RASNZ Electronic Newsletter August 2017

The RASNZ Email newsletter is distributed by email on or near the 20th of each month. If you would like to be on the circulation list This email address is being protected from spambots. You need JavaScript enabled to view it. for a copy. The latest issue is below.

Email Newsletter Number 200

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.


1. Harry Williams Astrophotography Competition
2. Third International Starlight Festival, 13-15 October
3. The Solar System in September
4. (3122) Florence Fly-By
5. Safe Solar Eclipse Viewing
6. Auckland Astronomical Society on YouTube
7. Variable Star News
8. Asteroid Moon Discovered By Amateur Astronomers
9. Cassini's Last Looks at Saturn
10. Brown Dwarfs Common?
11. Life-Building Chemical Found Around Young Stars
12. Mt John History Price Reduced
13. How to Join the RASNZ
14. Gifford-Eiby Lecture Fund

1. Harry Williams Astrophotography Competition

Calling all Astrophotographers, the 2017 Harry Williams Astrophotography Competition is now open for entries, this year our judge is world-renowned planetary photographer Damian Peach, in 2010, Damian became the only Briton to win the prestigious Astronomy Photographer of the Year Award for his composite photograph of Jupiter's moons, Ganymede and Io, orbiting the stormy surface of the Gas Giant.

Damian is arguably the world's most well-known planetary photographer, his high resolution images of the planets have been compared in quality to the kind of images captured by orbiting spacecraft! So we are truly lucky to have Damian on board as our judge for this year's competition.

As in previous years we are lucky to have Australian Sky & Telescope on board as sponsors of both the Solar System category and the Miscellaneous / Artistic category, the winners of these categories will receive a one year subscription to the magazine as well as the usual cash prize. More sponsors to be announced soon.

The competition cut-off date is the 31st of August and the competition awards will be announced at the annual Burbidge dinner which is the Society's premier annual event, keep an eye out on the society website for details on the forthcoming Burbidge dinner.

The competition rules and entry forms can be found on the Auckland Astronomical Society website http://www.astronomy.org.nz/new/public/default.aspx

-- From the above website

2. Third International Starlight Festival, 13-15 October

The Third International Starlight Festival will be held at the Hermitage, Mt Cook over three days in 2017, 13-15 October.

The Festival will celebrate the Aoraki Mackenzie International Dark Sky Reserve (www.darkskyreserve.org.nz) whose mission is to encourage and protect dark skies free of light pollution in the Mackenzie, and to promote star gazing and astro-tourism. We do this by organizing a Starlight Festival every second year for the benefit of the public and international tourists. Astro-tourism in the Mackenzie at Tekapo and Mt Cook is now one of New Zealand´s biggest tourist attractions, with about 200,000 people coming to Tekapo annually, many from Asia and Europe, to see the stars.

The 2017 Festival will be our third, after very successful events in 2013 in Tekapo and 2015 at Twizel. The Festival will be a mixture of events including lectures, workshops, exhibitions, videos and documentaries, planetarium shows and of course, star-gazing. We have engaged three world-class speakers to come to Mt Cook for the Festival. They are:

o Dr Natalie Batalha NASA Ames space scientist, Moffett Field (near San Francisco), California. (Time Magazine in April 2017 named her as one of the 100 most influential people on the planet). She will talk about `A Planet for Goldilocks´ and the search for habitable Earth-like planets o Kevin Govender, Director of the Office of Astronomy for Development of the International Astronomical Union, based in Cape Town, South Africa. He will talk about `Astronomy for Humankind´. o Sze-leung Cheung, Director of the Office of Astronomy Outreach of the International Astronomical Union, based in Tokyo, Japan. He will talk about `The threat of LEDs to astronomy and how to build a dark-sky-friendly future´.

All three are outstanding speakers, and Sze-leung Cheung is fluent in Chinese as well as English, so can give his talk in both languages to attract overseas tourists.

More details on the Third Starlight Festival and our keynote speakers are at www.starlightfestival.org.nz. On-line ticket sales will be available from mid-July. The website also has all accommodation options in and near Mt Cook.

Mark Gee from Wellington will show some of his stunning night-sky time-lapse animations and on the morning of Oct 14 will conduct an astro-photography workshop for everyone wanting to learn these techniques. Steve Chadwick from Palmerston North will show his amazing night sky animations and photography, as will also the renowned Fairlie and Tekapo astrophotographer, Fraser Gunn.

There is also an astro-photography exhibition with nine of New Zealand´s top astro-photographers exhibiting their images. The Festival features videos, exhibitions, workshops, planetarium shows and stargazing (at the new Mt Cook Observatory) over three days, 13-15 October.

-- John Hearnshaw, Chair, Aoraki Mackenzie International Dark Sky Reserve Board.

3. The Solar System in September

NZDT starts at 2am on the morning of September 24 when clocks should be advanced by 1 hour, bringing NZ time to UT + 13 hours. Dates and times shown are NZST (UT + 12 hours) until September 23 and then NZDT for the rest of the month, unless otherwise stated. The southern spring equinox is on September 23, NZ time, with the Sun crossing the celestial equator at about 8am.

Sunrise, Sunset and Twilight Times in September

Times are for Wellington. They will vary by a few minutes elsewhere in NZ.

                   September  1  NZST             September 30  NZDT
       SUN: rise: 6.43am,  set: 5.58pm    rise:  6.54am,  set: 7.27pm
Twilights     morning       evening          morning       evening
Civil:    starts: 6.18am, ends: 6.24pm   starts: 6.29am, ends: 7.53pm
Nautical: starts: 5.46am, ends: 6.56pm   starts: 5.57am, ends: 8.26pm
Astro:    starts: 5.15am, ends: 7.28pm   starts: 5.23am, ends: 8.59pm

September Phases of the Moon (times NZST, as shown by GUIDE)

          Full moon:     September  6 at  7.03 pm (07:03 UT)
  Last quarter   September 13 at  6.25 pm (06:25 UT)
  New moon:      September 20 at  5.30 pm (05:30 UT)
  First quarter: September 28 at  3.54 pm (02:54 UT)

The Planets in September 2017

The three terrestrial planets, Mercury, Venus and Mars, are all morning objects rising shortly before the Sun. Venus should be observable, especially early in the month. Mercury and Mars are not likely to be observable at any time.

VENUS starts the month rising nearly an hour and a half before the Sun. Half an hour before sunrise it will be some 9° up so easily visible as a low brilliant object. It will be well round to the north from east. The planet gets closer to the Sun as September progresses, so that by the 30th it will rise 50 minutes before the Sun. As a result, Venus will be then very low shortly before the Sun rises, and not as far to the north of east as at the beginning of the month.

In the middle of the month the three terrestrial planets will form quite a tight group in Leo fairly close to Regulus. On the 18th they are joined by the Moon. In a period of just under 24 hours, the Moon will occult Venus, Regulus, Mars and Mercury as seen from some part of the Earth. The Venus event is visible, as a daytime event, from all of Australia and New Zealand. At Wellington the time of disappearance is about 1:27 pm and the reappearance at 2:40 pm. The moon will be only a 6% lit crescent about 28° from the Sun. Binoculars are likely to show up the event, but the very thin crescent moon May be difficult to find. [Be sure to use binoculars from a shaded location so not to accidentally look at the Sun. - Ed.]

JUPITER is visible in the early evening during September. It sets three and a half hours later than the Sun on the 1st, about 100 minutes later on the 30th so by then will be a low object to the west following sunset. Jupiter is in Virgo, close to Spica. At their closest on the 12th, the 1st magnitude star will be 3° to the left of the planet. On the 22nd, the crescent moon will join the pair, when it will be just over 4° to the lower right of Jupiter. By then it would be best to be looking by 7pm or soon after. An hour later the three will be very low.

SATURN is visible all evening during September, although it will set about 1.40 am NZDT on the 30th. Saturn will be in Ophiuchus. Its encounter with the moon will be on the 27th, the moon being a day short of first quarter, about 5° to the right of Saturn mid evening.

OUTER PLANETS URANUS rises just before 10pm NZST on the 1st and close to 9 pm on the 30th. The planet is in Pisces at magnitude 5.7 throughout the month.

NEPTUNE rises close to the time of sunset on September 1. By the 30th it will rise just after 5pm NZDT over 2 hours before the Sun sets. So it will then be well placed for viewing in the evening sky. The planet is in Aquarius at magnitude 7.8.

PLUTO, magnitude 14.4, remains in Sagittarius. It will be just under a degree from the 2.9 magnitude star pi Sgr.

MINOR PLANETS (1) CERES, a morning object starts the month at magnitude 9.0 in Gemini. On the 18th it will cross into Cancer brightening slightly during the month to magnitude 8.8.

(2) PALLAS is in Eridanus rising at 10.20 pm on the 1st. During September it brightens from magnitude 9.0 to 8.5.

(7) IRIS is in Aries throughout September, brightening from magnitude 8.5 to 7.7 during the month. It rises at 11:12 pm on the 1st and 10.33 pm on the 30th. It is quite close to Hamal, alpha Ari magnitude 2.0. Their separation is 2.1° on the 1st, increasing to 3.7° on the 24th after which Iris starts moving back towards Hamal.

(89) JULIA is in Pegasus all month. It is at opposition at the beginning of September. For a few nights it will reach magnitude 9.0. On the 2nd it will form a near equilateral triangle with the stars zeta Peg (mag 3.4) and xi Peg (mag 4.2). Julia´s motion will take it past zeta, the two being 8 arc-minutes apart on the 8th. By the end of September Julia will have faded to magnitude 9.4.

Near Earth Object (3122) FLORENCE rapidly fades in early September as its distance from the Earth increases. On the 1st it will be at mag 8.9, 7 million km from the Earth and moving at about 24 arc-minutes per hour. The next two nights finds it in Delphinus, magnitudes 9.1 and 9.3 respectively. It is in Vulpecula at magnitude 9.6 on the 4th and in Cygnus at 9.9 on the 5th. By then Florence will be 8.4 million km away with an apparent speed 17 arc minutes per hour. [See below for a daily ephemeris for Florence.]

-- Brian Loader

4. (3122) Florence Fly-By

Asteroid (3122) Florence passes 0.047 AU, 7 million km, from Earth on September 1. At that time it will be moving across the sky at 24'/hour, a full-moon diameter in 80 minutes. In a telescope it will appear as a ninth magnitude star.

A daily ephemeris is below. To get ephemerides for other times go to the Minor Planet Center's website at http://www.minorplanetcenter.net/iau/MPEph/MPEph.html Enter 3122 in the Object window. The format for the ephemeris start time is YYYY MM DD HHMM in UT. Observatory Code 485 (Carter Observatory) is close enough for all New Zealand.

(3122) Florence Positions at 12h UT = midnight NZST in August-September.

      R.A.(2000)Dec.                 R.A.(2000)Dec.
Date h  m  s    °  '  Mag.     Date h  m  s    °  '  Mag.
16  23 00 00  -61 27  11.7     26  21 52 45  -40 31   9.6
17  22 54 54  -60 32  11.5     27  21 44 14  -35 40   9.4
18  22 49 26  -59 29  11.4     28  21 35 29  -29 54   9.1
19  22 43 35  -58 15  11.2     29  21 26 31  -23 07   8.8
20  22 37 23  -56 49  11.0     30  21 17 23  -15 19   8.7
21  22 30 48  -55 07  10.8     31  21 08 07  -06 42   8.7
22  22 23 52  -53 08  10.6      1  20 58 46  +02 25   8.8
23  22 16 34  -50 45  10.4      2  20 49 21  +11 31   9.0
24  22 08 57  -47 56  10.2      3  20 39 55  +20 07   9.3
25  22 01 00  -44 34   9.9      4  20 30 31  +27 52   9.6

5. Safe Solar Eclipse Viewing

On August 21, US date, a total solar eclipse track crosses the United States. Nothing will be seen from New Zealand. However, the American Astronomical Society (AAS) has put out a warning about eclipse viewers that might be a useful reference for anyone wanting to look at the sun by eye or planning to view a solar eclipse.

On August 21, US date, a total solar eclipse track crosses the United States. The partial eclipse phase will be seen from all North America and the northern part of South America. Nothing will be seen from New Zealand.

The AAS's page on safe eclipse viewing is at https://eclipse.aas.org/eye-safety

The AAS's Reputable Vendors of Solar Filters & Viewers page is at https://eclipse.aas.org/resources/solar-filters

An article on Sky & Telescope's webpage warns of unsafe eclipse viewers that are being hawked around. Some paragraphs from it:

How can you tell if your "eclipse glasses" or handheld solar viewers are safe? It is no longer sufficient to look for the logo of the International Organization for Standardization (ISO) and a label indicating that the product meets the ISO 12312-2 international safety standard for filters for direct viewing of the Sun´s bright face. Why not? Because it now appears that some companies are printing the ISO logo and certification label on fake eclipse glasses and handheld solar viewers made with materials that do not block enough of the Sun´s ultraviolet, visible, and infrared radiation to make them truly safe. Some sellers are even displaying fake test results on their websites to support their bogus claim of compliance with the ISO safety standard.

Given this unfortunate situation, the only way you can be sure your solar viewer is safe is to verify that it comes from a reputable manufacturer or one of their authorized dealers. The AAS Solar Eclipse Task Force has been working diligently to compile a list of such vendors, now posted on its Reputable Vendors of Solar Filters & Viewers page. See the link above.

How can you tell if your solar viewer is NOT safe? The only thing you can see through a safe solar filter from a reputable vendor is the Sun itself. If you can see ordinary household lights through your eclipse glasses or handheld viewer, it´s no good. Safe solar filters produce a view of the Sun that is comfortably bright (like the full Moon), in focus, and surrounded by black sky. If you glance at the Sun through your solar filter and find it uncomfortably bright, out of focus, and surrounded by a murky haze, it´s no good.

Some eclipse glasses and solar viewers are printed with warnings stating that you shouldn´t look through them for more than 3 minutes at a time and that you should discard them if they are more than 3 years old. Such warnings are outdated and do not apply to eclipse viewers compliant with the ISO 12312-2 international safety standard, which was adopted in 2015. If your eclipse glasses or viewers are relatively new and are ISO 12312-2 compliant, you May look at the uneclipsed or partially eclipsed Sun through them for as long as you wish. Furthermore, if the filters aren´t scratched, punctured, or torn, you May reuse them indefinitely.

What about welding filters? The only ones that are safe for direct viewing of the Sun with your eyes are those of Shade 12, 13, or 14. These are much darker than the filters used for most kinds of welding. If you have an old welder´s helmet and are thinking of using it to view the Sun, make sure you know the filter´s shade number. If it´s less than 12 (and it probably is), don´t even think about using it to look at the Sun. Many people find the Sun too bright even in a Shade 12 filter, and some find the Sun too dim in a Shade 14 filter -- but Shade 13 filters are uncommon and can be hard to find. The AAS´s Reputable Vendors of Solar Filters & Viewers page doesn´t list any suppliers of welder´s filters, only suppliers of special-purpose filters made for viewing the Sun.

For much more see http://www.skyandtelescope.com/astronomy-news/aas-offers-updated-advice-for-safely-viewing-the-August-21st-solar-eclipse-across-america/AAS´s Advice for Safe Solar-Eclipse Viewing

6. Auckland Astronomical Society on YouTube

The Auckland Astronomical Society is now broadcasting many of its meetings and speakers online through its YouTube channel. You can choose to watch the events live or at a later time, perfect if you cannot make a meeting or would like to see the talk again.

You can subscribe to the YouTube channel at: https://www.youtube.com/channel/UC4W5_RJtWZBceOteC-8PTIA

-- Note from Simon Lowther.

7. Variable Star News

The Variable Stars South Newsletter 2017-3 (July) is now available for download from the website https://www.variablestarssouth.org/ Items of interest:

New Director of VSS Stan Walker has announced that he is retiring as Director of the RASNZ Section Variable Stars South. The new Director is Mark Blackford who has been a pioneer of making DSLR imaging quantitative; he is well known for his papers and manuals on DSLR photometry. Mark contributed to the RASNZ Whakatane Conference and associated Variable Star Symposium in 2014 and also attended the Tekapo Conference. Stan´s comments on signing off and some of Mark´s thoughts on directions for VSS are given in the July issue of the VSS Newsletter. See it in the VSS July Newsletter.

Large Telescope Installed Stephen Hovell has an observatory, Pukemanu, 11 km south-east of Kaitaia. For his new observatory he planned to have a Dobsonian with a 24" mirror but has ended up with a 28" f/3.3 scope. The mirror was manufactured by Lockwood Custom Optics in USA and the telescope constructed and installed by SDM (stands for Size does matter) run by Peter Read who is located in Bunbartha, Victoria, Australia. The telescope arrived in March and is now safely installed. For a full description of the components of the system see the article in the July VSS Newsletter.

Stephen is a dedicated visual observer and is pleased with the reach of his new telescope with which on most nights he can observe down to magnitude 16.5 or 17.0, allowing him to follow R Coronae Borealis and other variables further through their deep minima light curves.

Stars Types Featured in July Issue Mati Morel´s investigation of the identity of 142 variable stars in the Innes catalogue developed in 1914, 1915 & 1917. Stan Walker has an article on the humps of R Tel and another on extending the Double Maxima Mira project to other, moderate mass, pulsating variables. It includes a description of methods of observing and reporting. Tom Richards describes the O-C (observed -calculated) method for calculating changes in the period of eclipsing binaries which are used in astrophysical studies of these stars and invites observers to contribute to this programme.

-- Alan Baldwin

8. Asteroid Moon Discovered By Amateur Astronomers

A team of amateur observers, some using just 75 mm telescopes, have found that the main-belt asteroid (113) Amalthea probably has a small companion.

Each year, amateur astronomers get worldwide predictions for hundreds of events during which a distant asteroid briefly occults (hides) a star. But some of these occultations - like the one involving asteroid 113 Amalthea last March 14th - are anticipated more eagerly than others.

That date has been circled on Paul Maley's calendar for about 8 months. A retired NASA staffer and a key member of the International Occultation Timing Association, last year Maley started enlisting amateur observers in Texas to observe the occultation of a 10th-magnitude star by 13th-magnitude Amalthea. And all that planning paid off, because the observing team has discovered that this asteroid probably has a small satellite.

It's a robust "probably." As detailed in the IAU's Electronic Telegram 4413, issued on July 12th, a "fence" of 10 observing sites spread across the occultation's predicted path yielded seven positive occultations and three "misses." One of those misses, by Sam Insana in Gila Bend, Arizona, fell between five positive occultation tracks to his north and two to his south.

In other words, Insana was fortuitously positioned in the gap between Amalthea and its moon. Two short breaks were recorded by Dave Eisfeldt and Dick Campbell (Central Texas Astronomical Society) which corresponded to interruptions of the star's light by the moon. "This is the first time that two chords have been observed across a previously unknown minor-planet satellite," comments Daniel W. E. Green in the announcement. There were five other members of the team, one of whom set up four robotic cameras for the event.

Not to be confused with Jupiter's small satellite of the same name, Amalthea orbits the Sun every 3.66 years in a reasonably circular orbit that averages 2.37 astronomical units (324 million km) from the Sun with an inclination of 5°. Discovered in 1871, it's about 46 km across and has a rocky "S type" surface spectrum, which is typical for the bodies that populate the inner main belt. Based on the lengths of each occultation record and how they line up in the plot, Amalthea must have a distinctly elongated shape.

The size of the satellite isn't known, though typically such companions are much smaller than their hosts. According to the definitive compilation by Wm. Robert Johnston, the census of asteroids with moons now includes 133 main-belt asteroids (8 with two each), 22 Mars crossing asteroids (1 with two), and 62 near-Earth asteroids (2 with two each). Looking farther outward, Johnston's listing includes 4 of Jupiter's Trojans and 81 trans-Neptunian objects.

Confirmation of the discovery might not have to wait long. Although no one had previously observed a stellar occultation by Amalthea, four are predicted for next year - including an April 14th event with a track that crosses the north-central U.S.

-- From an article by Kelly Beatty on Sky & Telescope's webpage at http://www.skyandtelescope.com/astronomy-news/amateur-observers-discover-asteroid-moon/

9. Cassini's Last Looks at Saturn

The ringed planet seems to be hanging on to at least some of its secrets right up until the very end.

The NASA-ESA-ASI robotic spacecraft Cassini is now in the midst of a series of dramatic weekly Grand Finale dives through the gap between Saturn and its ring system. This follows a series of wider Ring Grazing Orbits spanning late 2016 into earlier this year, and will climax with the end of the mission itself in September.

Cassini is now in the 16th of a total of 22 weekly orbits, coming as close as 3000 km to the planet's cloud tops. This allows the mission to not only examine the magnetic field of the planet close up, but also allows Cassini a chance to sample the upper atmosphere of the planet itself.

These final orbits are a bit of a risk, as the spacecraft must thread its way through the ring plane at 124,000 kph (34 km/s). This elevated risk is one reason that researchers have held off on the exploration of Saturn close-up until now.

One of the strangest recent findings from Cassini is what it didn't find: much of a discernible difference in tilt between Saturn's rotational axis and its magnetic field. In other planets, this tilt sustains the dynamos that emanate from liquid metal cores. Think of Earth, where liquid iron in its outer core generates our protective magnetic field - and a magnetic pole offset from Earth's true, rotational pole.

Cassini's magnetometer has found that Saturn's magnetic pole - in this case, generated by liquid metallic hydrogen in its core - is remarkably well aligned with the planet's rotational axis, down to less than 0.06 degrees. This finding flies in the face of how we think planetary magnetic fields are generated, suggesting that we don't understand Saturn's internal structure as well as we thought we did.

The surprisingly good alignment also masks the true length of Saturn's day. While we see the planet's cloud tops spinning once every 10 hours, 14 minutes near the planet's equator, a gaseous planet doesn't all rotate at the same rate so its rotation changes at the poles. A discernible tilt in the magnetic field would make the field wobble, betraying the core's true rotational speed. Since scientists haven't been able to measure the wobble, the length of Saturn's day remains a mystery.

On the first plunge through the ring plane, Cassini went "dish first," using its large radio antenna to protect the bulk of the spacecraft while a few instruments made tentative peeks out around the edges to "sniff" the local environment. But as researchers discovered the gap between the planet and the rings is - at least where Cassini sampled it - surprisingly devoid of debris, engineers relaxed constraints somewhat on subsequent passages, bringing other instruments to bear. Cassini has since used its Ion and Neutral Mass Spectrometer (INMS) to sample the tenuous exosphere of Saturn's atmosphere and its Cosmic Dust Analyser (CDA) to sample the few ring particles obtained on each pass.

What's next? Cassini will dive deeper still on final passes and the INMS is expected to get better atmospheric samples on each pass. And of course, we've getting some thrilling up close images of Saturn itself, with more to come.

Launched two decades ago in 1997, the Cassini mission promises a thrill ride to the very last moment, just over one month away. Cassini is on a ballistic date with destiny, meaning that even if the spacecraft were to fall silent, destruction via atmospheric entry on September 15th is assured. But the science results will continue to pay off for years to come. Not bad for a spacecraft launched last century.

-- From an article, dated July 31, by David Dickinson on Sky & Telescope's website at http://www.skyandtelescope.com/astronomy-news/saturn-surprises-cassini-right-up-until-the-end/

10. Brown Dwarfs Common?

A new study of a nearby cluster of newly formed stars reveals that brown dwarfs might rival stars in the Milky Way in number, with one brown dwarf for every two bona fide stars.

Since their discovery in 1995, brown dwarfs, so-called "failed stars", have fascinated astronomers. At less than 8% the mass of the Sun, brown dwarfs fail to ignite fusion in their core. Glowing initially with the heat of their formation, they slowly cool over billions of years like dim red embers. Due to their intrinsic faintness, most of the known brown dwarfs are relatively close to the Sun, within a few thousand light years. But there are brown dwarfs beyond the grasps of our telescopes - we just don´t know exactly how many.

Now, an international team of astronomers, led by Koraljka Muzíc (University of Diego Portales, Chile, and University of Lisbon, Portugal), has estimated that the Milky Way contains many more brown dwarfs than we once thought. The article is available on the astrophysics arXiv.

Muzíc and collaborators trained the European Southern Observatory's Very Large Telescope (VLT) on the RCW 38 star-forming cluster 5,500 light-years from the Sun. Most of the Milky Way´s stars began in similar clusters over billions of years. Such clusters are still valued for studying how stars form and how environment - the physical properties of the gas and dust in the natal cloud - can influence the distribution of the stars that form in the cluster. Even small cluster-to-cluster variations can have a big impact on the final stellar population of the Galaxy.

RCW 38 is massive, as star clusters go, and vigorously forming new stars. Muzíc's team imaged deep into the cluster, identifying bright massive stars and dim brown dwarfs within the same data. Using the VLT, the team was able to capture brown dwarfs with masses down to about 2% that of the Sun.

The team found more brown dwarfs than expected from previous cluster studies. That suggests that brown dwarfs May be more common than previously thought. In this cluster, there´s approximately one brown dwarf for every two bona fide stars. When applied to the rest of the galaxy (which contains some 200 billion stars), that adds up to about 100 billion brown dwarfs, dimly gliding along in the Milky Way.

This result will be directly tested on two fronts. First, studies will continue to refine the brown dwarf populations within other star clusters, such as the Orion Nebula Cluster. Next, large upcoming surveys such as WFIRST and LSST will image the galactic field to faint brightnesses, enabling astronomers to extend the local brown dwarf census. These faint almost-stars May prove to be just as ubiquitous as their stellar siblings.

-- From an article by John Bochanski on Sky & Telescope's webpage at http://www.skyandtelescope.com/astronomy-news/100-billion-brown-dwarfs-milky-way/

11. Life-Building Chemical Found Around Young Stars

ALMA has observed stars like the Sun at a very early stage in their formation and found traces of methyl isocyanate - a chemical building block of life. This is the first ever detection of this prebiotic molecule towards solar-type protostars, the sort from which our Solar System evolved. The discovery could help astronomers understand how life arose on Earth.

Two teams of astronomers used the Atacama Large Millimeter/ submillimeter Array (ALMA) in Chile to detect the prebiotic complex organic molecule methyl isocyanate in the multiple star system IRAS 16293-2422. A complex organic molecule is defined in astro-chemistry as consisting of six or more atoms, where at least one of the atoms is carbon. Methyl isocyanate contains carbon, hydrogen, nitrogen and oxygen atoms in the chemical configuration CH3NCO. This family of organic molecules is involved in the synthesis of peptides and amino acids, which, in the form of proteins, are the biological basis for life as we know it.

IRAS 16293-2422 was previously studied by ALMA in 2012 and found to contain molecules of the simple sugar glycolaldehyde, another ingredient for life.

ALMA´s capabilities allowed both teams to observe the molecule at several different and characteristic wavelengths across the radio spectrum. They found the unique chemical fingerprints located in the warm, dense inner regions of the cocoon of dust and gas surrounding young stars in their earliest stages of evolution. Each team identified and isolated the signatures of methyl isocyanate. They then followed this up with computer chemical modelling and laboratory experiments to refine our understanding of the molecule´s origin.

IRAS 16293-2422 is a multiple system of very young stars, around 400 light-years away in a large star-forming region called Rho Ophiuchi in the constellation of Ophiuchus (The Serpent Bearer). The new results from ALMA show that methyl isocyanate gas surrounds each of these young stars.

Earth and the other planets in our Solar System formed from the material left over after the formation of the Sun. Studying solar-type protostars can therefore open a window to the past for astronomers and allow them to observe conditions similar to those that led to the formation of our Solar System over 4.5 billion years ago.

The detection supports laboratory results that show that methyl isocyanate can be produced on icy particles under very cold conditions that are similar to those in interstellar space This implies that this molecule - and thus the basis for peptide bonds - is indeed likely to be present near most new young solar-type stars.

-- From European Southern Observatory press release eso1718 forwarded by Karen Pollard. See the original with images and links at https://www.eso.org/public/unitedkingdom/news/eso1718/

12. Mt John History Price Reduced

The Mt John history 'Mt John - The First 50 Years', a celebration of half a century of optical astronomy at the University of Canterbury by John Hearnshaw and Alan Gilmore, published in March 2015 is now selling for $20. It was $60. For details see http://www.cup.canterbury.ac.nz/catalogue/mt_john.shtml

13. How to Join the RASNZ

RASNZ membership is open to all individuals with an interest in astronomy in New Zealand. Information about the society and its objects can be found at http://rasnz.org.nz/rasnz/membership-benefits A membership form can be either obtained from This email address is being protected from spambots. You need JavaScript enabled to view it. or by completing the online application form found at http://rasnz.org.nz/rasnz/membership-application Basic membership for the 2017 year starts at $40 for an ordinary member, which includes an electronic subscription to our journal 'Southern Stars'.

14. 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., Nichola van der Aa, 32A Louvain Street, Whakatane 3120.


"The most dangerous person is the one who listens, thinks and observes." -- Bruce Lee.

"Meetings are indispensable when you don't want to do anything." -- J.K. Galbraith.

"What I write is smarter than I am - because I can rewrite it." -- Susan Sontag.

Newsletter editor:

Alan Gilmore Phone: 03 680 6817
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