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09 Night Sky September.Indd Published monthly since 1985 by The Binocular and Telescope Shop 84 Wentworth Park Road, Glebe NSW 2037 and 519 Burke Road, Camberwell Vic 3124 www.bintel.com.au September 2011 * Volume 315 OUR NEW WEBSITE IS UP new style, more information, easier to use. Spring Equinox occurs on the 23rd of September. Watch the www.bintel.com.au Sun come up directly East and set directly in the West. The day The Binocular and Telescope Shop website has been revamped and upgraded to give our customers a better and more satisfying shopping experience. Better and the night are just about equal. laid out, more intuitive and easier to use. There’s much more information available to assist both beginners and experienced amateur astronomers.... as well What would we have if we didn’t as birdwatchers, whale-watchers, wildlife observers and everybody who wants to be able to use either binoculars or a telescope. Naturally, after such a mam- have seasons? A mess is what moth task in upgrading, there are likely to be a few glitches. Bear with us while we sort them! We hope you like the new Bintel experience. Mike Smith we’d have! And we’d probably not be here to see it. Discuss * * * STUDENT MEASURES UNIVERSE - IT’S GETTING BIGGER, HE SAYS With the constant launching of THE HUBBLE CONSTANT IS ACCURATE SAYS NEW WORK. spacecraft by the Americans, One of the most accurate measurements ever made of how fast the universe is expanding has been made by a PhD Russians, Chinese and even the student at the University of Western Australia. Florian Beutler, a PhD candidate with The International Centre for Ra- Japanese we are in for a bonanza dio Astronomy Research (ICRAR) at the university, made the calculation by re-measuring the Hubble constant. (The of scientific information over the Hubble constant is a key number in astronomy used to calculate the size and age of the universe). next few years. The latest Ameri- He said that as the universe swelled, it carried other galaxies away from ours and the Hubble constant linked how fast can launch is Juno, headed for galaxies were moving with how far they were from us. Jupiter. It will take a while to get By analysing light coming from a distant galaxy, the speed and direction of that galaxy can be easily measured. Mr there, but once in orbit around the Beutler used data from a survey of more than 125,000 galaxies carried out with the UK Schmidt Telescope at Siding giant planet, should supply amaz- Spring, NSW. The 6dF Galaxy Survey is the biggest survey of relatively nearby galaxies, covering almost half the sky. ing images and a wealth of scien- Beutler has measured the Hubble constant with an uncertainty of less than five per cent. tific knowledge. Determining the Hubble constant this way is as precise as other methods, and provided an independent verification of those methods. “The new measurement agrees well with previous ones, and provides a strong check on previous work,” said Professor Matthew Colless. Professor Lister Staveley-Smith, ICRAR’s deputy director of science, said large sur- We hear that* one * of the* biggest veys like the one used for Mr Beutler’s work, generated numerous scientific outcomes for astronomers internationally. amateur astronomical societies in Australia is beginning the task of looking for a permanent home... again. They’ve been looking for WATER FLOWING ON MARS’ SURFACE ? many years, on and off. I reckon Comparing the two images shows what looks exactly like creeks flowing in a ‘wet’ season. they should all become members of a bowls club and ..... but that wouldn’t be cricket, would it? * * * Word has it that a planetarium and science centre is in the off- ing in the Central West of NSW. As somebody sagely pointed out there are a hundred schools within 150km of Orange. The Regional Development Authority is being approached to help fund the project. The site, between the Orange Botanical gardens and an adventure playground has been earmarked by the local coun- cil. Such a project really needs to become reality. Let it be ap- proved....please! * * * On the subject of planetaria... why does Sydney not have a full-size planetarium? We really Dark, finger-like features appear and extend downhill on some Martian slopes during late spring through summer, fade and then return during the next spring. Re- should, shouldn’t we? peated observations have tracked the seasonal changes in these recurring features on several steep slopes in the middle latitudes of Mars’ southern hemisphere. Some aspects of the observations still puzzle researchers. Water would either freeze or evaporate, but flows of liquid brine best fit the characteristics of what has been observed. Saltiness lowers the freezing temperature of water. Sites with active flows get warm enough, even in the shallow subsurface, to sustain liquid water A huge amount* of* work * by staff that has about as level of salt as the Earth’s oceans. Pure water would freeze at the known temperatures in these areas of Mars. at Bintel has resulted in the new The features imaged are about 50 centimetres to 5 metres wide and extend several hundred metres downhill. This is much narrower than previously reported gul- website that is now up and run- lies on Martian slopes. However, some of those locations display several hundred individual flows. Also, while gullies are abundant on cold, pole-facing slopes, ning. We had no idea of the these dark flows are on warmer, equator-facing slopes. amount of work that would be The images show that flows lengthen and darken on rocky equator-facing slopes from late spring to early autumn. The seasonal times, latitude distribution and involved. (developers very cun- brightness changes strongly suggest a volatile material is involved, but there is no direct detection of it. These areas are too warm for carbon-dioxide frost and, at ningly never tell some sites, too cold for pure water. This suggests the action of brines, which have lower freezing points. Salt deposits over much of Mars indicate brines were abun- you ahead of time, dant in Mars’ past. These recent observations suggest brines still may form near the surface today in limited times and places. Looks like salty water is there. do they?) I’m grate- ful to Don and Mi- Mel plucks a string or two .............2 subscribe to NIGHT SKY chael in particular Harry talks to the trees ........2 and 4 Receive your copy every month free by email. Get an for their nose-to- Star Map for September ...............3 eyeful of sky news in the mail or on your computer. the-grindstone atti- Mick ‘n Don ....................................4 Details at the bottom of Page 4 tude. Thanks fellas! 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 September 2011 * Volume 315 * Page 2 Harry’s loves M E L PLAYS HER LYRE AND TELLS his groupies. OF OPRPHEUS AND EURYDICE Big Groups - At Last! Spring has sprung Remarkably, the sun, over a hundred and this month we Earth diameters wide, can “change its look at the beautiful spots” very quickly. And this capac- though small con- ity for sudden change is what makes stellation of Lyra. it such an exciting target for daytime Lyra dates from astronomy. The ability is due it seems, ancient times, and to the magnetic nature of sunspots and in Greek mythology their attendant features. represents the lyre In mid July the disc was peppered with (stringed instru- small spots– but one by one they fad- ment) that the infant ed, or rotated out of view – leaving the Hermes invented. disc almost blank on the 25th. Flaring They were (are still) a breathtaking All three groups had strong fields, He gave it to Apollo throughout was weaker than GOES sight in a small ‘scope, a sight we’ve with the preceding spot of 1263 the who then passed it B5. On that day, at the east limb, was not had in over five years –I was re- strongest, at 2600 gauss. Only three on to his son Or- one little spot, dubbed AR11260; and minded of the sun in late 2003 when earlier spots in Cycle 24 had fields pheus, who bravely yet the sun, Readers, was about to “up the biggest groups of C23 were on as strong, so maybe 1263 is setting a travelled into the the action”. parade! trend for stronger sunspot fields Let’s underworld to seek Next day (26th) the single spot had The sketch shows the two biggest hope so – they are needed for C24 his bride Eurydice miraculously morphed into a curved ones on August first: AR1261 was spots to grow big and flare often. So who had been killed chain of eleven spots, spread over 350 area units in size, followed by far this Cycle has been much weaker by a viper. nine degrees of longitude. Then, over 1263 that reached 500 units. The last than its predecessor. The king of the underworld, Hades following days, first one then two big group of this size was seen in late Both of the groups shown developed (Pluto in Roman mythology) liked Delta1 Delta2 (δ1 δ2) Lyrae is a wide groups joined 1260 from around the E 2006. Not shown is 1260, the original the most complex magnetic class, Orpheus’ music and allowed him to double star, consisting of two unre- limb – now three big groups stretched single spot, that grew into a bipolar Beta-Gamma-Delta, which predicts take Eurydice back on one condition, lated stars.
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