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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. Stu Parker Invited to Supernova Conference
2. RASNZ Conference 2011
3. The Solar System in June
4. Annual General Meeting Agenda
5. TTOS5 to Unveil New Video Time Inserter
6. Bernard Mills
7. Gravity Probe B Confirms Einstein
8. Voyager Set to Enter Interstellar Space
9. Newly Discovered Tiny Companion to Earth
10. Amateurs Video Blinking Asteroid
11. HST Images Colourful Galaxies
12. Gifford-Eiby Lecture Fund
13. Kingdon-Tomlinson Fund
14. How to Join the RASNZ
15. Quotes

1. Stu Parker Invited to Supernova Conference

Stuart Parker of Oxford, Canterbury, celebrated his 13th supernova discovery on April 29. It was the 18th success of the Australasian Backyard Observatory Supernova Search (BOSS) team that started in 2009.

The productivity of BOSS has led to Stu being invited to attend the Supernovae and their Host Galaxies conference in Sydney in June. Stu kindly provided the following details. ----------

"Supernovae and Their Host Galaxies" is the 4th in the annual Southern Cross Astrophysics Conference Series. It runs from June 20 to 24 at the Australian National Maritime Museum at Darling Harbour in Sydney.

The conference was announced six months ago. Our amateur supernova search group (BOSS) was asked if we wish to attend. As this is a professional event we had to wait to see if there was enough room for us. After a long wait we were allowed one seat at the conference, so I will be attending.

It is a large gathering of some of the best minds in the field of supernova and transients. The latest theories and findings will be discussed. It features speakers such as Carles Badenes, Poonam Chandra, Roger Chevalier, Luc Dessart, and Alex Filippenko (of the TV show "The Universe").

Some of the topics that will be covered are: the many different paths to a supernova explosion; the progenitors of supernovae; supernova remnants; the relationships between the properties of supernovae and their host galaxies; supernovae as tracers of star formation; unusual supernovae; unexplained transients; current and future transient surveys.

I am very much looking forward to going. We have been asked to present a poster showcasing our group and what we have done to date. It is a bit unusual for an amateur group to be able to attend a professional gathering so it will be a great experience. This is a 3½ day, 8 hours per day conference so there will be a lot of information. I hope to learn a lot and make some great contacts with people that have done spectra for some of my supernova discoveries.

--------- For more on Stu's methods and results see http://parkdale-supernova-factory.webs.com/

2. RASNZ Conference 2011

Goodness, people do like leaving things till the last minute.... By Easter our registrations were down on expectations. But there has been a late surge, and numbers are close to normal. It's not too late to register - the War Memorial Convention centre in Napier is plenty big enough.

Due to the earthquake, some of our Christchurch regulars and the students are unable to join us this year. We completely understand the position they are in (luckily those of us on the SCC suffered only minor damages), and we look forward to them being able to return to Conference in force in 2012.

The programme is full - you can access all the information, registration forms on the Society Webpage - www.rasnz.org.nz - and if there is any information you want that is not there, please email: This email address is being protected from spambots. You need JavaScript enabled to view it. and one of us will get back to you quickly. Please get any questions to us before Tuesday, 24 May, however, as after that date we too will be en route to Napier. If you are in doubt about coming along my advice is - just do it. It will be a weekend of great value.

Numbers are also good for the 5th Trans-Tasman Symposium on Occultations (26-27 May), and the Photographic Workshop with David Malin (30 May), but spaces are still available.

Just in case you are wondering who the Standing Conference Committee (SCC) is etc, we are: Dennis Goodman (Chair), Pauline Loader, Brian Loader, Orlon Petterson, and Tim Homes. Also, Warwick Kissling is programme assistant to the SCC.

We are appointees of the RASNZ Council, and report to and are answerable to Council. We welcome all constructive feedback. Conference attendees will receive a feedback questionnaire in their Conference folder when they arrive at the venue, and SCC members will want to collect the completed questionnaires at the conclusion of Conference. Your feedback will help us improve conferences in the future.

Ok - see you in napier.

Dennis Goodman, Chair, RASNZ Standing Conference Committee

3. The Solar System in June

The usual notes on the visibility of the Planets for June 2011 are on the RASNZ web site: http://www.rasnz.org.nz/SolarSys/Jun_11.htm. Notes for July 2011 will be on line in a few days.

The southern midwinter solstice, with the sun furthest north and lowest at midday is at 5.17am on June 22, NZST.

The planets in june

After their close clustering in the morning sky during May, the four planets will disperse in June. Mercury will disappear into the morning twilight very early in the month and Venus will get to be very low in the dawn sky. Mars will also maintain its rather low altitude, but higher than Venus while Jupiter will get steadily higher.

Saturn continues to be a well placed object of the evening sky.

A total eclipse of the moon occurs on the morning of June 16 (NZST). The moon enters the penumbra just after 5.24 am, NZST. It starts moving into the total shadow of the umbra almost an hour later. By then the moon will be getting low in NZ. The eclipse becomes total just after 7.22am but will be close to setting in NZ, especially in the north. Mid eclipse is at 8.13 am, by which time the moon will be set in all of NZ north of Timaru. It sets 10 minutes later in Dunedin and 20 minutes later in Invercargill. The end of the total eclipse will not be visible in any part of NZ.

Australia will have a better view but even there, in the east, the moon will set before the end of the total eclipse. Only in the west of Australia are all stages of the eclipse visible.

A partial eclipse of the Sun on June 1 is only visible from Arctic regions of the northern hemisphere.

Morning sky

Mercury is 7° below and a little to the right of Venus on the morning of June 1. A very thin sliver crescent moon, only 1% lit, will be 4.5° below and slightly left of Mercury. 30 minutes before sunrise Mercury will be some 6° above the horizon. At magnitude -0.9 it should be possible to detect the planet, especially using binoculars, sweeping down and to the right of Venus. The moon, with an altitude only 2° will be harder to locate.

Mercury´s elongation from the sun will decrease steadily over the next few days until it is at superior conjunction on June 13. It will then be on the opposite side of the Sun, 198 million km from Earth. At this conjunction Mercury passes just over one solar diameter north of the Sun.

After conjunction Mercury will become an evening object, setting after the Sun. The planet is too close to the Sun for observation for most of the remainder of the month. By the end of June, it will set 80 minutes after the Sun: 40 minutes after sunset, Mercury will be about 6° above the horizon, well round from west towards northwest. At magnitude -0.5 it is likely to be a binocular object. July will offer better opportunities of seeing Mercury in the evening sky.

Venus will be following Mercury back towards the sun during June. On the 1st its altitude is about 13°, 20 minutes before the sun rises. This altitude will have reduced to a mere 5° on June 30. On the latter morning, the moon, a very thin crescent only 2.5% lit, will be 5° to the left of, and a little higher than Venus.

Venus is on the far side of the Sun to the Earth, moving towards superior conjunction in August. As a result, we see it nearly fully lit, 93% early in June and 97% by the end. Being nearly fully lit compensates for its relatively large distance, 250 million km at the end of June, and consequent small apparent size, 10 arc-seconds. These factors combine to maintain the brightness of the planet.

Mars continues in June as a lowish object in the dawn sky. The time at which it rises ranges from about 5.20 am in the north of NZ to a few minutes after 6 am in the south and only advances by a few minutes during the month. Once the planet is at a reasonable altitude it will be readily visible at magnitude 1.3 to 1.4 until about 40 minutes before sunrise.

At the beginning of June, Mars will be about 12° up 45 minutes before sunrise, some 4° to the upper left of Venus. By the end of June and again 45 minutes before sunrise, Mars will be about 1° higher to the northeast. It will then be in Taurus just about half way between the Pleiades and Aldebaran, magnitude 1.0 so slightly brighter than Mars. Aldebaran being a red star will have a similar colour to Mars. On the morning of the 29th the 7% lit crescent moon will be 2.5° below Mars.

Jupiter, by contrast with Mars, rises steadily earlier during June, at or soon after 4 am in much of NZ on the 1st, about 80 minutes earlier at the end of the month. Thus it will be getting reasonably high in the morning sky in the early twilight.

Jupiter starts the month in Pisces, but by June 8 it will be in Aries. The planet does not pass very close to any bright stars during the month. On the morning of June 26, the 29% lit waning moon will be 7.5° to the left of Jupiter


Saturn, unlike the other planets, will be in the evening sky, the only planet visible there throughout the month, apart from a possible glimpse of Mercury in the dusk at the end of June. Saturn is stationary mid June, and shows little movement throughout the month. In June, Saturn will be some 14° from Spica which, at magnitude 1.1, is the brightest star in Virgo. Early evening, especially at the beginning of June, Spica will be to the right of Saturn. By mid to late evening, the rotation of the sky will see the star nearly above Saturn.

Another star gamma Virginis, Porrima, will be much closer to Saturn during June. At its least, the distance between the two will be only half the diameter of the full moon, just over 15 arc-minutes. Saturn will be above Porrima. At magnitude 3.4 Porrima is not as bright as Spica, but is still visible to the unaided eye from reasonably dark sites.

The tilt of Saturn´s rings towards the Earth is at a minimum for the year in the first part of June, 7.3°. By the end of the month they will be beginning to open again.

The 65% moon will be 8° from Saturn on the evening of June 10. The moon will be to the left of Saturn.


Uranus is another a morning object, rising about 2am at the beginning of June and near midnight at the end. The planet is in Pisces with its distance from Jupiter increasing from 25° to 30° during the month. Uranus´ magnitude is 5.8 by the end of June.

Neptune, magnitude 7.9, is in Aquarius during June. It is some 34° ahead of Uranus along the ecliptic and rises nearly 3 hours earlier. It is stationary on June 3.

Brighter asteroids:

(1) Ceres is a morning object in Aquarius about 14° from Uranus early in June. Being further south Ceres rises about 1 hour earlier. Ceres moves into Cetus on June 8 and ends the month 10° from 2.0 magnitude beta Ceti. The asteroid brightens from magnitude 9.1 to 8.8 in June.

(4) Vesta rises mid evening during June so achieves a reasonable altitude by late evening, especially later in the month. The asteroid is in Capricornus and brightens from magnitude 6.8 to 6.3. Its brightening means that for the next 4 months Vesta is going to be an easy binocular target.

Vesta starts June only 20´ from 4.3 magnitude iota Cap. At the end of June it will be less than 2° from epsilon Cap, mag 4.5. But the asteroid is stationary on June 24, so by June 30 will be turning away from Epsilon.

More details and charts for these minor planets can be found on the RASNZ web site. Follow the link to asteroids 2011.

-- Brian Loader

4. Annual General Meeting Agenda

The 2011 Annual General Meeting of the Royal Astronomical Society of New Zealand will be held at 4.30pm on Saturday 28 May 2011 at the Napier War Memorial Conference Centre on Marine Parade, Napier. ----------------

Royal astronomical society of new zealand 88th annual general meeting

Agenda:

  1. Apologies.
  2. Respect for Deceased Members.
  3. Greetings to Absent Members.
  4. Minutes of the 87th AGM held in Dunedin
  5. Matters arising from the Minutes.
  6. Annual report of council for 2010
  7. Annual accounts for 2010
  8. Election of Auditor.
  9. Election of Honorary Solicitor.
  10. General Business as allowed for in the rules.

Minutes of the 87th AGM (2010) are available on the RASNZ web site at http://www.rasnz.org.nz/minutes/1005AGM.pdf

The Annual Report of Council and the Annual Accounts for the year 2010 have been printed in the March 2011 issue of Southern Stars.

Rory O´Keeffe Executive Secretary 19 April 2011

------------------ The AGM and Affiliated Society Minutes for 2010 have been placed on the RASNZ website. Go to <http://www.rasnz.org.nz/minutes/minutes.htm> . You will find links to the minutes for 2008, 2009 and 2010. There are also links to the corresponding Annual Reports, that is the reports for the years 2007, 2008 and 2009.

5. TTOS5 to Unveil New Video Time Inserter

Attendees at the Fifth Trans-Tasman Occultation Symposium will be able to learn about a new video time inserter, which will have its debut at the Symposium.

This device was developed in Australia and has been long awaited for by Occultation Observers world wide since the and of production of the original Kiwi OSD. It provides a means of placing an accurate time reading on to a video of any event which requires precise timing information and will useful for other applications in addition to the observation and timing of lunar and minor planet occultations.

Dave Gault (NSW) has announced, on behalf of the International Occultation Timing Association (IOTA) and VideoTimers of California, that the device will be manufactured and offered for sale as a finished article - ready to time events. The device is now known as IOTA-VTI and as you can see from the IOTA bit of it's name, it is now a firmly a part of the organisation and it's on-going availability is assured.

A brief description and a kit of documentation about IOTA-VTI can be found at... http://users.tpg.com.au/users/daveg/IOTA-VTI/IOTA-VTI_ImminentLaunchV2.pdf as well as hyperlinks to YouTube videos.

Dave Gault says that at the moment, he is the point of contact for VideoTimers and is happy to answer enquiries sent to This email address is being protected from spambots. You need JavaScript enabled to view it..

IOTA-VTI will debut, in the flesh at the Fifth Trans-Tasman Symposium on Occultations (TTSO5), Napier, New Zealand - 26th and 27th May 2011. This symposium is being held in conjunction with the RASNZ Annual Conference being held in Napier 27-29th May. For further information please visit the RASNZ website conference pages at http://www.rasnz.org.nz/.

Adapted from an announcement from Dave Gault in the RASNZOccultations Yahoo group bulletin 6th May.

-- Pauline Loader

6. Bernard Mills

In a message to members of the Astronomical Society of Australia, Dr Dick Hunstead wrote:

It is with great sadness that I inform you of the passing of Emeritus Professor Bernard Mills on Monday [April 25th], after a short illness. Bernie was one of the pioneers of radio astronomy in Australia. After working on the development of radar systems with CSIRO Radiophysics during the war, he moved to the radio astronomy group in 1948 where he devised the innovative cross-type telescope design that bears his name. The Mills Cross carried out the first survey of the southern radio sky, cataloguing some 2200 radio sources and establishing Australia's credentials as a leader in the new science of radio astronomy.

In 1960 Bernie moved to the University of Sydney and began the design and construction of the one-mile aperture Molonglo Cross near Canberra, funded in large part by the US National Science Foundation. Its major task was to carry out a much deeper radio survey of the southern sky, completed in 1978 with the publication of the Molonglo Reference Catalogue. At that time Bernie was planning a further development of the telescope to turn the east-west arm into the Molonglo Observatory Synthesis Telescope. This change was realised and the telescope continued to produce world-class images for more than 20 years.

Bernie retired in 1985, but his legacy of challenging the conventional wisdom and technology of the day has been carried on by his former students and staff, culminating in the Square Kilometre Array Molonglo Prototype, a pathfinder for the future SKA. This instrument incorporates the mechanical structure and design of Mills' original telescope, reflecting his extraordinary intellect and capacity for innovation. His pioneering contributions were recognised in 2006 with the award of the Grote Reber Medal for Radio Astronomy at the International Astronomical Union meeting in Prague.

7. Gravity Probe B Confirms Einstein

Stanford and NASA researchers have confirmed two predictions of Albert Einstein's general theory of relativity, concluding one of the space agency's longest-running projects. The findings appear online in the journal Physical Review Letters.

Known as Gravity Probe B (GP-B), the experiment used four ultra-precise gyroscopes housed in a satellite to measure two aspects of Einstein's theory about gravity. The first is the geodetic effect, or the warping of space and time around a gravitational body. The second is frame- dragging, which is the amount a spinning object pulls space and time with it as it rotates.

After 52 years of conceiving, building, testing and waiting, the science satellite has determined both effects with unprecedented precision by pointing at a single star, IM Pegasi, while in a polar orbit around Earth. If gravity did not affect space and time, Gravity Probe B's gyroscopes would point in the same direction forever while in orbit. But in confirmation of Einstein's general theory of relativity, the gyroscopes experienced measurable, minute changes in the direction of their spin as they were pulled by Earth's gravity.

Much of the technology needed to test Einstein's theory had not yet been invented in 1959 when Leonard Schiff, head of Stanford's physics department, and George E. Pugh of the Defence Department independently proposed to observe the precession of a gyroscope in an Earth-orbiting satellite with respect to a distant star. Toward that end, Schiff teamed up with Stanford colleagues William Fairbank and Robert Cannon and subsequently, in 1962, recruited Everitt.

NASA came on board in 1963 with the initial funding to develop a relativity gyroscope experiment. Forty-one years later, the satellite was launched into orbit about 400 miles above Earth. The project was soon beset by problems and disappointment when an unexpected wobble in the gyroscopes changed their orientation and interfered with the data. It took years for a team of scientists to sift through the muddy data and salvage the information they needed.

Despite the setback, Gravity Probe B's decades of development led to groundbreaking technologies to control environmental disturbances on spacecraft, such as aerodynamic drag, magnetic fields and thermal variations. The mission's star tracker and gyroscopes were the most precise ever designed and produced.

Innovations enabled by GP-B have been used in the Global Positioning System, such as carrier-phase differential GPS, with its precision positioning that can allow an airplane to land unaided. Additional GP-B technologies were applied to NASA's Cosmic Background Explorer mission, which determined the universe's background radiation. That measurement is the underpinning of the Big Bang theory and led to the Nobel Prize for NASA's John Mather.

Over the course of its mission, GP-B advanced the frontiers of knowledge and provided a practical training ground for 100 doctoral students and 15 master's degree candidates at universities across the United States. Over 350 undergraduates and more than four dozen high school students also worked on the project, alongside leading scientists and aerospace engineers from industry and government.

For more see Gravity Probe B, Stanford: http://einstein.stanford.edu/index.html Gravity Probe B, NASA: http://www.nasa.gov/mission_pages/gpb/ Francis Everitt: http://www.stanford.edu/dept/physics/people/faculty/everitt_cw_francis.html

-- from a Stanford University press release forwarded by Karen Pollard.

8. Voyager Set to Enter Interstellar Space

More than 30 years after they left Earth, NASA's twin Voyager probes are now at the edge of the solar system and still working. With each passing day they are beaming back a message that, to scientists, is both unsettling and thrilling. The message is, "Expect the unexpected."

The adventure began in the late 1970s when the probes took advantage of a rare alignment of outer planets for an unprecedented Grand Tour. Voyager 1 visited Jupiter and Saturn, while Voyager 2 flew past Jupiter, Saturn, Uranus and Neptune. (Voyager 2 is still the only probe to visit Uranus and Neptune.)

Among the top discoveries from those encounters were the discovery of volcanoes on Jupiter's moon Io; evidence for an ocean beneath the icy surface of Europa; hints of methane rain on Saturn's moon Titan; the crazily-tipped magnetic poles of Uranus and Neptune; icy geysers on Neptune's moon Triton; planetary winds that blow faster and faster with increasing distance from the Sun.

"Each of these discoveries changed the way we thought of other worlds," says Ed Stone of the California Institute of Technology in Pasadena, Voyager Project Scientist since 1972. In 1980, Voyager 1 used the gravity of Saturn to fling itself slingshot-style out of the plane of the solar system. In 1989, Voyager 2 got a similar assist from Neptune. Both probes set sail into the void.

Sailing into the void sounds like a quiet time, but the discoveries have continued. Stone sets the stage by directing our attention to the kitchen sink. "Turn on the faucet," he instructs. "Where the water hits the sink, that's the Sun, and the thin sheet of water flowing radially away from that point is the solar wind. Note how the Sun 'blows a bubble' around itself."

There really is such a bubble. Researchers call it the "heliosphere" and it is gargantuan. Made of solar plasma and magnetic fields, the heliosphere is about three times wider than the orbit of Pluto. The Voyagers are trying to get out, but they're not there yet. To locate them, Stone peers back into the sink: "As the water [or solar wind] expands, it gets thinner and thinner, and it can't push as hard. Abruptly, a sluggish, turbulent ring forms. That outer ring is the heliosheath -- and that is where the Voyagers are now."

The heliosheath is a very strange place, filled with a magnetic froth no spacecraft has ever encountered before, echoing with low-frequency radio bursts heard only in the outer reaches of the solar system, so far from home that the Sun is a mere pinprick of light.

"In many ways, the heliosheath is not like our models predicted," says Stone. In June 2010, Voyager 1 beamed back a startling number: zero. That¹s the outward velocity of the solar wind where the probe is now. No one thinks the solar wind has completely stopped; it may have just turned a corner. But which way? Voyager 1 is trying to figure that out through a series of "weather vane" manoeuvres, in which the spacecraft turns itself in a different direction to track the local breeze.

No one knows exactly how many more miles the Voyagers must travel before they "pop free" into interstellar space. Most researchers believe, however, that the end is near. "The heliosheath is 3 to 4 billion miles [5 to 6.5 billion km] in thickness," estimates Stone. "That means we¹ll be out within five years or so."

There is plenty of power for the rest of the journey. Both Voyagers are energized by the radioactive decay of a Plutonium 238 heat source. This should keep critical subsystems running through at least 2020.

-- abridged from a NASA Jet Propulsion Laboratory press release forwarded by Karen Pollard.

9. Newly Discovered Tiny Companion to Earth

Astronomers have found that a recently discovered asteroid has been following the Earth in its motion around the Sun for at least the past 250,000 years. It may be intimately related to the origin of our planet.

The asteroid first caught the eye of the scientists, Apostolos "Tolis" Christou and David Asher of Armagh Observatory in Northern Ireland, two months after it was found by the WISE infrared survey satellite. "Its average distance from the Sun is identical to that of the Earth", says Dr. Christou, "but what really impressed me at the time was how Earth-like its orbit was". Most near-Earth asteroids -- NEAs for short -- have very eccentric, or egg-shaped, orbits that take the asteroid right through the inner solar system. But the new object, designated 2010 SO16, is different. Its orbit is almost circular so that it cannot come close to any other planet in the solar system except the Earth.

The researchers set out to investigate how stable this orbit is and how long the asteroid has occupied it. To do that, they first had to take into account the current uncertainty in the asteroid's orbit. Reducing the uncertainty usually requires tracking for months or years. The two scientists overcame that problem by creating virtual "clones" of the asteroid for every possible orbit that it could conceivably occupy. They then simulated the evolution of these clones under the gravity of the Sun and the planets for two million years into the past and in the future.

They found that all the clones remained in a so-called "horseshoe" state with respect to the Earth. In this configuration, an object mimics very closely the orbital motion of our planet around the Sun, but as seen from Earth it appears to slowly trace out a horseshoe shape in space. Asteroid 2010 SO16 takes 175 years to make the trip from one end of the horseshoe to the other. So while on the one hand its orbit is remarkably similar to Earth's, in fact "this asteroid is terraphobic", explains Tolis. "It keeps well away from the Earth. So well, in fact, that it has likely been in this orbit for several hundred thousand years, never coming closer to our planet than 50 times the distance to the Moon". This is where it is now, near the end of the horseshoe trailing the Earth.

Currently, three other horseshoe companions of the Earth are known to exist but, unlike 2010 SO16, these linger for a few thousand years at most before moving on to different orbits. Also, with an estimated diameter of 200-400 meters, 2010 SO16 is by far the largest of Earth¹s horseshoe asteroids.

Ultimately, Christou and Asher would like to know where it came from. It could be an ordinary asteroid coming from the Main Belt between Mars and Jupiter. In that case, the random gravitational pull of the different planets would be responsible for its present orbit; an unlikely proposition. It could also be a piece of the Moon that escaped the gravity of the Earth-Moon system and went into an independent orbit around the Sun. However, the very stability of its orbit means that there is currently no way to transport it from the Moon to where it is now. Finally, 2010 SO16 could represent leakage from a population of objects near the so-called triangular equilibrium points 60 degrees ahead of and behind the Earth in its orbit. Such a population has been postulated in the past but never observed as such objects are always near the Sun in the sky. If they do exist, they may represent relic material from the formation of Earth, Moon and the other inner planets 4.5 billion years ago.

The physical properties of the object can be studied from the ground, especially its colour. Colour can tell a lot about an object's origin. If it proves to be unique in some way, it may be worth sending a probe to study it up close, and perhaps bring back a sample for laboratory scrutiny.

For more see http://star.arm.ac.uk/highlights/2011/574.html and http://arxiv.org/abs/1104.0036 .

-- From a Royal Astronomical Society (http://www.ras.org.uk ) press release forwarded by Karen Pollard.

10. Amateurs Video Blinking Asteroid

Video imaging of newly discovered asteroid 2011 GP59 shows the object appearing to blink on and off about once every four minutes.

Amateur astronomers, including Nick James of Chelmsford, Essex, England, have captured video of the interesting object. James generated his video of GP59 on the night of Monday, April 11. The video, captured with an 11- inch (28 cm) Schmidt-Cassegrain telescope, is a compilation of 137 individual frames, each requiring 30 seconds of exposure. At the time, the asteroid was approximately 3,356,000 km distant. Since then, the space rock has become something of a darling of the amateur astronomy community, with many videos available. Here is one recent posting: http://www.youtube.com/watch?v=O7wsAZNr56E

"Usually, when we see an asteroid strobe on and off like that, it means that the body is elongated and we are viewing it broadside along its long axis first, and then on its narrow end as it rotates" said Don Yeomans, manager of NASA's Near-Earth Object Program Office at the Jet Propulsion Laboratory in Pasadena. "GP59 is approximately 50 meters long, and we think its period of rotation is about seven-and-a-half minutes. This makes the object's brightness change every four minutes or so."

2011 GP59 was discovered the night of April 8/9 by astronomers with the

Observatorio Astronomico de Mallorca in Andalusia, Spain. It made its closest approach to Earth on April 15 at a distance of 533,000 km, just beyond the Moon's orbit.

NASA detects, tracks and characterizes asteroids and comets passing close to Earth using both ground- and space-based telescopes. The Near-Earth Object Observations Program, commonly called "Spaceguard" discovers these objects, characterizes a subset of them, and plots their orbits to determine if any could be potentially hazardous to our planet.

More information about asteroids and near-Earth objects: http://www.jpl.nasa.gov/asteroidwatch

-- from a NASA JPL press release forwarded by Karen Pollard.

11. HST Images Colourful Galaxies

In celebration of the 21st anniversary of the Hubble Space Telescope¹s deployment into space, astronomers pointed Hubble at an especially photogenic group of interacting galaxies called Arp 273. The picture is found at http://hubblesite.org/news/2011/11

The picture shows a group of interacting galaxies called Arp 273. The larger of the spiral galaxies, known as UGC 1810, has a disc that is tidally distorted into a rose-like shape by the gravitational pull of the companion galaxy below it, known as UGC 1813. The swathe of blue jewels across the top is the combined light from clusters of intensely bright and hot young blue stars. These massive stars glow fiercely in ultraviolet light.

The smaller, nearly edge-on companion shows distinct signs of intense star formation at its nucleus, perhaps triggered by the encounter with the companion galaxy.

A series of uncommon spiral patterns in the large galaxy are a telltale sign of interaction. The large, outer arm appears partially as a ring, a feature that is seen when interacting galaxies actually pass through one another. This suggests that the smaller companion actually dived deeply, but off-centre, through UGC 1810. The inner set of spiral arms is highly warped out of the plane, with one of the arms going behind the bulge and coming back out the other side. How these two spiral patterns connect is still not precisely known.

A possible mini-spiral may be visible in the spiral arms of UGC 1810 to the upper right. It is noticeable how the outermost spiral arm changes character as it passes this third galaxy, from smooth with lots of old stars (reddish in colour) on one side, to clumpy and extremely blue on the other. The fairly regular spacing of the blue star-forming knots fits with what is seen in the spiral arms of other galaxies and can be predicted from the known instabilities in the gas contained within the arm.

The larger galaxy in the UGC 1810-UGC 1813 pair has a mass that is about five times that of the smaller galaxy. In unequal pairs such as this, the relatively rapid passage of a companion galaxy produces the lopsided or asymmetric structure in the main spiral. Also in such encounters, the starburst activity typically begins earlier in the minor galaxy than in the major galaxy. These effects could be due to the fact that the smaller galaxies have consumed less of the gas present in their nucleus, from which new stars are born.

Arp 273 lies in the constellation Andromeda and is roughly 300 million light-years away from Earth. The image shows a tenuous tidal bridge of material between the two galaxies that are separated by tens of thousands of light-years from each other.

The interaction was imaged on 17 December 2010, with Hubble¹s Wide Field Camera 3 (WFC3).

This Hubble image is a composite of data taken with three separate filters on WFC3 that allow a broad range of wavelengths covering the ultraviolet, blue, and red portions of the spectrum.

-- from a European Space Agency press release forwarded by Karen Pollard.

12. 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

13. Kingdon-Tomlinson Fund

The RASNZ is responsible for recommending to the trustees of the Kingdon Tomlinson Fund that grants be made for astronomical projects. The grants may be to any person or persons, or organisations, requiring funding for any projects or ventures that promote the progress of astronomy in New Zealand. Full details are set down in the RASNZ By-Laws, Section J.

For an application form contact the RASNZ 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

14. 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. For overseas rates please check with the membership secretary, This email address is being protected from spambots. You need JavaScript enabled to view it..

15. Quotes

 

"Wherever they burn books they will also, in the end, burn human beings." -- Heinrich Heine.

"What we think, or what we know, or what we believe is, in the end, of little consequence. The only consequence is what we do." -- John Ruskin.

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


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