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Affiliated Societies are welcome to reproduce any item in this email newsletter or on the RASNZ website http://www.rasnz.org.nz/ in their own newsletters provided an acknowledgement of the source is also included.

Contents

1. Patrick Moore (1923-2012)
2. Stardate North Island Jan. 17-21
3. Stardate South Island Feb. 8-11
4. The Solar System in January
5. RASNZ Conference 2013
6. Long-lost Comet Identified
7. Tau Ceti's Planets
8. Vega's Age and Spin Revised
9. Radioactivity Important for Life?
10. How to Join the RASNZ
11. Gifford-Eiby Lecture Fund
12. Quotes

1. Patrick Moore (1923-2012)

Sir Patrick Moore astronomy populariser, author, TV presenter and Honorary Member of the RASNZ, died on December 9. Many will recall his lecture tour of New Zealand in 1983 and subsequent visit ten years later. Others will remember cutting their astronomical teeth on Patrick's numerous books.

The following are obituaries from two British publications. --------------- From The Times:

Patrick Moore did more than almost anyone else to popularise astronomy in Britain. A television journey in his company across the lunar wastes of through Saturn's rings was a journey of discovery, and his ebullience guaranteed that his performances avoided getting bogged down in technical detail, although he never talked down to his audiences.

His television presence -- and he was a man par excellence of the television age -- was one of donnish dishevelment, with outsize suit, unruly hair, tie gone awry, eyebrows agitated above squinting eyeballs; his words constantly and endearingly, threatening to race ahead of his thoughts. His wild enthusiasm for his subject could be matched on television only by Peter Snow and David Attenborough.

'The Sky at Night', which he fronted without a break from its beginning in 1957, retained a faithful "around midnight" audience. Its presenter was as much the attraction as the latest astronomical discovery; and when, during one of the early live shows, a bluebottle flew into his mouth, he did not hesitate: "I'm proud to say that I swallowed it. Horrifying experience. Buzzed all the way down."

He was old enough to have met Orville Wright and H G Wells, and late in life he wondered whether he had lived long enough also to have met young people who would one day walk on Mars.

He was born Patrick Caldwell-Moore at Pinner, Middlesex. An only child, he was plagued by illness which confined him to bed. At the age of 7 his mother gave him 'The Story of the Solar System', and his future was decided. By the time he was 11 he was a member of the British Astronomical Association and had been presented with his first good telescope.

He was about to go to university when World War II began. In 1940, lying about his age and his health (he had worn a monocle since adolescence), he joined the Royal Air Force. He served with Bomber Command through most of the war, being invalided out in 1945with the rank of flight-lieutenant. He then taught history for five years at Holmewood House Preparatory School near Tunbridge Wells, before illness overcame him.

He was already a member of the Interplanetary Society, and had written papers about the Moon, and in 1948 he translated a French book on Mars. He now took to writing in earnest, and his first effort, 'Guide to the Moon' (1953), straightforward and informative, was a great success.

There followed more guides to the planets and stars, 'The A-Z of Astronomy', 'The planet Venus', 'The Starry Sky' and the ambitious guide 'The Amateur Astronomer'. His most commercially successful work was his 'Atlas of the Universe' (1970, revised 1995), which was widely translated. He published more than 60 books, all typed two-fingers style on a 1908 Woodstock.

In 1957 Moore was suggested to the BBC for a TV programme on flying saucers. His enthusiastic intensity and clarity of exposition made an outstanding impression. On April 26, 1957, at 10.30 pm 'The Sky at Night' was launched.

He was to present it virtually every month from the launch date, a notable exception being July 2004, when he was suffering from a near- fatal bout of food poisoning. He appeared in the 'Guinness Book of Records as the longest-serving television presenter.

He was a well-regarded figure on the international scene and helped to found the International Union of Amateur Astronomers in 1967. He was feted by astronomers in New Zealand, Canada, Russia, Italy and elsewhere, and from 1982to 1984 he was president of the British Astronomical Association.

Sir Patrick Moore, CBE, astronomer, television presenter and author, was born on March 4,1923. He died on December 9, 2012, aged 89.

-- From 'The Times'. Transcribed two-fingers style from 'The Press' of 15 December 2012.

-------------------- From The Economist

In these days of ever more specific expertise, astronomy is one of the few sciences in which the enthusiastic amateur can still hope to make a contribution. Among the most enthusiastic of these self-taught folk was Sir Patrick Moore, the presenter of a BBC astronomy programme called "The Sky at Night", who died on December 9th.

Once a month for 55 years, as regular as the new Moon, Sir Patrick´s monocled face would appear on the nation´s TV screens. He and his guests would tell viewers about a spectacular constellation they might be able to see with their garden telescopes, or discuss results from an interplanetary space probe. It was, for the programme´s fans, exactly the sort of highbrow television that the BBC was created to provide, and which its commercial rivals would never have commissioned. (In fact, "The Sky at Night" was so popular that Mr Moore reportedly turned down offers from other TV stations, remaining loyally with the BBC.)

Despite his determinedly eccentric habits - he was rarely without his trademark monocle, and was a keen xylophone-player - Sir Patrick insisted that it was the beauty of the universe that drew his viewers, rather than any personal magnetism he might have possessed. Nevertheless, to many he was a national treasure on a par with Sir David Attenborough, the indefatigable presenter of the BBC´s big-budget nature documentaries.

Nor was he a dilettante or a lightweight: the study of the Moon was his passion, and he made several contributions to lunar science. Over his half-century on the air, he secured interviews with many notable figures, including Werner von Braun, the ex-Nazi designer of NASA´s Saturn V Moon rockets; Dame Jocelyn Bell Burnell, who discovered pulsars, rotating neutron stars; and Neil Armstrong, a media-shy astronaut. His reputation crossed the Iron Curtain: he was invited to Russia to meet Armstrong´s counterpart, Yuri Gagarin, and became the first Westerner to see results from the Soviet Luna 3 probe, which mapped the Moon´s far side in 1959.

Some of his attitudes struck audiences as odd and even offensive. Sir Patrick disliked Germans and did not care who knew it (his fiancée had been killed in a German bombing raid in the second world war, and he never married). In the 1970s he became president of the short-lived, virulently anti-immigration United Country Party; later he supported the anti-EU United Kingdom Independence Party. He said he had abandoned watching "Star Trek" when a woman occupied the captain´s chair.

These days science is confident and cool. Comedians such as Dara O´Briain and Robin Ince entertain with science-friendly routines. Telegenic stars including Alice Roberts, an anthropologist, and Brian Cox, an astronomer (and ex-member of D:Ream, a 1990s Britpop band), host lavish, popular-science programmes on television. The front-runner to fill Sir Patrick´s shoes is probably Chris Lintott, an Oxford University astronomer, populariser of science and regular guest on the programme. Another candidate might be Brian May, who, in addition to playing the guitar for Queen, a rock band, holds a PhD in astrophysics and is a "Sky at Night" stalwart. Whoever it proves to be, those shoes are big.

2. Stardate North Island Jan. 17-21

When: Thursday January 17 to Monday Jan 21, 2013 Where: Tukituki Youth Camp, Tukituki Valley, near Havelock North, Hawkes Bay

For anyone with an interest in astronomy, StarDate provides opportunities to look through a range of telescopes, listen to a wide range of astronomy related talks and meet a variety of astronomers. See http://www.astronomynz.org.nz/society-meetings/society-meetings.html for details

3. Stardate South Island Feb. 8-11

Stardate South Island will be on the new moon weekend 2013 February 8- 11 at Staveley, near the hills inland from Christchurch. Online registration is at http://www.treesandstars.com/stardate/ along with all the details you need.

Like its North Island counterpart it is great place to meet other amateur astronomers, to learn and, weather permitting, to look through a wide variety of telescopes.

4. The Solar System in January

The Earth is at perihelion on January 2, when the distance between Earth and Sun will be 0.983 AU, just over 147 million km. The Sun´s apparent diameter will be at its greatest, 32.5 arc-minutes.

Phases of the moon (times as shown by guide)

Last quarter: Jan 5 at 4.58 pm NZDT (3:58 UT)

New moon: Jan 12 at 8.44 am NZDT (Jan 11, 19:44 UT)
First quarter: Jan 19 at 12.45 pm NZDT (Jan 18, 23:45 UT)
Full moon: Jan 27 at 5.38 pm NZDT ((4:38 UT).

The planets in january

Jupiter will be the prominent planet of the evening sky, as will be Saturn in the early dawn sky. Venus will appear low to the east shortly before sunrise. Mars, in the evening, will be very low and become lost in twilight during the month. Mercury starts the month in the morning sky but becomes an evening object after superior conjunction. It is likely to be too close to the Sun to see throughout January.

Mars and jupiter in the evening sky.

Mars sets about 90 minutes after the Sun at the beginning of the year. On the 1st it will be only some 6° above the horizon 45 minutes after sunset. At magnitude 1.2 it will not be an easy object in the still bright sky low to the west. It will get steadily lower during the month so lost to view. By the end of January the planet will be setting about 50 minutes later than the Sun.

Jupiter will be a much easier object. It transits late evening at the beginning of January. At this time the star Aldebaran will be just over 5° to the upper right of the planet. The asteroid Vesta at magnitude 6.9 will be a similar distance also to the right of Jupiter and about half the distance low and slightly to the right of Aldebaran.

Jupiter will be moving in a retrograde sense to the west through January but gradually slowing until in the early hours of the 31st it is stationary. By the 31st the planet will transit and be highest just before 9 pm. Jupiter is currently well north of the equator so low in southern skies. The transit altitude is 28° at Wellington.

On January 22 the moon will occult Jupiter, but before it rises in New Zealand. The event is visible at night in central South America. By the time Jupiter rises in NZ in the afternoon, the moon will be 1° beyond the planet, the distance increasing to 3° by the time the sky is dark.

The morning sky: mercury, venus and saturn

Mercury is a morning object for the first part of January. It rises 45 minutes before the Sun on January 1 when it will be 11° to the lower right of Venus, but it will be only 2° up half an hour before sunrise. Observation will thus be very difficult. On subsequent mornings Mercury gets steadily closer to the Sun until it is at superior conjunction on the 18th.

After conjunction Mercury becomes an evening object setting after the Sun. By the end of January it sets only 30 minutes after sunset, so again will be too close to the Sun to observe.

Venus will be a little higher than Mercury in the morning sky and, of course, much easier to see. The planet rises about 80 minutes before the Sun on the 1st and more like 70 minutes earlier by the 31st. Thus it should be fairly easy to see before sunrise, rather low in a direction a little to the south of east.

The thin crescent moon will be some 10° to the upper left of Venus on the morning the 10th. The following morning, as an even finer crescent, it will be only 5° directly below Venus. The strong morning twilight may make the moon difficult to see.

Saturn, in contrast to Mercury and Venus, will be an easy-to-see object before dawn. It rises about 2.30 am NZDT on the 1st and almost 2 hours earlier by the 31st. Saturn will be in Libra moving to the east. An hour before sunrise the planet will be to the left of the double star alpha Lib, the two being less than 5° apart by the end of January.

The crescent moon will be about 5° to the upper left of Saturn on the morning of January 7, and a similar distance to the lower right of alpha Lib the following morning.


Uranus and NEPTUNE remain in the evening sky during January. Uranus is in Pisces and Neptune in Aquarius. By the end of the month Neptune will be lost in the evening twilight.

Uranus will dim slightly from magnitude 5.8 to 5.9. It will set about 1 am on the 1st and 11 pm on the 31st, so will remain quite well placed for viewing during the month.

Neptune also dims slightly from magnitude 7.9 to 8.0. It will set close to midnight on January 1 and about 2 hours earlier at the end of the month, no more than an hour after the Sun. On the 31st Mars will be about 3.5° to the left of Neptune and slightly lower.

Brighter asteroids:

Both (1) Ceres and (4) Vesta fade somewhat during January, Ceres from magnitude 7.1 to 7.8, Vesta, slightly brighter from 6.9 to 7.5. Both are in Taurus with Jupiter.

Vesta will be a little over 2° from Aldebaran on January 10 and about 3° from the star on the 31st, when it will be 4° from Jupiter. Ceres will more like 15° from Jupiter and Aldebaran but 2 to 3° from beta Tau, El Nath mag 1.7.

Both Vesta and Ceres are moving in a retrograde sense in January, although Vesta is stationary on the 27th. Ceres has to wait until early February to regain its easterly movement.

(9) Metis is at opposition on January 1 at magnitude 8.5. By the end of the month its brightness will have dropped back to 9.3. The asteroid starts January in Gemini passing within 5´ of the magnitude 5.4 star 28 Gem on the 7th. Metis moves westwards into Auriga on January 12. With a declination +29°, Metis will be low in NZ skies.

More details and charts for these minor planets can be found on the RASNZ web site. Follow the link to asteroids 2012.

-- Brian Loader

5. RASNZ Conference 2013

I would like to remind readers that the 2013 RASNZ conference will be held at the Ascot Park Hotel, Invercargill. It is being hosted by the Southland Astronomical Society. The dates of the conference are Friday 24 May to Sunday 26 May. Members of the RASNZ will have recently received a registration form and a brochure containing details of the conference and local accommodation with their copy of Southern Stars. Brochures and registration forms have also been sent to affiliated societies. Ask your society secretary if you require one.

The registration form and brochure are also available on the RASNZ web site: follow the links on <http://www.rasnz.org.nz>. The wiki registration form provides the opportunity to register on line.

The conference will be followed by TTSO7 (the 7th Trans-Tasman Symposium on Occultations). It will run over two days, Monday and Tuesday, 27 and 28 May. Occultation symposia are held annually, alternating between NZ and Australia where they are held in conjunction with NACAA meetings. Registration for TTSO7 is included on the conference registration forms. More details of TTSO7 are likely to appear soon on the Occultation Section web site, <http://www.occultations.org.nz>

Guest speakers for the conference are still being arranged. Final details are likely to become available in the New Year. One speaker the LOC has already been promised is a mission controller from the European Space Agency, ESA. Also Margaret Austin has agreed to be the after-dinner speaker. We can expect an extremely interesting talk with her involvement in the establishment of the Dark Sky Reserve in the Mackenzie Basin.

The Fellows' speaker for 2013 will be Bob Evans. Bob is the secretary/treasurer of the host society, the Southland Astronomical Society, as well as the editor of Southern Stars and the chairman of the Local Organising Committee for the conference. Not to mention involvement in a number of other local activities in Invercargill and Southland. And still he has time to give a talk! The title of his lecture is: "Reflective and Refractory: Some Observations of New Zealand Amateur Astronomy".

The first offers of papers for the conference have been received, there's still plenty of space for more. The SCC particularly invites papers detailing the astronomical work of individuals, the sections and of astronomical societies. Now is the time to start planning the paper you will present, if you haven´t already done so. Submission forms to present a paper are also available on the RASNZ web site.

The 2013 RASNZ conference will coincide with the Bluff Oyster Festival. As a result there is likely to be a heavy demand for accommodation in Invercargill, so early booking of accommodation is encouraged. See the brochure for details of some options reasonably close to the venue and at the venue itself.

We look forward to seeing many of you at the conference. The Southland Society has the reputation of organising an excellent meeting. The 2013 conference looks set to be just as good as previous ones at Invercargill. Meanwhile the conference organisers would like to extend our best wishes to all for Christmas and New Year.

-- Brian Loader, Chair, RASNZ SCC.

6. Long-lost Comet Identified

In 1932 Clyde Tombaugh of Lowell Observatory -- the discoverer of Pluto -- found a comet on photos he had taken on three nights in January 1931. It was 12th magnitude and diffuse with a strong condensation. Its tail was at least 2 minutes of arc long and pointed west. The comet was, of course, well and truly lost when noticed a year later.

On November 27 and 28 of this year M. Schwartz, P. R. Holvorcem using a CCD on a 41-cm f/3.75 astrograph at Tenagra II Observatory near Nogales, Arizona, discovered an 18th magnitude asteroid in Gemini near Castor and Pollux. It was designated 2012 WX_32. Further inspection of their images and those of other observers revealed that the asteroid was slightly fuzzy and had a short tail. Continued follow-up showed that it was a periodic comet that orbited the sun in 9 years. So it was re-designated P/2012 WX_32 and named Tenagra.

Syuichi Nakano, Sumoto, Japan, then found that P/2012 WX_32 was the same as an apparently asteroidal object discovered by the LINEAR asteroid survey on 2003 November 21 and 23 and given the minor-planet designation 2003 WZ_141.

Linking these two appearances of the comet provided an accurate orbit that Nakano could run back in time. His calculations showed that the P/2012 WX_32 = 2003 WZ_141 was the same as Tombaugh's comet of 1931. The comet is now renamed Tombaugh-Tenagra.

In 1931 Tombaugh had photographed the comet when it was at its closet to the sun, 2.45 AU. It was then only 15 degrees from where P/2012 WX_32 was found. The comet's orbital period back then was 9.05 years. The gravity of the planets has increased that to 9.10 years now. The 0.05-0.10 year difference from a neat number of years caused the comet to be increasingly badly placed for re-discovery at subsequent returns till recently.

Schwartz and Holvorcem, using equipment much more sensitive than Tombaugh's camera, found the comet three months before its closest approach to the sun. Its next return will be even better placed. It will still be a faint comet though, unless it has some sort of flare as it may have done in 1931.

-- by Ed from IAU Central Bureau Electronic Telegrams No. 3329 (2012 December 4) and No. 3342 (2012 December 13) and from Minor Planet Electronic Circular 2012-X13 (2012 December 4).

7. Tau Ceti's Planets

An international team of astronomers has discovered that Tau Ceti, one of the closest and most Sun-like stars, may host five planets -- with one in the star's habitable zone.

At a distance of twelve light-years Tau Ceti is the closest single star that has the same spectral classification as our Sun. Its five planets are estimated to have masses between two and six times the mass of the Earth -- making it the lowest-mass planetary system yet detected. One of the planets lies in the habitable zone of the star and has a mass around five times that of Earth, making it the smallest planet found to be orbiting in the habitable zone of any Sun-like star.

In the gravitational dance of a planet around a star, the planet does most of the moving. But the star too is tugged slightly to and fro as the planet orbits, and these subtle movements of the star show up as subtle shifts in the colour of the star's light we see from Earth.

This "radial velocity" measurement is a tricky one; stars' light changes also for a range of other reasons, and requires picking out the specifically planetary component from all this "noise".

The international team of astronomers, from the UK, Chile, the USA, and Australia, combined more than six-thousand observations from three different instruments and intensively modelled the data. The trick to honing the technique was to put in "fake planets" - to add signals into the messy data that planets should add - and find ways to reduce the noise until the fake planets became more and more visible in the data. In the process of doing that they found signals from real planets as well.

Over 800 planets have been discovered orbiting other worlds, but planets in orbit around the nearest Sun-like stars are particularly valuable. Steve Vogt from University of California Santa Cruz said: "This discovery is in keeping with our emerging view that virtually every star has planets, and that the galaxy must have many such potentially habitable Earth-sized planets. They are everywhere, even right next door! We are now beginning to understand that Nature seems to overwhelmingly prefer systems that have a multiple planets with orbits of less than one hundred days. This is quite unlike our own solar system where there is nothing with an orbit inside that of Mercury. So our solar system is, in some sense, a bit of a freak and not the most typical kind of system that Nature cooks up."

For more see http://star-www.herts.ac.uk/~hraj/tauceti http://www.bbc.co.uk/news/science-environment-20770103

-- From a University of Hertfordshire (U.K.) press release forwarded by Karen Pollard, and a BBC News and Environment posting pointed out by Pam Kilmartin.

8. Vega's Age and Spin Revised

Vega, the bright white star low in the north on our winter nights, may be more than 200 million years older than previously thought. That's according to new findings from the University of Michigan.

The researchers estimated Vega's age by precisely measuring its spin speed with a tool called the Michigan Infrared Combiner (MIRC), developed by John Monnier. MIRC collects the light gathered by six telescopes to make it appear to be coming through one that's 100 times larger than the Hubble Space Telescope. It is installed at the Georgia State Center for High Angular Resolution Astronomy Array located on Mt. Wilson, California.

The tool boosts resolution so astronomers can zoom in, relatively speaking, to observe the shape and surface characteristics of stars that would otherwise look like mere points even through the most powerful telescopes. By tracking stars' surface characteristics we can calculate how fast they rotate and deduce their inner workings.

At 25 light-years away, Vega is close on cosmic scales. A light-year is the distance light travels in one year.

About six years ago astronomers discovered that Vega is rotating so fast that it is nearly flinging itself apart. They haven't been able to agree on many of the related details, however. One of the debates centres on Vega's exact rotation rate, which is essential to gauge both its mass and age. Other controversies deal with Vega's tilt as viewed from Earth and the amount of turbulence in the system from roiling gases at the star¹s surface.

With MIRC's unprecedented resolution, Monnier and his colleagues have taken steps to rectify competing estimates of Vega's rotation rate and other properties. The new findings indicate that the star rotates once every 17 hours, rather than once every 12. The Sun's equator, for comparison, rotates much slower -- once every 27 days, or 648 hours. In addition to finding that Vega is older than previously thought, the Michigan group confirmed its mass to be just over two times the Sun's.

"Vega continues to challenge and surprise us," Monnier said. "We found out not too long ago that it has a disk of dusty debris, or a leftover solar system, around it. Then we found out it was a rapid rotator. It's a reference point for other stars, but it certainly isn't boring or normal."

The work will help astronomers build more accurate computer models of stars, so they can simulate those too far away to observe and gain a better understanding of their life cycles.

For the full paper in Astrophysical Journal Letters see http://dx.doi.org/10.1088/2041-8205/761/1/L3

-- From a University of Michigan in Ann Arbor press release forwarded by Karen Pollard.

[The press release doesn't say what former estimates of Vega's age were, sorry. - Ed.]

9. Radioactivity Important for Life?

Scattered around the Milky Way are stars that resemble our own Sun -- but a new study is finding that any planets orbiting those stars may very well be hotter and more dynamic than Earth.

That's because the interiors of any terrestrial planets in these systems are likely warmer than Earth -- up to 25 percent warmer, which would make them more geologically active and more likely to retain enough liquid water to support life, at least in its microbial form.

The preliminary finding comes from geologists and astronomers at Ohio State University who have teamed up to search for alien life in a new way.

They studied eight "solar twins" of our Sun -- stars that very closely match the Sun in size, age, and overall composition -- in order to measure the amounts of radioactive elements they contain. Those stars came from a dataset recorded by the High Accuracy Radial Velocity Planet Searcher spectrometer (HARPS) at the European Southern Observatory in Chile.

They searched the solar twins for elements such as thorium and uranium, which are essential to Earth's plate tectonics because they warm our planet's interior. Plate tectonics helps maintain water on the surface of the Earth, so the existence of plate tectonics is sometimes taken as an indicator of a planet's hospitality to life.

Of the eight solar twins they've studied so far, seven appear to contain much more thorium than our Sun -- which suggests that any planets orbiting those stars probably contain more thorium, too. That, in turn, means that the interior of the planets are probably warmer than ours.

For example, one star in the survey contains 2.5 times more thorium than our Sun, said Ohio State doctoral student Cayman Unterborn. According to his measurements, terrestrial planets that formed around that star probably generate 25 percent more internal heat than Earth does, allowing for plate tectonics to persist longer through a planet's history, giving more time for life to arise.

"If it turns out that these planets are warmer than we previously thought, then we can effectively increase the size of the habitable zone around these stars by pushing the habitable zone farther from the host star, and consider more of those planets hospitable to microbial life," said Unterborn, who presented the results at the American Geophysical Union meeting in San Francisco in early December.

"At this point, all we can say for sure is that there is some natural variation in the amount of radioactive elements inside stars like ours," he added. "With only nine samples including the Sun, we can't say much about the full extent of that variation throughout the galaxy. But from what we know about planet formation, we do know that the planets around those stars probably exhibit the same variation, which has implications for the possibility of life."

His advisor, Wendy Panero, associate professor in the School of Earth Sciences at Ohio State, explained that radioactive elements such as thorium, uranium, and potassium are present within Earth's mantle. These elements heat the planet from the inside, in a way that is completely separate from the heat emanating from Earth's core.

"The core is hot because it started out hot," Panero said. "But the core isn't our only heat source. A comparable contributor is the slow radioactive decay of elements that were here when the Earth formed. Without radioactivity, there wouldn't be enough heat to drive the plate tectonics that maintains surface oceans on Earth."

The relationship between plate tectonics and surface water is complex and not completely understood. Panero called it "one of the great mysteries in the geosciences." But researchers are beginning to suspect that the same forces of heat convection in the mantle that move Earth¹s crust somehow regulate the amount of water in the oceans, too.

"It seems that if a planet is to retain an ocean over geologic timescales, it needs some kind of crust recycling system, and for us that's mantle convection," Unterborn said.

In particular, microbial life on Earth benefits from subsurface heat. Scores of microbes known as archaea do not rely on the Sun for energy, but instead live directly off of heat arising from deep inside the Earth.

On Earth, most of the heat from radioactive decay comes from uranium. Planets rich in thorium, which is more energetic than uranium and has a longer half-life, would "run" hotter and remain hot longer, he said, which gives them more time to develop life.

As to why our solar system has less thorium, Unterborn said it's likely the luck of the draw. "It all starts with supernovae. The elements created in a supernova determine the materials that are available for new stars and planets to form. The solar twins we studied are scattered around the galaxy, so they all formed from different supernovae. It just so happens that they had more thorium available when they formed than we did."

Jennifer Johnson, associate professor of astronomy at Ohio State and co-author of the study, cautioned that the results are preliminary. "All signs are pointing to yes -- that there is a difference in the abundance of radioactive elements in these stars, but we need to see how robust the result is," she said.

Next, Unterborn wants to do a detailed statistical analysis of noise in the HARPS data to improve the accuracy of his computer models. Then he will seek telescope time to look for more solar twins.

Text & Images: http://researchnews.osu.edu/archive/hotplanet.htm

-- An Ohio State University press release forwarded by Karen Pollard.

10. How to Join the RASNZ

A membership application form and details can be found on the RASNZ website http://www.rasnz.org.nz/InfoForm/membform.htm. Please note that the weblink to membership forms is case sensitive. Alternatively please send an email to the membership secretary This email address is being protected from spambots. You need JavaScript enabled to view it. for further information.

The annual subscription rate is $75, not including the Yearbook. For overseas rates please check with the membership secretary, This email address is being protected from spambots. You need JavaScript enabled to view it..

11. Gifford-Eiby Lecture Fund

The RASNZ administers the Gifford-Eiby Memorial Lectureship Fund to assist Affiliated Societies with travel costs of getting a lecturer or instructor to their meetings. Details are in RASNZ By-Laws Section H.

For an application form contact the Executive Secretary This email address is being protected from spambots. You need JavaScript enabled to view it., R O'Keeffe, 662 Onewhero-Tuakau Bridge Rd, RD 2, TUAKAU 2697

12. Quotes

"One of the lessons of history is that nothing is often a good thing to do and always a clever thing to say." -- Will Durant.

"I respect faith, but doubt is what gets you an education." -- Wilson Mizner.

---------- Festive greetings to all our readers and best wishes for 2013.

There will be a January Newsletter -- if the Editor survives the end of the world and Christmas -- so keep those contributions pouring in.


Newsletter editor:

Alan Gilmore   Phone: 03 680 6000
P.O. Box 57   Email: This email address is being protected from spambots. You need JavaScript enabled to view it.
Lake Tekapo 7945
New Zealand