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Brymer Road,PO Box 9153,Hamilton 3289, New ZealandPh. 07-849-8522www.has.org.nz
INsIde tHIs Issue
2012: It’s going to be a good year!There’s been plenty of talk about what the year 2012 holds in store. Doomsday nonsense aside, it is going to be a great year for space and astronomy enthusiasts. Here are a few highlights to look forward to...
March 3: Mars at Opposition (the best time to view and photograph a planet).
March 13: Venus and Jupiter form a brilliant “double planet”.
April 15: saturn at Opposition.
June 4: Partial lunar eclipse.
June 6: transit of Venus (the last chance in your lifetime to see this).
August 6: Curiosity Rover arrives at Mars.
October 4-10: World space Week.
November 13: solar eclipse (partial in NZ, total in Australia).
december 3: Jupiter at Opposition.
december 21: eItHeR the Mayan calendar ends, the planets magically align, the sun passes through the galactic equator, havoc ensues and all life on earth is destroyed, OR nothing of note happens on this day.
december 25: Jupiter and the Moon form a nice Christmas ornament.
Also coming up in 2012...
• GRAIL should begin revealing secrets of the Moon’s structure and history.
• expect many more planets discovered by Kepler.
• NAsA will announce exploration missions for its discovery class program.
• Cassini makes 20 flybys of Titan and 10 flybys of Enceladus.
• MesseNGeR could discover ice in Mercury’s craters.
• spaceX’s dragon spacecraft should visit the Iss.
• NAsA will launch several radiation-studying missions.
• Continued political arguing over NAsA’s budget.
• China will push forward with its space station/moon base program.
Club Info & EventsPage 2 & 3
Stardate 2012Never been to a camp-out star party? Neither had we until this year—find out what it’s like for a first-timer.
Page 4
Comet LovejoyAn unexpected visitor graced our skies during december and January.
Page 6
Planets are PlentifulA new study confirms what scientists have long suspected: Planets around stars are the norm. It appears the Milky Way has at least one planet per star on average (probably many more).
Page 7
Glimpses of Interstellar MaterialNAsA’s IBeX has found that there’s more oxygen in our solar system than there is in the nearby interstellar material.
Page 8 But wait, there’s more...
Page 9
SPECIAL EVENT this Monday (Waitangi Day):Pot luck dinner & BBQ at Hamilton Observatory. See page 3 for details.
Monthly Newsletter, February 2012
HAMILTON ASTRONOMICAL SOCIETY
HAS
facebook.com/hasnz
CLuB INFORMAtION
BuLLetIN INFORMAtION
Presidentdave Owen (07) [email protected]
Vice PresidentsWalter smithson (07) [email protected]
Julian Pescud (07) 854-8048
SecretaryBruce Griffiths (07) [email protected]
TreasurerIan transom (07) [email protected]
CommitteeRoss Barnett (07) [email protected]
Robin Holdsworth (07) [email protected]
darren [email protected]
2
All copy for publication must be received two weeks before the beginning of the month of publication. Please use plain text and attach images separately.
Opinions expressed in this bulletin do not necessarily reflect the official position of Hamilton Astronomical society. Contact the editor if you have any queries about this publication.
editor: dave Owen (07) [email protected]
uPCOMING eVeNts
Society Night: Monday, Feb 6th, 5:30pm. BBQ dinner (see page 3).
Ian Transom presents a talk on the history of spaceflight: “Wernher von Braun & sergei Korolev: V2 to saturn V”
Public Night: Wed 15th Feb, 8:30pm
Committee Meeting: Monday, Feb 13th, 7:30pm
edItORIAL
Hi everyone,
2012 is shaping up to be a great year for our society. Hard-working committee members have already started preparations (see page 3). the observatory is looking shiny and new, the first public night of the year has already happened, and there are plenty of interesting astronomical events ahead.
I’d really like to encourage you all to come along on Monday evening for the BBQ and pot luck dinner. If you have any questions about the event, or if you need help with transport, please email me ([email protected]) or phone 07-870-1966.
We are actively seeking new ideas for making our society nights more enjoyable for all ages and interests. We’re especially keen to hear from younger members about what we can do for you. several people have suggested a dedicated “young astronomers” group. If this sounds like something you’d like to support, please let us know.
It’s only a few months until the transit of Venus and we’re considering ideas about how our society should be involved in this historic event.
Later in the year there’s a total solar eclipse visible from North Australia. A group of Kiwi amateur astronomers is going, including me and my family. If you’d like to come, let me know and I can help put you in touch with the group and let you know where we’re staying.
And lastly, Ian transom alerted me to a charming video of two Canadian teenagers sending a Lego man 24 km into the stratosphere aboard a weather balloon: www.youtube.com/watch?v=MQwLmGR6bPA I’ll bring the video to the society night on Monday.
Clear skies,dave Owen
AstRONOMy & sPACe tRIVIA
edmond Halley never saw the famous comet that bears his name. In 1705 he predicted that the comet would appear in 1758, but he died in 1742 — 16 years too early to witness it.
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Working Bee Worth the Effort
HAs Committee members were denied a sleep-in on saturday, 28th January 2012. Bright and early the team set to work tidying up the observatory in preparation for the coming year’s activities.
the focus was the library, kitchen area and eyepiece room, which had become like the tARdIs in its ability to contain more volume of matter than appears possible from the outside.
It’s never easy saying goodbye to old faithful equipment, but realistic decisions had to be made and by lunchtime one trailer-load and one ute-load of gear was on its way to the recyclers.
One the plus side, a few forgotten treasures were found, including some hand-drawn posters and photographic slides dating back decades. If you’re interested in having a look, ask one of the committee members at any society night.
the kitchen area is now looking much roomier and more inviting. thanks to everyone who helped with the cleanup—it was a fabulous effort.
Invitation: Pot Luck dinner & BBQ on Monday!
Above: Muddling through mounds of miscellaneous memorabilia.
Below: the “pile of obsolescence” included 14 CRt monitors which were loaded into Walter’s trailer.
to all members... Please join us at Hamilton Observatory, 5:30pm this Monday 6th Feb (Waitangi day) for an informal pot luck dinner and barbecue. Families are very welcome.
If you don’t normally come to society nights, this is your chance to have a look around and see what we do. Committee members will be on hand to welcome everyone and make sure you feel included. We’d also like to hear your ideas about what the society could be doing for its members, and any ideas you have for our future.
If you can’t stay for the whole evening, that’s fine—we understand that it’s a school night. We’d still love to see you for as long as you can be there.
If you do stay, you’ll be treated to Ian transom’s talk on the history of spaceflight.MONDAY 6th February, 5:30pm
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This year I finally attended my first star party and, to my surprise, managed to convince my family to join me. the event was Stardate 2012, a weekend gathering of astronomers organized by the Phoenix Astronomical society. It was held at a fully reserved camping ground near Hastings, on the 20th to 22nd January.
there were two accommodation options: shared bunk rooms or tent spots. When booking, we only had a brief description and no photos so it was hard to imagine what the bunk rooms were like. We opted for a tent spot which was the right decision - the bunk rooms turned out to be unsuitable for families.
We arrived mid-afternoon on Friday and pitched our tent in a nice spot. Quickly meeting some of our neighbours was a good move, as they were veteran star partiers who helped us find our way around.
the opening ceremony was surprisingly short and left me with the vague feeling that I didn’t really have enough information. Oh well, people seemed very friendly and I was sure we’d be able to ask for help as needed.
The first presentation was an impressive showcase of images from the 2011 RAsNZ astrophotography competition, hosted by well-known Gisborne astronomer John drummond. this was also the session in which I learned just how uncomfortable a seat can be. As soon as the first talk was over I went back to the tent and grabbed a pillow to sit on. I never went to another talk without it.
After a tenuously relevant lecture about skin cancer, John drummond was back with an interesting talk on elliptical and spiral galaxies.
then came the reason we were all there - telescope viewing. this was held in the lower paddock, where everyone with a telescope sets up
and invites everyone else to have a look.
4yO Floyd was asleep by this time, but 6yO Jessica was keen to go observing. Unfortunately the first six telescopes we visited were all pointed at M42! I guess that’s sort of understandable as people were getting themselves established, but perhaps a little coordination might have been a good idea. Although it was fun chatting to people along the way, after the sixth telescope Jessica was tired, a little disappointed (M42 is nothing new to her) and ready for bed.
Half an hour later I was back by myself and hoping for something more interesting. sadly, this is where I got my biggest disappointment and made my biggest mistake.
the vibe had changed. Most of the “good” telescopes were surrounded by small groups of people huddled together and speaking in low voices. Feeling like a complete loner, I tried my best to insert myself into a couple of groups or even get a closer look to see what was going on. In the dark this wasn’t easy. I have no doubt that these were friendly people but they didn’t seem to be very mindful of newbies and I just couldn’t seem to get a look-in anywhere. sure, I could have been more forceful and I would have been welcomed. But I was still finding my way and I didn’t feel comfortable with the situation.
so, less than two hours after lecturing my family about how important it is to seize every observing opportunity, I gave up and went to bed with the plan of finding a “buddy” to help me the next night. What was I thinking?
the next two nights were clouded out and there were no more observing sessions. Curse my idiocy.
saturday morning featured the first of two sessions for children: “Constellations and Asterisms”. Remarkably, this managed to hold my kids’ attention for almost
ninety minutes. they’ve still got the handouts and pictures of asterisms they designed themselves.
At 12 noon we set off on the telescope trail, in which the owners of each telescope talked a bit about their gear. this was the highlight of the entire weekend for me, despite being way too hot in the midday sun.
It occurred to me that a similar sort of trail would have been very useful the previous night. Instead of letting people try to find their own way around the viewing scopes, it would have been nice to have had a guide to help with introductions.
I attended about half the remaining saturday presentations and was fairly satisfied with all of them. The best was the evening talk given by Ian Cooper and stephen Chadwick who have co-written a book called “Imaging the southern skies”. the book is due out later this year and I’ll be buying a copy. I was stunned at the quality of stephen’s photographs, and equally impressed by Ian’s knowledge. the only downside is that I’m pretty sure the talk included every single photo from the book (it was a long talk).
With no observing possible there was a movie on offer, but the thought of sitting on those bench seats a minute longer was too much. I went to bed.
sunday morning included a rocket-launching session for all ages. It was gold, and I can’t thank George Moutzouris enough for providing the weekend highlights for my kids.
A buy-and-sell session over lunch was enjoyable and informative, although there wasn’t a huge amount of stuff for sale.
the remaining presentations were all reasonably rewarding but finished on an embarrassing note for us. Our kids really wanted to see the Mars presentation, and since they’re well-hardened to watching grown-
Stardate: An account of my first star partyby Dave Owen
5
George Moutzouris runs a rocket-launching session for kids.
up space talks I thought it would be okay. As it turned out, the talk was more advanced than we’d expected and involved a lot of technical text being read from the screen. Our kids became too fidgety and we had to walk out, at which time we discovered the world’s noisiest door. I assume the entire hall was glaring at us but we didn’t look back as we slunk away.
On a more positive note, I went for a walk at 2 a.m. and was surprised to find a clear sky. Three other people were about, so one of them brought out his 8” dob and we did a bit of observing.
All in all, despite a few missteps I count our first Stardate as a success. the biggest surprise was my family’s response—I had been nervous about how bored they would get but I needn’t have worried. they’ve suggested that we all go back next year, and we probably will.
Tips learnt from my first Stardate:
(1) Arrive by lunch time on Friday if you want a good tent spot.
(2) Ask for help and guidance. you don’t get a lot from the organizers but that’s okay once you realize it’s more a case of everyone helping everyone else. don’t make my mistake and be too shy.
(3) take a cushion for the talks. Before attending a talk, try to ascertain the technical level (they vary greatly).
(4) the kitchen closes without warning on Monday morning. Retrieve all your food and other belongings before then.
(5) Treat your first star party as a learning experience.
If you’re interested in going to next year’s stardate, feel free to contact me ([email protected]) and I’ll be your “buddy”.
HAs members talking about their telescopes.Above: dave BrockRight: trevor Vowles
One of the weekend highlights was the telescope trail.
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Comet Lovejoy provided astro-photographers with a superb subject over the Christmas-New year holidays -- those who had clear dawn skies, that is. Not unexpectedly, the comet’s nucleus disintegrated during its close approach to the sun’s surface. the dust from its fragmentation produced the long narrow tail that delighted sky watchers.
A puff of dust from a comet’s “dirty snowball” nucleus spreads away from the sun along a line. the speed the dust moves away depends on the particle size. the gravity acting on a particle varies inversely as the square of the distance from the sun. the intensity of sunlight varies in the same way but with an outward push. so a particle “feels” a lesser gravitational attraction toward the sun due to the sunlight pressure. It thus moves in a different orbit, as though the sun’s gravity was weakened. the smaller the particle, the greater is the acceleration away from the sun due to light pressure.
the line or band of dust is called a synchrone (“same time”) as all the dust was ejected together. By analysing the brightness and angles of synchrones it is possible to calculate when the dust was emitted and how big the particles are.
Zdenek sekanina of the Jet Propulsion Laboratory has done this analysis for Comet Lovejoy. Writing in Central Bureau for Astronomical telegrams electronic telegram No. 2967, sekanina found that most of Comet Lovejoy’s tail was the product of a major outburst, or a series of outbursts, that peaked during a relatively short period of time centred on dec. 17.6 +/-0.4 ut. that was 1-2 days after perihelion.
the bright part of the synchrone contained dust particles larger than about 30 microns in diameter (with radiation pressure acceleration parameter, beta, < 0.04) on dec. 19-20, larger than about 40 microns (beta < 0.03) on dec. 24, larger than
about 80 microns (beta < 0.015) on dec. 29, and larger than about 120 microns (beta < 0.01) on Jan. 3 (when the bright part is understood to be the northern-most 40’ of the feature).
the synchrone approximately coincided with the line of symmetry to the much fainter quasi-parabolic envelope of additional ejecta, consisting of a smaller number of dust particles that -- upon their ejection (on or before dec. 17.6) -- acquired lateral velocities mostly several tens of m/s, with an upper limit of 200 m/s. the sharp spike at the sunward end of the synchrone, the site of the most massive fragments (possibly boulder-sized or larger) are located, shows that their separation velocities were extremely low.
sekanina noted that no images showed a second tail produced by new dust from the nucleus. It would have been expected to the south of the synchrone, making an angle of 5-6 deg to it. Also there was a dramatic change in the comet’s appearance between dec. 19 and 20. the comet’s nuclear condensation -- the bright cloud around the nucleus -- disappeared on dec. 20. All this suggests that the comet sustained a severe damage to its nucleus as the
source of activity.
sekanina concluded: “the outburst(s) apparently constituted part of the rapidly-progressing process of cataclysmic fragmentation that was continuing past dec. 19.4 ut but was essentially completed by dec. 20.3. the drop in brightness from dec. 20 on is, in this scenario, understood as reflecting basically the rate of dispersal in space of the dust ejecta released during the dec. 16-20 period of the comet’s activity.”
“It appears that, brightness-wise, C/2011 W3 is rivalling the headless sungrazer C/1887 B1, whose tail was visually detected until about 19 days after perihelion. However, C/2011 W3 is doing a little better in terms of the post-perihelion survival of an active nucleus, as comet C/1887 B1 was found to have lasted for only about 6 hours after its perihelion passage (sekanina 1984, Icarus 58, 81).”
sekanina’s analysis used two images taken by J. ebr et al on dec. 19.37 and 20.33 ut with a 0.3-m f/10 Schmidt-Cassegrain reflector, a robotic remotely-controlled telescope located at the Pierre Auger Observatory at Malargue.
Comet LovejoySource: RASNZ
Comet Lovejoy, 2012 Jan 5 UT, by John Drummond (www.possumobservatory.co.nz).
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An international team, including three astronomers from the european southern Observatory (esO), has used the technique of gravitational microlensing to measure how common planets are in the Milky Way. After a six-year search that surveyed millions of stars, the team concludes that planets around stars are the rule rather than the exception. the results will appear in the journal Nature on 12 January 2012.
Over the past 16 years, astronomers have detected more than 700 confirmed exoplanets and have started to probe the spectra and atmospheres of these worlds. While studying the properties of individual exoplanets is undeniably valuable, a much more basic question remains: how commonplace are planets in the Milky Way?
Most currently known exoplanets were found either by detecting the effect of the gravitational pull of the planet on its host star or by catching the planet as it passes in front of its star and slightly dims it. Both of these techniques are much more sensitive to planets that are either massive or close to their stars, or both, and many planets will be missed.
An international team of astronomers has searched for exoplanets using a totally different method — gravitational microlensing — that can detect planets over a wide range of mass and those that lie much further from their stars.
Arnaud Cassan (Institut dʼAstrophysique de Paris), lead author of the Nature paper, explains: “We have searched for evidence for exoplanets in six years of microlensing observations. Remarkably, these data show that planets are more common than stars in our galaxy. We also found that lighter planets, such as super-earths or cool Neptunes, must be more common than heavier ones.”
the astronomers used observations, supplied by the PLANet and
OGLe teams, in which exoplanets are detected by the way that the gravitational field of their host stars, combined with that of possible planets, acts like a lens, magnifying the light of a background star. If the star that acts as a lens has a planet in orbit around it, the planet can make a detectable contribution to the brightening effect on the background star.
Jean-Philippe Beaulieu (Institut d’Astrophysique de Paris), leader of the PLANet collaboration adds: “the PLANet collaboration was established to follow up promising microlensing events with a round-the-world network of telescopes located in the southern hemisphere, from Australia and south Africa to Chile. esO telescopes contributed greatly to these surveys.”
Microlensing is a very powerful tool, with the potential to detect exoplanets that could never be found any other way. But a very rare chance alignment of a background and lensing star is required for a microlensing event to be seen at all. And, to spot a planet during an event, an additional chance alignment of the planet’s orbit is also needed.
Although for these reasons finding a planet by microlensing is far from an easy task, in the six year’s worth of microlensing data used in the analysis, three exoplanets were actually detected in the PLANet and OGLe searches: a super-earth, and planets with masses comparable to Neptune and Jupiter. By microlensing standards, this is an impressive haul.
In detecting three planets, either the astronomers were incredibly lucky and had hit the jackpot despite huge odds against them, or planets are so abundant in the Milky Way that it was almost inevitable.
the astronomers then combined information about the three positive exoplanet detections with seven additional detections from earlier work, as well as the huge numbers of non-detections in the six year’s worth of data — non-detections are just as important for the statistical analysis and are much more numerous. the conclusion was that one in six of the stars studied hosts a planet of similar mass to Jupiter, half have Neptune-mass planets and two thirds have super-earths. the survey was sensitive to planets between 75 million kilometres and 1.5 billion kilometres from their stars (in the solar system this range would include all the planets from Venus to saturn) and with masses ranging from five times the Earth up to ten times Jupiter.
Combining the results suggests strongly that the average number of planets around a star is greater than one. they are the rule rather than the exception.
“We used to think that the earth might be unique in our galaxy. But now it seems that there are literally billions of planets with masses similar to earth orbiting stars in the Milky Way,” concludes daniel Kubas, co-lead author of the paper.
More info: bit.ly/AFprxG
Planet Population is PlentifulSource: ESO
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A great magnetic bubble surrounds the solar system as it cruises through the galaxy. the sun pumps the inside of the bubble full of solar particles that stream out to the edge until they collide with the material that fills the rest of the galaxy, at a complex boundary called the heliosheath. On the other side of the boundary, electrically charged particles from the galactic wind blow by, but rebound off the heliosheath, never to enter the solar system. Neutral particles, on the other hand, are a different story. they saunter across the boundary as if it weren’t there, continuing on another 7.5 billion miles for 30 years until they get caught by the sun’s gravity, and sling shot around the star.
there, NAsA’s Interstellar Boundary explorer lies in wait for them. Known as IBeX for short, this spacecraft methodically measures these samples of the mysterious neighborhood beyond our home. IBeX scans the entire sky once a year, and every February, its instruments point in the correct direction to intercept incoming neutral atoms. IBeX counted those atoms in 2009 and 2010 and has now captured the best and most complete glimpse of the material that lies so far outside our own system.
the results? It’s an alien environment out there: the material in that galactic wind doesn’t look like the same stuff our solar system is made of.
“We’ve directly measured four separate types of atoms from interstellar space and the composition just doesn’t match up with what we see in the solar system,” says eric Christian, mission scientist for IBeX at NAsA’s Goddard space Flight Center in Greenbelt, Md. “IBeX’s observations shed a whole new light on the mysterious zone where the solar system ends and interstellar space begins.”
More than just helping to determine the distribution of elements in the galactic wind, these new
measurements give clues about how and where our solar system formed, the forces that physically shape our solar system, and even the history of other stars in the Milky Way.
In a series of science papers appearing in the Astrophysics Journal on January 31, 2012, scientists report that for every 20 neon atoms in the galactic wind, there are 74 oxygen atoms. In our own solar system, however, for every 20 neon atoms there are 111 oxygen atoms. that translates to more oxygen in any given slice of the solar system than in the local interstellar space.
“Our solar system is different than the space right outside it and that suggests two possibilities,” says david McComas the principal investigator for IBeX at the southwest Research Institute in san Antonio, texas. “either the solar system evolved in a separate, more oxygen-rich part of the galaxy than where we currently reside or a great deal of critical, life-giving oxygen lies trapped in interstellar dust grains or ices, unable to move freely throughout space.” either way, this affects scientific models of how our solar system – and life – formed.
studying the galactic wind also provides scientists with information about how our solar system interacts with the rest of space, which is congruent with an important IBeX goal. Classified as a NASA Explorer Mission -- a class of smaller, less expensive spacecraft with highly focused research objectives -- IBeX’s main job is to study the heliosheath, that outer boundary of the solar system’s magnetic bubble -- or heliosphere -- where particles from the solar wind meet the galactic wind.
Previous spacecraft have already provided some information about the way the galactic wind interacts with the heliosheath. ulysses, for one, observed incoming helium as it traveled past Jupiter and measured it traveling at 59,000 miles per hour.
IBeX’s new information, however, shows the galactic wind traveling not only at a slower speed -- around 52,000 miles per hour -- but from a different direction, most likely offset by some four degrees from previous measurements. such a difference may not initially seem significant, but it amounts to a full 20% difference in how much pressure the galactic wind exerts on the heliosphere.
“Measuring the pressure on our heliosphere from the material in the galaxy and from the magnetic fields out there,” says Christian, “will help determine the size and shape of our solar system as it travels through the galaxy.”
these IBeX measurements also provide information about the cloud of material in which the solar system currently resides. this cloud is called the local interstellar cloud, to differentiate it from the myriad of particle clouds throughout the Milky Way, each traveling at different speeds. the solar system and its heliosphere moved into our local cloud at some point during the last 45,000 years.
since the older ulysses observations of the galactic wind speed was in between the speeds expected for the local cloud and the adjacent cloud, researchers thought perhaps the solar system didn’t lie smack in the middle of this cloud, but might be at the boundary, transitioning into a new region of space. IBeX’s results, however, show that we remain fully in the local cloud, at least for the moment.
“sometime in the next hundred to few thousand years, the blink of an eye on the timescales of the galaxy, our heliosphere should leave the local interstellar cloud and encounter a much different galactic environment,” McComas says.
More information: 1.usa.gov/zgzyGZ
Glimpses of the Interstellar Material Beyond our solar systemSource: NASA
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The Sun unleashes an X1.8 class flare: 1.usa.gov/zRuRcX
Kepler Announces 11 Planetary systems Hosting 26 Planets: 1.usa.gov/zj1hCN
NAsA Mars Rover Finds Mineral Vein deposited by Water: 1.usa.gov/ssHe9h
VLt Finds Fastest Rotating star: bit.ly/u9JxA4
NAsA telescopes Help Find Rare Galaxy at dawn of time: 1.usa.gov/uyt7Ry
esO’s VIstA telescope shows the Helix in New Colours: bit.ly/x7twVb
Phobos-Grunt Failure due to Computer Problems, Cosmic Rays: bit.ly/w9GpBk
Phil Plait debunks Newt Gingrich’s moon base plan: bit.ly/y8pOjX
New Research suggests Fomalhaut b May Not Be a Planet After All: bit.ly/xh5PHj
stunning new high-resolution “Blue Marble” image: 1.usa.gov/w8m28V
Cassini takes a Closer Look at titan’s sand dunes: bit.ly/AyVGZw
Invisible Galaxy Could be Made up entirely of dark Matter: bit.ly/y5Bpzr
spaceX delays upcoming 1st dragon Launch to Iss: bit.ly/zxshz2
NAsA’s twin Grail spacecraft Reunite in Lunar Orbit: 1.usa.gov/udeeC3
Independent researchers find no evidence for arsenic life in Mono Lake: bit.ly/wdekkz
Russia Confirms Delay for Next Soyuz Launches to ISS: bit.ly/y0fAm2
New Research Casts doubt on the Late Heavy Bombardment: bit.ly/wR8Hu3
NAsA study solves Case of earth’s ‘Missing energy’: 1.usa.gov/xcJrFg
the Wild early Lives of today’s Most Massive Galaxies: bit.ly/A5PJwt
Vesta Likely Cold and dark enough for Ice: 1.usa.gov/yaeKJv
Before they Were stars: New Image shows space Nursery: 1.usa.gov/xQLVbN
Hayabusa 2 Mission Approved by Japanese Government: bit.ly/zRNpv4
Does Life on the Seafloor Predict Life on Other Worlds? bit.ly/yjdfeL
But wait, there’s more...
Royal Astronomical Society of New ZealandAnnual Conference 2012
Carterton, June 15 to 17Hosted by the Phoenix Astronomical society
For details visit www.rasnz.org.nz
The Night Sky in February 2012
three planets are bright ‘stars’ in a rich evening sky. Venus and Jupiter appear in the west soon after sunset as Mars rises in the east. North of the zenith is sirius, the brightest true star. south of overhead is Canopus, the second brightest star.
Brilliant silver Venus appears low in the west soon after sunset. It looks like a tiny gibbous moon. It is slowly catching us up but is still around 150 million km away. It sets around 10 pm. Venus is the same size as earth.
Jupiter, also in the west, shines with a steady golden light. A telescope will easily show the four bright moons first seen by Galileo in 1610. Jupiter is 780 million km from us now.
Orange-red Mars rises around 10:30 at the beginning of February. By the end of the month it is up at dusk. We pass it by at the beginning of March at a distance of 100 million km. that’s nearly twice as far away as it was at the close ‘opposition’ of 2003. (It’s called an opposition because the planet is opposite the sun when closest to earth.) so Mars appears small in a telescope: one-third the size of Jupiter. Mars is half the diameter of earth and one-tenth earth’s mass.
saturn (not shown) rises in the east around midnight at the beginning of the month. It is up at 10 pm by the end of February. It is below and left of spica, a star a little fainter than saturn.
Credit: RASNZ/Alan Gilmore
