Blog Posts
Central Star Party 2017
Central Star Party has been established to hold annual star parties in the central North Island for the benefit of the astronomical community of the North Island of New Zealand. The goal of the organisers is to provide a fun social astronomical gathering laced with talks, activities and telescope viewing. It is a not-for-profit organisation so any proceeds go back into making the next year’s party even better.
CSP 2017 took place from Thursday 19th to Monday 23rd January. There were over 70 attendees this year, most of them staying on site. This was mainly because of the amazing facilities available at the camp, which has a brand new hall (with air-conditioning), kitchen, meeting rooms and bunk rooms as well as powered sites for tents and caravans. The Hall has a large canopy all the way round so it is always possible to find a side that is out of the wind, rain and sun. There was also a large professional social marquee set up in the bottom field. It was great to see many old faces turn up – people who had stopped coming to New Zealand summer star parties many years ago.
The weekend began with a lazy day of settling in – a time to meet old friends and catch up. Free pizzas were provided for everyone so no-one had to worry about cooking. Everyone was then treated to a superb night of observing and deep-sky astrophotography with over 10 telescopes set up. The Friday was a beautiful day with more people arriving. A sausage sizzle started the evening’s program, cooked in a BBQ-trailer provided by WESTPAC. This was followed by a talk on exobiology by Bethany Jones and a talk by Rolf Olsen - astrophotographer extraordinaire - on ultra-deep sky imaging. The time came again for observing and deep-sky imaging. The seeing on this night was even better than the first night and many people were still up well into the early hours.
On the Saturday the wind began to pick up. This wasn’t a problem during the day as the program of talks kept everyone inspired. The day began with a Pixinsight workshop, led by Rolf Olsen, for the many astrophotographers present. Talks followed by Gary Sparks, Graham Palmer, Simon Lowther, John Drummond and Gordon Hudson. Following the telescope trail, in which the owners explained the virtues of their telescopes, the fish and chip supper arrived. As always the Clive chip shop produced a lovely meal for everyone.
With bellies full the evening’s program was kicked off by Carl Knight. The raffle was then drawn followed by a second talk by Rolf Olsen. Unfortunately the wind had really picked up and so no viewing was possible. Time was spent socialising, watching movies and tying down tents! The night turned out to be tough on many of the tents and the poles on many of them split.
The Sunday program began with another sausage sizzle and was followed by talks by Michael Mackrill, Mike Bull, Otto Gruebl and Bruce Ngataieruai. The camp site is in the fortunate position to be close to a public planetarium so on the Sunday afternoon there was a free trip to a special show in Napier. Many people took the opportunity to have a meal out in a restaurant after. Unfortunately the wind had not died down and so some people decided they didn’t want to chance another night with tents with broken poles so they packed up. For those that didn’t there was an astro-quiz as well as an excellent documentary. By this point the wind had dropped and although the sky was not completely clear it was still possible to get some telescope viewing done. Overall a fantastic weekend eventuated. Despite the windy Saturday and Sunday three nights were spent observing and undertaking photography. The hall wasn’t sweltering, like it was in the old hall, so the talks weren’t difficult to attend. Here’s to next year’s party! |
New Zealand Astrophotography Camp 2015
Between the 13th and 15th November 2015 the Horowhenua Astronomical Society hosted the third New Zealand Astrophotography Weekend. As was the case in previous years the event was a total success. The difference this year was that practical astrophotography was actually achieved. As guests arrived on the Friday it was obvious it was going to be a stunner of a night so people immediately set up their gear and the official opening was shelved until the next day. All sorts of astrophotography was undertaken including deep sky imaging through telescopes/camera lenses to nightscapes. Some attendees were up until sunrise at about 5.30am. Apart from a rather annoying light show at the boat house it was a perfect night The Saturday morning was beautiful sunshine so two solar telescopes were set up for imaging. One enabled imaging in Hydrogen alpha and the other in Calcium-K.
(Photo: Edwin Rodley) Following the solar imaging the first official talk began. Professor Bill Williams gave a really interesting talk about how light that comes from deep space gets captured by digital cameras and how they then transform the captured light into digital data. Bill's talk was followed by Stephen Chadwick who discussed what equipment is required to undertake deep sky astrophotography and after lunch the first of the processing workshops was undertaken. Steve Lang and Roger Morgan did a practical demonstration of how to process images using Pixinsight. Jim McAloon was next up showing us how he images and processes planetary images. (Photo: Jonathan Green) Peter Aldous then gave his RASNZ Gifford Eigby lecture on how to build observatory domes. He showed images of some of the countless domes he has personally made during his life. Our third software talk was given by Jonathan Green in which he discussed stitching images together to produce wide Nightscape panoramas. After a great fish and chip supper from Mr Grumpy’s Steve Lang described how to build a cheap and easy observatory in the back yard. The day’s talks ended with a fourth software talk – this time about the processing software known as IRIS.
(Photo: Otto Gruebl) The weather turned on the Saturday night so there was no more imaging to be done. This, however, left a whole evening to process the data that had been gathered the night before. The Sunday was cloudy so there was no solar imaging to be done but George Ionas kicked off the talks by processing the data he had captured the night before on the big screen. Otto Gruebl from Wangarei also showed us the images he had taken the day before on his Calcium-K telescope. Amit Kamble finished off the talks by explaining how you don’t need dedicated astronomy software to process astronomical images.
All in all it was a fantastic event with wonderful feedback.
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StellarFest 2015 by Ian Cooper
At the 4th StellarFest event held at the Foxton Beach Bible Camp this weekend we had a mixed night weather wise but around 10.00 hours U.T. it cleared enough to get the cameras and 'scopes back out to capture comet US 10 Catalina sitting up in Pavo. ![]() I got this at 11.31 U.T. with my Nikon D3100 with a 35mm lens at f/2.8 30 seconds on ISO 3200. ![]() The second shot was 4 minutes later when there was a strong upsurge in activity. Activity waxed & waned right through the night, but cloud along the southern horizon kept us from seeing the whole display. |
Total Lunar Eclipse April 5th by Edwin Rodley
The weather in Wellington was not looking too promising during the day and into the evening - severe wind gusts and clouds had left me thinking that there was no chance of seeing the eclipse. By 10pm at night the weather had cleared up, the wind had gone away and it was clear, calm and warm. I knew I was in for a late night of observing. I caught up with family on the Kapiti Coast in the early evening, then I called by Robin Warnes’ place, hoping that the sky would clear up that way so we could observe the eclipse. It was a good move as Robin had his 12” Dobinson set-up. I had brought my binoculars and camera. We had to contend with patchy clouds and mosquitos, but we managed to watch the eclipse progress and were able to see the colours, the views with the binoculars were great, and the view through the Barlow on the 12” Dob was really clear as we watched the Earth’s shadow move across the moon. This eclipse was advertised as the shortest total lunar eclipse. According to Sky and Telescope it may have only been a 99.9%, not a total eclipse. We watched with interest near totally, but we saw a slight bit of the moon in sunlight. It was a great eclipse to stay up late for, and with daylight savings time ending that same morning, it made me extra tired the next day. My wife wasn’t too impressed to be woken up at 2.30am, when I snuck in the door! By Edwin Rod
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Astrophotography Weekend Great Success
On the weekend of 21st-23rd November 2014 the Horowhenua Astronomical Society hosted its second annual astrophotography get-together at Foxton beach, which is situated an hour and a half north of Wellington. The weekend promised to be a great event enabling like-minded people from all over New Zealand a chance to meet and discuss their favourite pastime.
Some of the attendees (Photo: Ian Cooper)
In the end it turned out to be even more successful than last year’s event with over 50 people attending from all over New Zealand – from as far away from Geraldine, Christchurch, Nelson, Auckland, New Plymouth, Wellington and Napier - making it a truly national event. The purpose of the weekend was to facilitate learning through shared knowledge of all aspects of using digital cameras to photograph the night sky, whether to capture the beauty of the universe, undertake scientific observations or both. There were people present who are interested in all aspects of astrophotography, from deep sky objects, nightscapes, lunar, solar and aurorae to hunting for comets and supernovae. So there was something there for each participant to teach others about, and to learn for themselves too. As guests arrived on the Friday afternoon it was obvious that the weather was not going to be kind that evening. Although it was not raining it was cloudy and very windy. However, many people set up their astrophotography gear anyway, next to the ‘imaging courtyard’, for point of conversation as well as in the vain chance that the sky might clear. After the official opening, by the Horowhenua Astronomical Society president Stephen Chadwick, a slideshow of 150 different images, taken by 10 of the attendees, was presented on the big screen. This random selection revealed the great range of interests that astrophotographers have in New Zealand as well as what can be achieved with different equipment. The slideshow was followed by a group discussion, which provided an opportunity for each participant to explain how they had photographed and processed their images. The Saturday programme was supposed to begin with a practical solar imaging workshop with George Ionas. Unfortunately the Sun was nowhere to be seen so instead the day began with the first of a series of talks. Bill Williams, Professor of Physics at Massey University, gave a talk entitled ‘Wasting Light’. He discussed the process by which CCD sensors capture photons and how optical aberrations can limit the acquisition of light that is so essential for imaging faint astronomical objects. The second talk was given by Peter Aldous, from Geraldine on the South Island, as well as Robert McTauge, by live internet link, from Timaru. It was made possible with the assistance of the Gifford-Eiby Memorial Lectureship Scheme that is administered by the Royal Astronomical Society of New Zealand. The talk was about astronomical imaging using ‘Hyperstar’. This is a method that enables a Schmidt-Cassegrain telescope to be converted into a fast f/2 imaging system. They explained how it functioned and then gave examples of how much data could be captured in short periods of time. As Peter had brought all the equipment with him guests were able physically to see for themselves how the system works.
Perter Aldous and Robert McTauge (live via Skype on the screen) explaining the advantages of Hyperstar Imaging (Photo: Amit Kamble) After lunch Stephen Chadwick introduced the audience to a piece of software called ‘CCDInspector’. He showed how it can be used to easily collimate a telescope with a camera in situ. He then explained what causes field curvature and how the software can be used in order to quickly determine the correct spacing between sensor and field flattener in order to achieve a nice flat field. Lastly, he showed how the software can monitor changes in focusing and seeing in real time.
Stephen Chadwick’s presentation on CCDInspector. (Photo: Edwin Rodley) This was followed by the first processing workshop of the weekend, facilitated by Steve Lang. He introduced the processing software ‘PixInsight’ and went through all the steps necessary to move from unprocessed data to the final result using one of his images of the Eta Carinae Nebula.
Steve Lang processing the Eta Carinae Nebula at the PixInsight Workshop. (Photo: Jonathan Green) The late afternoon session began with a theoretical presentation, given by physics lecturer Dr Steve Keen. His talk, ‘a beginners’ guide to ISO and exposure’, was aimed at dispelling myths about what the term ‘ISO’ actually means when used in the context of digital cameras and how manufacturers exploit misunderstandings for marketing purposes. Jonathan Green presenting many of his wide field astronomical images (photo: Ian Cooper) Jonathan Green then presented many of his inspirational nightscape photographs as well as wide field mosaics of the Milky Way. He showed what can be done with a DSLR on both a stationary tripod as well as on a small portable tracking mount. The Saturday afternoon session ended with the second processing workshop of the weekend, this time facilitated by Stephen Chadwick. He explained some of the processing techniques that can be utilised when using ‘Photoshop’. The fish and chip supper then arrived, thanks to one of the best chippies in New Zealand – Mr Grumpy! The camp cat was delighted to help polish off any spare fish that was available.
The camp cat (photo: Edwin Rodley)
As night began to fall the weather was still looking very grim so it seemed unlikely that any practical imaging would be possible. But we still had some fascinating presentations ahead. Amit Kamble started the evening session explaining how he processes his fantastic nightscapes. He used a particular example of the Milky Way setting above a road to show all the steps necessary to turn a series of photographs into one extended panorama. This was followed by a talk by Peter Aldous on supernova hunting from a back yard using a CCD camera. Peter has discovered many supernovae over the years and he showed the steps needed to do this as well as the dedication necessary. He ended by explaining why he no longer undertakes this pastime and why he now prefers to capture the beauty of the universe using his ‘Hyperstar’ system. As the skies were still not clear a few relaxing audio visual presentations were shown. Firstly, Jonathan Green showed a slide show of all the entries in the ‘Harry Williams Astrophotography Trophy’. This was followed by two videos of images taken by Stephen Chadwick. One was called ‘A journey along the southern Milky Way’ and the other ‘A trip around the Clouds of Magellan.’ These presented wide field shots of the Milky Way and the Clouds of Magellan respectively. By zooming in on each object it was possible to look in greater depth at many of the deep sky treasures that they hold. At this point it was announced that the skies were clearing. Unfortunately the clouds were fast moving so as soon as one hole appeared another disappeared. However, this was just enough to tempt a few intrepid souls outside to set up their gear. It was quite frustrating though as just as an object was framed it disappeared again amongst the clouds. But, at last, one image was taken. At 9.30pm Adam Corbett managed to get an image of the Great Orion Nebula.
(M42 by Adam Corbett) Equipment: Modified Canon 6D, Celestron CGEM mount, Stellarvue 80mm refractor, 1x1min exposure unguided at ISO 1000. Sunday began and again no solar imaging was possible. However we had a talk by Frank Andrews on how to get started in astrophotography using a DSLR. This was followed by the third processing workshop, this time led by George Ionas, on how to process solar images using ‘Registax’, ‘Microsoft ICE’ and ‘Photoshop’. His intention had been to use data acquired during the weekend but as this had not been possible he used some that, fortuitously, he had brought with him.
George Ionas leads a workshop on solar image processing (photo Edwin Rodley) The weekend ended with a talk by Ian Cooper on photographing Aurora using many of his own images as examples.
Adam Corbett discusses his imaging set-up to other guests (left-right Andrew Drawneek, Amit Kamble, Adam Corbett (in front), Milind Ghandi, George Ionas, Simon Hills) (photo: Jonathan Green)
Although there had been very little practical imaging undertaken the weekend was a great success. The presentations were all informative and useful but most of all, as was obvious from the constant din of chatter throughout the building, people were learning from each other. Here’s to the third astrophotography get-together next year.
Horowhenua Astronomical Society |
Cosmological Confusion: Tamara Davis Lecture by Alan Little
Dr Tamara Davis (University of Queensland, Australia) "Cosmological Confusion" Dr Tamara Davis, the
distinguished astronomer from the University of Queensland, Australia spoke to
a crowd of some 114 people at Levin’s Waiopehu College on Monday evening 22nd
September and next morning to students from the district's Colleges also at
Waiopehu. Horowhenua Astronomical Society was delighted to be given the
privilege of hosting Dr Davis who is in New Zealand speaking as part of the
Royal Astronomical Society of New Zealand 2014 Beatrice Hill Tinsley Lecture series.
Dr Davis is a young and inspiring cosmologist who spends her time investigating
why the expansion of the universe is accelerating and was part of the WiggleZ
Dark Energy Survey, which made one of the largest ever maps of galaxies in the
universe using supernovae to measure the properties of “dark energy”. She
proved to be an excellent engaging communicator who turned complex concepts
into everyday language. Dr Davis obviously enjoys making science accessible to
the public and interacted very well with the audience. For more information
about our guest please visit her private web page: http://www.physics.uq.edu.au/download/tamarad/ |
StellarFest 2014 by Carl Knight
Folks, if you are not already, then you should plan to get to StellarFest 2015. This year's event was brilliant.
Held at the Foxton Beach Bible Camp, the site has excellent accommodation and, given it is on the outskirts of Foxton Beach itself, remarkably dark skies. So what did we do at StellarFest 2014? In the daytime there were talks and solar observing...
Friday night was clear with some breeze. Warm clothes were the order of the "night". The central bulge of the Milky Way was fully in view overhead. For those that do not live in the country it was a real treat. The only light pollution came from near by street lights, but compared to a city view, hardly mattered. The mornings were cold to say the least. Frosty starts to the days and the hall was a cold place to sit for the talks!
Space was available in the hall and laptops were set up allowing anyone to see the image processing in action. Saturday's talks were:
Saturday's observing began with plenty of action on the field adjacent to the main hall at the campsite.
A variety of telescopes were set up. These included Dobsonians, SCTs and Refractors.
arrived - a little after 10pm - and put an end to the evening. It cleared sporadically after 11pm. It was very cold so in combination with the cloud, most people could be found inside watching the story of Patrick Moore's life: 84 not out. Sunday began with frost again and more solar observing.
All and all a very well worthwhile event and I look forward to attending again next year. Particular thanks go to:
- Carl. |
Dame Jocelyn Bell-Burnell Talk Packs Them In
Dame Jocelyn Bell-Burnell Packs them in at Te Manawa!
On June 11th Dame Jocelyn Bell-Burnell gave a lecture at Te Manawa Museum in Palmerston North. The event was hosted by the Horowhenua Astronomical Society and supported by Massey University. The writer had already heard the guest speaker at the recent annual confer-ence of the Royal Astronomical Society of New Zealand (R.A.S.N.Z.) held at Whakatane. Dame Jocelyn was the dis-coverer of the first Pulsar back in the mid 1960’s. Like any good speaker her talks are pitched to the expected audiences at-tending. At Whakatane Dame Jocelyn spoke about, “Transient Astronomy—Bursts, bangs and things that go bump in the night.” In this talk she highlighted some cutting edge observations of exotic objects in deep space that challenge our under-standing of the universe. Dame Jocelyn hinted at the nature of these new type of objects and left us to ponder just what might be behind these mysterious bursts of energy on a scale never be-fore detected. At Te Manawa Dame Jocelyn covered what for many of us is familiar ground but she did it with her own personal energy that brought new life to the story, a story about death and life and the creation of the elements that eventually make us all. The professor certainly showed us how to get some very complex ideas across to a lay audience, albeit a fairly knowl-edgeable one at that. With fifteen minutes to go there was about 40 to 50 people in attendance and we suspected that there would be a flux of late comers before the talk was due to start. We weren’t however prepared for over 250 people who crammed into the room in that last quarter of an hour! Standing room only was the call. A group of school kids sat on the floor at Dame Jocelyn’s feet and you could tell that she was quite delighted with the children’s interaction with her during and after the talk. In the end the Palmerston North event was her best attended lecture on her short 10 day tour of mostly the North Island. She will leave with fond memories of her short time in Palmerston North where she has friends, and we have fond memories of some pleasant chats at dinner later that evening.
Ian Cooper |
Government Controls for Laser Pointers
New controls on high-power laser pointers The Government recently introduced new laws on high-power laser pointers. These devices are useful tools for astronomers to use in observatories or to point out things in the night sky. If you are involved in astronomy and use a laser pointer then you should understand the new controls and how they apply to you. What devices are covered by the new laws? Laser pointers are small hand-held devices that emit a tightly focused beam of light that can be concentrated onto a very small area even over long distances. Although the total power in the beam may be small (a few milliwatts), concentrating this power onto a tiny spot creates a point of very high intensity. The new laws define a high-power laser pointer as a device that: a. in the Director-General of Health’s opinion, is of the kind commonly known as a laser pointer; and b. is battery operated; and c. is designed or intended to be operated while held in the hand; and d. produces a coherent beam of optical radiation of low divergence (i.e., the beam does not fan out like a torch beam); and e. has a power output of greater than 1 milliwatt (mW). Note: the new laws DO NOT cover laser pointers that are 1 mW or less in power. Some other laser devices are also exempt (e.g., surveying equipment). Why were the new controls introduced? The controls were introduced to manage the health and safety risks from high-power laser pointers. There are two main risks from these devices. People may not be aware of the potential harm these devices can cause and inadvertently shine them in their own eyes or other people’s eyes. People maliciously (or ignorantly) shine them at vehicles such as aircraft and dazzle the pilot. Even when shone from several hundred meters away high-power laser pointers can dazzle and cause temporary flash blindness. Distracting or dazzling a pilot in this way for instance, is a serious aviation safety risk, particularly during critical phases of flight such as during critical phases of flight such as during take-off and/or landing. Car drivers, cyclists, and ship crews are also at risk if dazzled by high-power laser pointers. What do the laws do? The new controls cover the importation, sale/supply and acquisition of high-power laser pointers (devices that have a power of greater than 1 milliwatt (mW)). In summary: The Custom Import Prohibition (High-power Laser Pointers) Order 2013 restricts the importation of high-power laser pointers to those people who have obtained authorisation to import them from the Director-General of Health. The Health (High-power Laser Pointers) Regulations 2013 restrict the sale/supply of highpower laser pointers to those who are authorised suppliers and also restrict the acquisition of such devices to those who are authorised recipients. To become an authorised importer, supplier or recipient of a high-power laser pointer most people need to apply to the Director-General of Health using an application form available on the Ministry of Health’s website (there are some exceptions as described below). What do the new laws mean for astronomy societies and their members? Astronomy societies and their members DO NOT have to get permission to supply or acquire high-power laser pointers because the government recognises that they have a legitimate use for such devices. (Note that “supply” means both “sell” and “give for free”.) Astronomy societies and their members still need to apply for permission to import them, however. Under the new controls the Director-General has declared that certain classes of people are approved suppliers or recipients. This means they are exempted from having to specifically apply for permission to acquire or supply such devices. Astronomy societies and their members are one of the few such approved classes of people (other approved classes include those who use laser pointers for scientific, research, or industrial purposes). The ability to have such approved classes of persons recognises that some people have legitimate uses for such devices, will better understand their risks, take appropriate precautions to use and store devices safely, and will be unlikely to misuse their laser pointers (i.e., they will not shine them at aircraft or intentionally shine them at people). The new controls do have some impacts on astronomy societies and their members. The key ones are noted below: If you want to import any high-power laser pointer you will need to complete an application form, send it to the Ministry of Health, and receive an authorisation to import. You need to obtain import consent BEFORE you import the device (otherwise it will likely be seized by Customs and you will have to seek a review of seizure). You also need to be careful that you do not supply any high-power laser pointer to any person who is not authorised to acquire one. While you are entitled to supply a device to other members of an astronomy society (who are also entitled to receive them without seeking permission), you cannot automatically supply a high-power laser pointer to anyone. For example, you cannot simply give or sell your high-power laser pointer to any member of the public if they have not received an authorisation from the Ministry of Health or are part of an approved class. The Regulations contain offences and penalties. For example, supplying a device to another person without having reasonable grounds to believe that the person is authorised to receive it is a breach of the Regulations, and you will be liable to pay a fine. If you wish to buy a high-power laser pointer from a New Zealand-based supplier, you will need to provide them some proof that you belong to an approved class of persons. For example, you could show them a letter from your astronomy Society, on headed paper, confirming that you are a bona fide member. Are any other controls on laser pointers being considered? Yes. The controls mentioned above DO NOT cover possession of laser pointers. That is, people do not have to get any authorisation to possess laser pointers that they already own. However, a proposed law change is currently being considered by Parliament. The Summary Offences (Possession of Hand-held Lasers) Amendment Bill is proposing to make it an offence to be in possession of a high-power laser pointer in a public place without having a reasonable excuse. A similar offence currently exists for knives. Even if this proposed law change is passed by Parliament then astronomers are unlikely to be adversely impacted. Being an approved class of person, entitled to acquire high-power laser pointers under the regulations noted above, and having a legitimate reason to have a laser pointer will provide a ‘reasonable excuse’ (unless the devices are being misused). Ultimately, however, Parliament will decide whether the Bill is passed into law. Where do I get more information? More information about laser pointers, the new controls and their implications for you, and how to apply for authorisation is available on the Ministry of Health’s website: http://www.health.govt.nz/our-work/environmental-health/high-power-laser-pointers You can also email any questions on the new controls to laserpointers@moh.govt.nz |