June 2012 * Volume 324

Published monthly since 1985 byThe Binocular and Telescope Shop

84 Wentworth Park Road, Glebe NSW 2037and 519 Burke Road, Camberwell Vic 3124

Oscillations in the day ...................2Spotty Leopards ? ..................2 June sky ........................................3Mick ‘n Don ........................... .......4

subscribe to NIGHT SKYReceive your copy every month free by email. Get an eyeful of sky news in the mail or on your computer. email: mike@bintel.com.au and ask for your copy!

It’s amazing that with all the proper information available via TV, radio and the internet peo-ple can still get it wildly wrong. No, you can’t wear solar glasses and look safely through binocu-lars or a telescope. You’ll cook the glasses, possibly the tel-escope’s eyepiece and probably your eye. Please don’t do it!Solar glasses on their own are quite safe. I suspect that many people, whose eyesight isn’t the best may struggle to see the tiny disc of Venus as it passes across the face of the Sun. The weather will also have a lot of say on the day! At the moment the weather gods believe that not enough virgins have been sacrificed. More work must be done.

So far the crazies haven’t been waffling on too much about the transit of Venus. The his-torical side of it is, I think, the most interesting and, as far as Australians are concerned, the most important. James Cook did find and map both islands of New Zealand as well as the east coast of Australia. Much as we respect his brilliance as a navi-gator we can pause for reflec-tion on the undoubted abilities of the polynesians who preced-ed him by five hundred years is less advanced sailing boats.

We hear strange rumours of bitter intercenine struggles in a well-known astronomical society somewhere along the east coast. Looks as if some members are unhappy with the people running affairs... but don’t want to take over the reins themselves... looks like too much work is involved. Sounds just like politics, dunnit?

We’ve been asked if anybody runs classes for beginner as-trophotographers. Does any club... or individual... run such a course? Please let me know.

So many people carried on about the NIGHT SKY not be-ing available in print from this month that we had a long hard think about it and made the decision to con-tinue printing each month. So... if you prefer the printed version slip me $20 and you’ll get it each month for a the next year. Okay?

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www.binte l .com.au

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AMATEUR ASTRONOMERSJOHN DOBSON

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WHO HAVE MADE A DIFFERENCE

John Dobson was born in Beijing on September 14th 1915. His father was teaching zoology at Beijing Univer-sity, which had been founded by his grandfather. When he was twelve years old the Dobson family moved to the United States and settled in San Francisco,.John completed his high school edu-cation in 1933 and enrolled at the University of California in Berkeley. He eventually gained a degree in 1943 in chemistry and mathematics and began working at Caltech and then at the Berkeley Radiation Laboratory.Shortly afterwards he entered a Ve-danta monastery, part of the Ramak-rishna religion, where he studied to understand the workings of the uni-verse around him. Deciding that to see the universe better he’d need a telescope, he constructed a scope with old lenses he found..This whetted his appetite. He used the information found in the book ‘Mak-ing Your Own Telescope’ to turn a twelve inch porthole glass into a re-flecting telescope. His first glimpse of the Moon through this large but simple telescope sealed his fate. Dob-son knew that he’d dedicate his life to sharing his telescopes with the public. Dobson began making telescopes for others, with whatever materials came inexpensively to hand.

The result was that many people be-gan building their own telescope un-der his guidance. Years later he pro-duced a book that explained how and why a dobsonian should be made.Dobson joined forces with local ama-teur astronomers in the late 1960’s to form an astronomy club that met only on street corners with their tele-scopes, their purpose was to show the skies to passersby and local residents. The name was obvious and thus The San Francisco Sidewalk Astronomers was born. Larger and larger telescopes were built. They became so large that, to move them around the members bought ventually the club acquired an old school bus that was painted up and became known as Starship Cen-taurus A. It allowed members and their telescopes to travel the country, pausing in national parks to show the wonders of the sky to holiday-makers and visitors. For many years it was the club’s bedroom and telescope storage shed. Others have taken its place over the years.In nineteen sixty-nine the Sidewalk Astronomers were invited to the Riv-erside Telescope Makers’ Convention held in southern California. The 24-inch Dobsonian telescope brought by the Sidewalk Astronomers was a complete surprise to most amateurs at the meeting. They were used to seeing much smaller telescopes mounted on conventional equatorial mounts.Rather bravely, the organizers award-ed John first prize for the optics and second prize for mechanical excel-lence, despite the telecope being very simple. Amateurs around America sat up and noticed! Dobson’s ideas of a simple telescope on a simple, inex-pensive base were looked on by many with suspicion. How could a telescope be made so simply, so cheaply and perform so well?Once the design became known and the principles of cardboard tubes and teflon-on-formica bearing surfaces was understood the idea spread like wildfire around the USA and then overseas. In Australia there were few ‘Dobsonian’ telescopes as they were called until a visit was arranged by members of the Astronomical Society of Victoria in the late 1980’s. Dobson also visited Sydney. cont Page 4

He began to sneak out of the monas-tery at night and drag his telescope to suburban streets where he’d set it up and invite passers-by to enjoy views of the universe with him. He even loaned his telescope to youngsters who showed particular enthusiasm for astronomy.Over the months he polished mirrors and assembled over a dozen telescopes for others. This activity eventually got to the ears of the monastery’s abbott who warned him to cease and desist... or face expulsion. The decision was eventually made for him and Dobson found himself on the street.He slept on friends’ couches, above garages and in cellars. On clear nights he’d take his telescope, which he’d named ‘Stellatrope’ to the corner of Jackson and Broderick Streets in Pa-cific Heights, a couple of kilometres from the Golden Gate Bridge.There, he’d invite anybody who would listen, to “see the stars, see the Moon”Dobson continues to live, to this day a very spartan vegetarian lifestyle, relying on friends and followers for subsistence. He’s never made a liv-ing from the telescope that bears his name. He soon began to give lectures and demonstrations on telescope mak-ing; this developed into a full series of lessons on telescope building.

OBSERVING THE

TRANSITa warningWe’ve heard that some

people think it will be safe to use solar glasses to look

through binoculars or telescopes at the transit.

IT IS NOT SAFE TO DO THAT !

IT IS VERY DANGEROUS TO DO THAT.

Solar glasses are safe to look at the Sun.

Telescopes need a proper solar filter at the front of the

telescope.The two do not work

together.Don’t do it !

If in doubt ask us. 02 9518 7255

Years ago telescopes used to be sold with a small green

Moon filter and a small black Sun filter.

They were meant to be screwed into the back of an

eyepiece.The Moon filter is safe for

observing the Moon.The Sun filter was very

DANGEROUS and had a tendency to crack under the

intense heat of the Sun.Don’t use such an eyepiece

filter. Throw it out!

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John Dobson has a rare quiet moment in Sydney during a visit.

COMING SOONfrom

Tele VueDelos 3.5mm 4.5mm,8mm, 12mm, 14mm

to join the 6mm 10mm and 17.3mm

sweet !

The Binocular and Telescope Shop, 84 Wentworth Park Road, Glebe NSW 2037. Tel: 02 9518 7255The Binocular and Telescope Shop, 519 Burke Road, Camberwell Vic 3124. Tel: 03 9822 0033 June 2012 * Volume 324 * Page 2

CAN THE LEOPARD CHANGE HIS SPOTS?Mel watches the eternal struggle between the hunter and the wolf

After what’s called ‘mature consideration’ (otherwise known as I got shouted down in an argument) a decision has been made to continue production of the printed edi-tion of NIGHT SKY. It had been our intention to cease printing this newsletter with this edition and rely on the email edition.Comments from many readers- and a plea from a couple of astronomy societies has induced us change the decision. So, if you would like to receive the printed version of NIGHT SKY each month please forward $20 for a year’s subscrip-tion to this august monthly newsletter that has been in pro-duction since 1985. Mike Smith

One of the most forgotten constellations in the sky at this time of year is Lupus. In mythology, In Greek and Roman mythol-ogy Lupus was a beast impaled on the Cen-taur’s (Centaurus) spear and offered as a sac-rifice to the gods on their alter – the nearby constellation of Ara. However, it appears that Lupus wasn’t associated with the wolf until Renaissance times. Arabic countries saw Lupus as either a lioness or spotted leopard.Lupus is easy to find, located between Scorpius and Cen-taurus, which perhaps explains why it is so often over-looked. However, Lupus does have some fascinating sights, in particular numerous double stars.

Gamma (γ) Lup is a blue-white star of magnitude 2.8. It has a close com-panion with an orbital period of 190 years. This binary can be split with telescopes of aperture 200mm or above. γ Lup is about 570 light years away.Epsilon (ε) Lup is a blue-white star with a magnitude of 3.4. It has a companion star of magnitude 8.8, putting it well in the reach of small aperture telescopes. However there’s also something here for large aper-ture telescopes, with the main star a close double. ε Lup lies about 504 light years away.Eta (η) Lup is a double star consist-ing of a primary blue-white star with a magnitude of 3.4 and a companion of magnitude 7.9. The pair are about 493 light years away. However, the compan-ion can be hard to see in small aperture telescopes but is certainly worth a try. Kappa (κ) Lup is an easy visual double for small aperture telescopes. Both stars are pale yellow and have magnitudes of 3.9 and 5.7. There has been no real change to the system for more than a century so they are a physical binary in a wide orbit. They are about 188 light years distant.Mu (μ) Lup is a multiple star system. Small aperture tele-scopes see a main blue-white star of magnitude 4.3 with a wide companion of magnitude 6.9.

Telescopes with apertures of 100mm, using high magnifica-tion may be able to split the main star into a double, with both stars having nearly identical magnitudes of 5.0 and 5.1. The system lies about 291 light years away.Xi (ξ) Lup is a pair of blue-white stars with magnitudes of 5.1 and 5.6. They are about 200 light years away and are an excellent target for small aperture telescopes.Pi (π) Lup appears as one blue-white star with magnitude

3.9 to the unaided eye, lying about 500 light years away. However a telescope with an aperture above 75mm will show two close blue-white stars of almost identical mag-nitudes of 4.6 and 4.7.NGC 5986 is a globular cluster with a magnitude of 8. In small aperture telescopes it appears as a smudge, with medium to large aperture tele-scopes revealing the stars that make up this cluster. It is about 33,000 light years away.NGC 5822 is an open cluster lying about 2,400 light years away. It is a large, loose cluster that is visible in both binoculars and small aperture telescopes and contains about 150 stars. Given the fact that it is a large

cluster, binoculars are probably the best way to view this gem.NGC 5824 is a 9th magnitude globular cluster and is very condensed and symmetrical in appearance. This object is easy to observe in telescopes with apertures of 75mm or greater. NGC 5824 is approximately 107,000 light years away.

Although the cold of winter can be a tough time for observ-ers, there are numerous overlooked sights to be marveled at, making it worth your while to brave those winter chills! Mel

The H-alpha sun often hosts dark snake-like features called filaments. They come in two distinct kinds: active region filaments and quiet region filaments. By far the biggest and darkest are those that occur in the “quiet latitudes” where there are (usually) no sunspots.In sunspot latitudes, and usually close to or intertwined with sunspot groups are the thinner, shorter active region filaments. Harold Zirin in the 1980’s intro-duced three-letter tags for most H-alpha features that is still in use; the filament in spot groups are ARF (active region filaments). These latter filaments are the ones most involved in flaring. ARF lead short lives as they erupt during flares – but quickly reform along the inversion line (or channel) between spots of opposite polarity in a group. Aside from flaring the ARF channel often hosts surges too, it seems.ARF do not have to occur in spot groups; Zirin notes their persistence at sites of older spot groups where spots are gone. Such ARF can cause strong “spotless” flares, several have been logged during SC24.The May 1, 2012 logs, amongst other things, showed a very bright prominence at the sun’s NE limb. First noted at 21:21 (Fig, a) it showed a low filament/prominence 10Mm high with extensions to the N and S, making a total length of 70Mm. Its brightness matched the chromosphere – indicating “activated” conditions, “that is, internal motions increase” (Schrijver and Zwaan , p198). Despite this it seemed stable, and I turned to examine other regions. No sign of motion in the ARF was noted though it grew slowly higher due to solar rotation. The ARF was sited at +13, 223, placing it in the zone of current northern spots, though no signs of nearby spots was noted. A typical quiet filament is only 10 percent disc brightness, but this was ten times brighter, and equalled the disc.By 22:45 (84min. later) it had abruptly detached from the limb (Fig, b), except for two thin footpoints. Its lower parts were still bright but upper parts were now ~50 percent disc brightness.

The rapid growth in area of the prominence (Fig, views c and d) is typical of plasma once confining fields have released their grip – it rises and grows larger. Lower parts remained dense and bright while upper parts faded away into the background. View d shows the northern parts fully detached while one foot-point endures at the south end.By 23:05 much of the original matter has faded but denser strands persist – while the final footpoint has let go. However filament material is now draining, it seems, via other points on the disc to the N and S, ~110Mm apart. Now the persistent southern half of the filament begins to rise in a slender brilliant arch (Fig, e, lhs). Yet this was not to be: faint material at the north end, that seemed to have most-ly drained to the surface, now felt the (magnetic) urge to rise in an even higher arch (23:13,Fig,f, rhs). This northern arch quickly reached ~30Mm, while south-ern parts collapsed back to the surface (though still bright) like a surge retract-ing. By 23:16 the faint arch had reached ~35Mm while the south component was back to a low 10Mm above the limb (Fig, g).When these logs are viewed in rapid succession an oscillating motion is seen, with first the left side rising, and then falling as the right side takes its turn to fall, then rise. In Big Bear Lake, California, Zirin (1970’s) used old Disney Corp “Stop-motion” cameras to log movement in erupting prominences/fila-ments – but the writer uses pencil, paper and stopwatch – while wishing for a ‘turn’ on BBSO’s famous vacuum refractor.

HARRY DOES THE OSCILLATION TANGO !

the NIGHT SKY

The bid to host the world’s largest radio telescope has ended in a tie, with the project to span South Africa, Australia and New Zealand. The announcement was made at about 8.40pm (WST) by the SKA Organisation’s board, which had gathered in The Netherlands.“We have decided on a dual site approach,” said SKA board chairman John Womersley at a press conference held in Hol-land. South Africa’s site for the project is the Karoo region in the Northern Cape, while the joint site spreads from the Mur-chison Shire in Western Australia’s Mid-West region to the top of New Zealand’s South Island.The Square Kilometre Array, or SKA, will be the largest and most capable radio telescope ever made and will allow scien-tists to see back in time. The $2 billion project comprising 3000 dishes will be funded by a consortium of 20 nations and seeks to answer the biggest questions about the early universe.

With a discovery potential 10,000 times greater than the best present-day instruments, it will observe such things as what happened after the big bang and how galaxies evolved, and will attempt to uncover more about the “dark energy” that fills the majority of the universe. The telescope array, which is expected to have a working life of several decades, could even detect signals that may be from extraterrestrials.According to Scientific American magazine, the South African bid was at one stage viewed as narrowly superior to the joint proposal because the site was at a higher altitude and construction costs were lower but the Australia/New Zealand bid offered cheaper insurance costs and less likelihood of the site being encroached on by future development.Both sites were shortlisted because they were regions of minimal radio interference.Peter Quinn, director of the Perth-based Institutional Centre for Radioastronomy Research, said he was happy with the decision, which made a lot of scientific and commercial sense. It would take advantage of the best of both sites and build on the investments that had already been made by the bidders, Professor Quinn said. “It’s not just window dressing - this is a real, sensible solution,”. He said phase one of the project would run until about 2020 and would involve construction of 10 per cent of the array, with the remainder to be built in phase two.Both sides would have their turn with either low frequency aperture arrays or high frequency dishes, but WA would ini-tially experiment with the first elements of middle frequency technology during phase one.

THE SQUARE KILOMETRE ARRAY

The Binocular and Telescope Shop, 84 Wentworth Park Road, Glebe NSW 2037. Tel: 02 9518 7255 The Binocular and Telescope Shop, 519 Burke Road, Camberwell Vic 3124. Tel: 03 9822 0033

Saturn is very high in the northern sky at mid-evening. This is an

excellent chance to observe the ringed planet and its moons. Git outside with a telescope!

Neptune: Is in Aquarius rising before midnight and promptly goes into retrograde motion. Ask

for an explanation of that!

Uranus: is doing a Jonah this month. It’s in Cetus, and looks like a greenish

‘star’ after midnight in the East.

3rd Moon at Perigee

4th Full Moon

11th Last Quarter

16th Moon at Apogee

20th New Moon

27th First Quarter.

Pluto: Has looked carefully at the videos of the monastery leader.

Amazed at his ability to leap out of the box and sprint for the door. Timing a bit off, but definite chance of winning a race one day if he’s not nobbled by his friends.

Omega Centauri is a globular clus-ter. It’s bright and big. ω Centauri is different enough to other globular clusters that some think it may be a pygmy galaxy. It is located about 15,800 light-years from Earth and the stars in its center are so crowded that they are estimated to average only 0.1 light years away from each other. It is one of the few globular clusters visible to the naked eye and appears about as large as the full Moon.

June 2012 * Volume 324 * Page 3

You can shop on-line at www.bintel.com.au for your astronomical needs.

Mercury: is visible low in the western evening sky. It moves steadily from Taurus to Cancer

during the month.

Mars is high in the north-western sky above

Regulus in Leo. Mars will now slowly lose brightness as it slides towards the western horizon.

Venus: is in inferior conjunction. On the 6th it passes across the face

of the Sun. If you miss this one you’ll have to wait till December 2117 for

another chance.

Jupiter is rising before just dawn in the East. It’s sitting to the right of the

Pleiades star cluster and above much brighter Venus..

Evening sky June 2012

Alan Shepard wanted to be the first person to play golf on the Moon. He took three golf balls and the head of a six iron, which he attached to the bottom of a sampling instrument and told Mission Control to watch. Shepa-rd buried the ball on the first swing. His second swing knocked the ball a few feet before it came to a dead stop. His last shot was more succesful, and the ball disappeared in a graceful arc in the direction of a crater over a ki-lometre away!

Mars

Saturn

The transit of Venus will be visible on Wednesday 6th from 8.15am in the morning till 2.44pm in the afternoon along the east coast. Mid transit at about 11.30am.Don’t try to observe it without proper solar glasses or a proper solar filter.You could easily damage your eyes and your telescope. If in doubt... ask!http://www.transitofvenus.com.au/

Solstice is on the 21st

The Binocular and Telescope Shop, 84 Wentworth Park Road, Glebe NSW 2037. Tel: 02 9518 7255 The Binocular and Telescope Shop, 519 Burke Road, Camberwell Vic 3124. Tel: 03 9822 0033

His Eminence Professor Dr Nervo Shatterini, Director of the Member for Members asks that you cast aside any doubts, sign the empty docket below and answer the fol-lowing questions put by 60-Today-7.30 et al.:

June 2012 * Volume 324 * Page 4

June

Macarthur Astronomical Society Inc: NSW ☎ 0402 479 776 Trevor Rhoades www.macastro.org.auSutherland Astronomical Society Inc: NSW☎ (02)9832 4082 Brett McMillan.www.sasi.net.auNorthern Sydney Astronomical Society Inc: ☎ Bob Fuller 0423 971374 www.nsas.org.auSydney City Skywatchers (BAA) (NSW) ☎ 9398 9705 www.sydneycityskywatchers.asn.auThe Astronomical Society of NSW. ☎ 0428 965 249 John O’Brien www.asnsw.comThe Western Sydney Amateur Astro Group Inc ☎ Gerry Aarts 0416 292 020 www.wsaag.org.auwww4.tpgi.com.au/users/wsaag Sydney Northwest Astronomical Society☎ (02) 9634 1736 Ken Petersen The Hawkesbury Astronomical Association: ☎ (02) 4572 1568 Adrian Saw .The Wollongong Astronomy Club. NSW☎ (02) 4261 9369 Paul BrownThe Illawarra Astronomical Society: NSW ☎ (02) 4276 3199 Peter McKinnonwww.illawarraastronomicalsociety.hostoi.com Shoalhaven Astronomers: South Coast NSW ☎ (02) 4423 2255 Jack Apfelbaumwww.shoalhavenastronomers.asn.auThe Astronomical Society of the Hunter: NSW (02) 4937 4664 Col Maybury colmay@kooee.com.auNewcastle Astronomical Society: NSW ☎ (02) 4950 0725 Allan Meehan www.nas.org.auCoffs Harbour Astronomical Society: NSW ☎ (02) 6653 2742 Win Howard Coonabarabran Astronomical Society, NSW☎ secretary@coona-astro.org.au Central West Astronomical Society, NSWJohn Sarkissian: john.sarkissian@csiro.au. Port Macquarie Astronomical Association NSW☎ (02) 6582 2397 Joy Woods www.pmobs.org.auGrafton Astronomical Society, NSW☎ (02) 6643 1349 Mick Austin, President Pro tem.Bombala Astronomy Group, NSWUniversity of New England Astronomical Society ☎ (0427 892 011 Chris Wyatt Clarence Valley Astronomical Society☎ (02) 6643 3288 Steve FletcherBallaarat Astronomical Society: Vic ☎ (03) 5332 7526 bas@cbl.com.au http://observatory.ballarat.netBendigo District Astronomical SocietyPO Box 164 Bendigo Vic 3552 . Kate McMillanAstronomical Society of Victoria Inc ☎ (03) 9888 7130. Linda Mockridge www.asv.org.au Latrobe Valley Astronomical Society Vic☎ (03) 5122 3014 home.vicnet.net.au/~lvas Astronomical Society of Geelong, Vic☎ 0407 345 070 Frank Baker for details.http://vicnet.net.au~asogMornington Peninsula Astronomical Society, ☎ 0419 253 252 Peter Skilton for details. Astronomy Benalla 03 5762 1523 Rupe Cheethamwww.astronomybenalla.org.auAstronomical Society of Albury-Wodongawww.asaw.org.au Mount Burnett Astronomical Society☎ 0409 703 929. mtburnettobservatory.org ☎Petra De Ruyter 0431 535 417Snake Valley Astronomical Association (Vic)☎ 0418 425 207 Me Ken James.Canberra Astronomical Society: ACT☎ (02)6248 0552 J. Howard www.mso.anu.edu.au/casBrisbane Astronomical Society: Qld ☎ (07) 3321 8511 Darryl Mitchellwww.bas.asn.auSouthern Astronomical Society:Qld☎ 0421 866 376 Joe Zerafa.www.sas.org.auAstronomical Association of Queensland, Qld☎ Peter Hall (07) 3378 1173 www.aaq.org.auSouth East Queensland Astronomical Society, ☎ (07) 3239 0032. www.seqas.orgIngham Amateur Astronomers Club☎ (07) 4776 5773 Tracey Castles.Bundaberg Astronomical Soc. Qld☎ (07) 4159 7232 www.interwox.com.auRedlands Astronomical Society Qld☎ (07) 3207 2818 Chris Tacke www.ras.org.auBundy Skywatchers (South-Central Qld)☎ (07) 4159 9674 Karlene GalwayAstronomical Society of South Australia, SA ☎ (08) 8338 1231 Tony Beresford. www.assa.org.auAstronomical Society of Tasmania, Tas ☎ 0419 305 722 Bob Coghlan. www.ast.n3.netAstronomical Society of Alice Springs N.T. ☎ (08) 8952 9817 Annette GreenDarwin Astronomy Group NT☎ (0420 238 663 Matt Bartonwww.darwinastronomy.comGove Amateur Astronomers, NT ☎ 0417 601 490 Ian Maclean for information.Astronomical Society of Western Australia, WAhttp://www.aswa.info ☎ (08) 9364 9603Astronomical Society of The South-West, W.A. ☎ (08) 9721 1586 Phil Smith.

Night Sky has been published monthly since before some of you were even born by

The Binocular and Telescope Shop Pty Ltd84 Wentworth Park Rd, Glebe 2037

Tel: (02) 9518 7255 Fax: (02) 9518 5711Any errors, mis-spellings, dropped apostrophes and missing words are the fault of Mike Smith.

Complain at - mike@bintel.com.auPrinted by the really nice people at 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 available free by email.

Ask mike@bintel.com.au to be on the mailing list for the NIGHT SKY.

Hey Don,I hear they had to do a

King Solomon decision on the Square Kilometre

Array telescope.

A what?.

Well, they had to decide whether to set it up in Africa or Australia.

So that nobody’s feelings would be hurt

they’re setting up half here and half in

South Africa... oh, and a bit of it in

New Zealand.

Ah, even King S o l o m o n ’ s scratching his head over that one.

Why a bit in New Zealand?

HEADS UP FOR STAR PARTIES!

Star Parties! Where amateur astronomers get to meet old friends, look at the skies, learn, listen to talks and see the latest equipment in use.Central West Astrofest (Parkes) 14-15 JulyQueensland Astrofest (Duckadang) 10-19 AugustBorder Stargaze (Albury Wodonga) 15-19 AugustVic South Desert Spring Star Party 12-14 October.All are listed on the ‘net!

Mt. BURNETTOBSERVATORY

(1) It’s above Indus, beside Sagit-tarius, it is....(2) Where is the Ghost of Jupiter?(3 Where do you find black holes?(4) Which star was called the Demon Star?(5) The Magnetic Compass in the sky?(6) When were radio waves from space identified?(7) Which famous supernova could be seen in daylight for 23 days?(8) How fast is the interstella wind blowing?(9) Does the Moon ever travel through Orion?(10) What’s the brightest star in Ca-nis Major?(11) What’s the surface gravity of the Moon?(12) How many astronomers does it take to change a lightbulb?(13) Which planet was discovered in Aquarius in 1846?(14) Which are the brightest and dimmest constellations?(15) Which constellation was called Erichthonius by the Greeks?(16) What is ‘perigalacticon’?(17) How many Messier objects are in Centaurus?(18) What was the name of the band that accompanied Dig Richards?(19) Who named the Jewel Box clus-ter (NGC4755)?(20) In which constellation is the star Aldebaran?

The answers to these questions, and many other things may be found by quietly turning this page upside down and reading. No correspon-dence not containing money will be entered into.

(1) Microscopium(2) It’s a planetary nebula in Hydra.(3) In black socks.(4) Algol in Perseus.(5) Pyxis(6) December 1932 by Karl Jansky.(7) The Crab Nebula in AD1054(8) About twenty kilometres per second.(9) Yep.(10) Sirius, the brightest star in the sky.(11) 0.165 compared to Earth at 1.0.(12) Two. One to change it, the other to complain about light pollution.(13) Neptune.(14) Crux and Vulpecula.(15) Auriga(16) The point when a star is closest to the galactic centre.(17) None.(18) The R-Jays(19) John Herschel.(20) It’s in Taurus, on the horn.

The observatory was originally built in 1972 and was used by students at Monash University until recently.Monash University made the decision to close the obser-vatory last year because there was little use for the ageing telescope so far from their campus.A group of people keen to keep the observatory open, including James Murray, Ray Schmidt, Perry Vlahos, Barry Cleland and Ken Beard began a campaign to save the observatory, and give it a new life as a community resource.The observatory is in a great spot - well above sea level - and away from the city lights.It is hoped the observatory will be able to be used by schoolchildren.The observatory is at 430 Paternoster Rd, Mt Burnett, Vic. For more information on the observatory, visit mt-burnettobservatory.org or phone 0409 703 929.Below: Mt Burnett Observatory Inc. member Perry Vla-hos with the telescope in the astronomical observatory at Mount Burnett, near Cockatoo, Victoria.

MACQUARIEUNIVERSITY

MACQUARIE UNIVERSITY The Department of Physics and Astronomy at Macquarie University invites you to capture a glimpse of the Transit of Venus. This will be the last transit before the next one in December 2117. The planet Venus will pass in front of the Sun, just as it did when Captain James Cook observed it from Tahiti in 1769. Cook’s observations helped to measure the distance to the Sun and provided the key scientific rea-son for his voyage. Macquarie University expert astronomers will project a live image of the Sun onto a white screen, set up telescopes for people to view details on the surface of the Sun and will be on hand to answer any questions.FRIDAY NIGHT PLANETARIUM SESSIONSFriday night planetarium shows are now being run at Mac-quarie University from 6:00-7:00 pm for up to 40 people (chairs provided). Tickets for these events must be booked online. Friday night sessions are held in the E7B Courtyard on the Macquarie University campus, rain or shine. The courtyard is the large carpeted area indoors the middle of the building (indoors).

In Sydney he spoke to a large and enthusiastic crowd. Telescopes bearing his ‘imprimatur’ began popping up everywhere and eventually some of the major manufac-turers began marketing Dobsonian telescopes.John Dobson has visited many parts of the world to ‘spread the word’. The success of his mission to bring large, simple telescopes to the public is his legacy. Tha man himself, whilst mindful of his place in amateur as-tronomy, has decried the use of the term ‘dobsonian’. He prefers to call such creations ‘sidewalk telescopes’. Even John Donson was surprised at the numbers of large and then very large telescopes that would turn up at star par-ties. caught on, it was Dobson himself who did the under-estimating. At many star parties these days the Dobson-type telescope is very common.

JOHN DOBSONcontinued from Page 1

A sidewalk telescope, as Dobson calls his creation, should be simple in construction with ‘Sonotube’ card-board as the main barrel, plywood or MDF for the base and teflon and laminex as the bearing surfaces.. These days very large Dobsonians may be constructed with take-apart tubes of carbonfibre and a Seurrier truss sys-tem as seen in observatory-sized telescopes. These are very transportable in fmily-size vehicles.In 2008, at the age of 93 John suffered a slight stroke. This has restricted his travelling, but despite his advanced years and his infirmity he’s still the same wily, amusing, talkative, argumentative, engaging, inspiring astronomer he always was. Those of us who’ve met the man know we’ve been in the presence of a ‘one-off, an original’, and we’re the better for it. MS

John Dobson on his second visit to Sydney with Don Whiteman with a Dobsonian telescope.