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ASTROSAT: India's First Dedicated Multi-Wavelength Space Wellington Astronomical Society March 2017 Volume 47 Issue 2 WWW.WAS.ORG.NZ, ISSN 01147706 - PRINT, ISSN 2230-5912 ONLINE The next WAS meeting will be held on Wednesday 1st of March 2017 at 7:30 pm at Carter Observatory, Upland Rd, Kelburn, Wellington ASTROSAT: India’s first dedicated multi-wavelength space observatory Jibu Stephen With the multi-wavelength astronomy mission ASTROSAT, India became the fifth nation to have an observatory in Inside this issue: space. The five instruments on-board the satellite would Wellington Astronomical Society enable simultaneous observations in optical, ultraviolet and 3 X-ray bands. The mission aims to study high energy process- March 2017 Events es in binary star systems containing neutron stars and black holes, to estimate magnetic fields of neutron stars and to Planetary Accretion 4 study star birth regions and high energy processes in star Movie: Hidden Figures 4 systems lying beyond our galaxy. Early results from the Ultra -Violet Imaging Telescope reveal a hot companion star asso- Solar Eclipse Provides Coronal ciated with a blue straggler star in open cluster NGC-188. 5 Glimpse 2017 North American Eclipse Tour 6 Jibu Stephen has a Ph. D. in Physics (Condensed Matter) from Victoria University of Wellington. He worked at the L2 Puppis - Is the puzzle solved? 7 Indian Institute of Astrophysics before moving to New Zea- Introducing astrometry.net 8 land and was part of the Ultraviolet Imaging Telescope team. Occultations for March 2017 13 March Night Sky Chart 17 The Night Sky in March 18 Page 2 VOLUME 47 ISSUE 2 2016 — 2017 SUBSCRIPTIONS DUE The new subscription year began in Adult/Waged: $ 50.00 Box 3181, Wellington 6140 September, so WAS looks forward to Student/Unwaged: $ 30.00 Direct Deposit or Internet Banking - receiving your subscription renewal. use Acc No: 03-0502-0508656-00, Family: $ 70.00 Renewal forms can be found on the please include reference so WAS knows website, but a summary follows: Payment methods: who is making the payment Subscription for Newsletter by Cheque - make out to Wellington As- Cash - please bring exact amount to Email 2016-2017 tronomical Society Inc, and mail to PO meeting WAS COUNCIL MEMBERS AND CONTACTS Council Members Website : John Homes & Peter Woods [email protected] The following members were elected to Council at the Nov 2016 AGM Council President: Antony Gomez [email protected] / 021_253_4979 Andrew Fuller Edward Wilcock Vice President: Duncan Hall [email protected] Frank Andrews Janine Bidmead Secretary/Telescope custodian: Chris Monigatti [email protected] / 021_890_222 Murray Forbes Peter Woods Treasurer: John Homes Sarah Taylor Newsletter Editor: Gerard Coyle Postal Address: Wellington Astronom- [email protected] ical Society, PO Box 3181, Wellington 6140, New Zealand Membership Secretary: Janine Bidmead [email protected] WAS ON FACEBOOK Our Facebook page “Wellington Astro- Remember you will need to interact anyone to join by request. The public nomical Society” is now operational. occasionally with the page by liking or group is open for discussion or postings You can search for it on Facebook or commenting on postings, or indicating on astronomical news. The WAS Astro- click on this link https:// whether you are coming to an event. photography Group https:// www.facebook.com/ Otherwise Facebook will, after a time, www.facebook.com/ WellingtonAstronomicalSociety/. stop sending you new postings. So keep groups/1684738758511214/ is for those visiting the page as there are a number interested in astrophotography. It If you are a Facebook user, please use of Society events coming up in the next serves as a place to notify others of the page to receive up-to-date notifica- few months. astrophotography gatherings at short tions of our Society’s events and news. notice and to display images captured This is the easiest way to keep informed We also have Facebook group “WAS – by members. as to what is going on in the Society, as Wellington Astronomical Society” well as keeping up with astronomical https://www.facebook.com/ news. groups/96304353012/ which is open for Page 3 VOLUME 47 ISSUE 2 Wellington Astronomical Society March 2017 Events WAS March Meeting March’s talk is given by Jibu Stephen. He will be taking about ASTROSAT: India’s first dedicated multi-wavelength space observatory. With the multi-wavelength astronomy mission ASTROSAT, India became the fifth nation to have an observatory in space. The five instruments on-board the satellite enable simultaneous ob- servations in optical, ultraviolet and X- ray bands. The mission aims to study high energy processes in binary star systems containing neutron stars and black holes, to estimate magnetic fields of neutron stars and to study star birth regions and high energy processes in Jibu Stephen has a Ph. D. in Physics Telescope team. star systems lying beyond our galaxy. (Condensed Matter) from Victoria Early results from the Ultra-Violet Im- Date: Wednesday, 1st March University of Wellington. He worked aging Telescope reveal a hot compan- at the Indian Institute of Astrophysics Time: 7:30 pm ion star associated with a blue strag- before moving to New Zealand and gler star in open cluster NGC-188. Venue: Space Place (at Carter Obser- was part of the Ultraviolet Imaging vatory) WAS Society Observing Evening Come along and see the many won- lar globular cluster 47 Tucanae and the Date: Saturday 4th March derful objects, star clusters, galaxies, Tarantula Nebula in the Large Magel- Time: 7:00 pm dying stars and nebulae around and lanic Cloud (LMC). Jupiter rises around near the Southern Cross, the spectacu- 10pm Venue: Tawa College Astronomy Club Night A short presentation and observing the Date: Thursday 9th March Venue: Hutt International Boys night sky. School Time: 7:00pm, Astronomy Night : The Night Sky 2017 by Antony Gomez Find out what to look forward to in in the sky this year as well as major Time: 7:00pm, our night sky during 2017! planetary events. Venue: Lower Hutt War Memorial Antony Gomez, President of the Wel- If the sky is clear, we’ll head outside Library lington Astronomical Society, will talk after the talk for a bit of stargazing. you though the amazing things visible Date: Friday 10th March Page 4 VOLUME 47 ISSUE 2 WAS Astrophotography Group Location and updates will be posted on For further details or cancellations the WAS Astrophotography Group contact Edward 021_08304802 or Facebook page closer to the time. Chris 021_ 890222. We will aim for a darker location this Date: Saturday 25th March time to try out our new skills. If the Time: 7:00pm, skies are cloudy we will meet indoors and learn more about processing image Venue: TBD. data. Planetary Accretion An interesting thing happened for plan- terms of dust accreting to planetesi- There is an alternative theory called etary science recently: two papers mals by some unknown mechanism, monarchic growth, but this was aban- (Nature, vol 541 (Dauphas, pp 521 – then these collide to form embryos, doned because it cannot explain first 524; Fischer-Gödde and Kleine, pp 525 which in turn formed oligarchs or pro- why we have the number of planets we – 527) showed that much of how we toplanets (Mars sized objects) and have and where they are, and second think planets accreted is wrong. The these collided to form planets. If this where our water came from. For papers showed that the Earth/Moon happened, they would do a lot of those who attended my WAS talk a system has isotope distributions across bouncing around and everything would few years ago, you will recall I gave a a number of elements exactly the same get well-mixed. Standard computer mechanism based on chemistry that as that found in enstatite chondrites, simulations argue that Earth would causes matter to stick together in spe- and that distribution applied over most have formed from a distribution of cific temperature zones, and that plac- of the accretion. We know that ele- matter from further out than Mars to es the planets are where they are. The ments with multiple isotopes have a inside Mercury's orbit. Dauphas water on Earth was accreted at about variation in isotope ratios that depends showed that Earth accreted from a 1 AU, where the water set cement on the radial distance from the star. reasonably narrow zone throughout its that bound the solids. Enstatite chondrites have structures entire accretion time. Also, the stand- Maybe one day this will be accepted, consistent with being formed much ard explanation that Earth's water and but then again, maybe not. If it is, you closer to the sun than, say, Mars. En- biogenetic material came from carbo- can say you were the first to hear it statite chondrites are also very dry. naceous chondrites must be wrong. and that was at WAS. The ruthenium isotope analysis falsifies The standard theory, called oligarchic the theory that any significant amount Ian Miller growth, explains planetary formation in of water arrived from such chondrites. Movie: Hidden Figures WAS received the following email to be of interest to many of our mem- from John Holmes: bers. It is about the lead up to the Mercu- ry spaceflights, and the work done by “I'd like to recommend to members that, some people subject to some severe social if they haven't already, they go see the issues.” film Hidden Figures. We saw it yesterday night; it is a superb film, and likely Page 5 VOLUME 47 ISSUE 2 Solar Eclipse Provides Coronal Glimpse This article is provided by NASA Space Place. 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