the cosmological principle? (2) What metal does flint glass contain? (2) Where did the largest known stone meteorite fall? (2) Seth Nicholson discovered which moon? (2) What type of asteroids are bright and often slightly red? (2) What was the diameter of Newton's first telescope? (2) Which constellation lies between Cygnus and Andromeda? (2) Vulpecula contains which object you might see in a gymnasium? (2) Who invented the Coude telescope? (2) How much moon rock did astronauts bring back from the Moon? (2) Which ancient described a 'nebula following the sting of the scorpion? (2) In which year was the SOHO spacecraft launched? (2) Name an object in space that relates to a young frog. (2) What is a TLP Answers please! Use a Search Engine.... deduct two points! His Honorific Holeyness asks you to send your entry (plus a suitably large donation for His Eminence’s Home for Wayward Blondes to: Prof. Shatterini c/- BINTEL, 55 York Street, Sydney 2000 or by email to: info@bintel.com.au James Hardie shares, pollie promises and other questionable sources of filthy lucre are discouraged in favour of Euros, US dollars or platinum bars. Mars Bars would be nice too. Remember, deduct points for Googling or for Yahooing. Night Sky is published monthly by The Binocular and Telescope Shop Pty Ltd 55 York Street, Sydney NSW 2000. Tel: (02) 9262 1344 Fax: (02) 9262 1884 Mike Smith Editor. Contributions are welcome. Printed by Omega Creative Communications 4 Campbell Street, Artarmon NSW 2064. This newsletter is available at The Binocular and Telescope Shop and at many astronomical society meetings and astronomy centres around Australia. Night Sky is delivered monthly to any address in Australia for $12.00 per year.