Saturday 9 August 2014

10 August 2014 - The largest Full Moon for the Year


Image of the Moon taken over Table Mountain, credit: Dr Steve Potter, SAAO.

Source: SAAO

Did you know that the Moon travels around the Earth in an oval shaped or elliptical orbit rather than a circular one? The average distance between the Earth and Moon is 384,400 km. However, because of its elliptical path, the distance to the Moon varies depending on where it is in its orbit around Earth. At its closest point or perigee, the Moon is about 50,000 km closer to Earth than at its most distant point (called apogee).

Full Moons that occur when the Moon is close to or at perigee are called Supermoons and they appear slightly larger and brighter than usual. There is nothing magical about a Supermoon, it is simply a coincidence that full moon has occured when the Moon is near to its closest point to Earth. Just like an aeroplane looks larger the closer it is, so does the Moon.

Read more...

Thursday 7 August 2014

Meteorites: A Southern African Perspective


Meteorites are the remnants of meteors from outer space that have survived the corridor of fire through Earth's atmosphere and landed on our planet. Rare, and bearing secrets about the formation of our Universe, these 'treasures from space' have fascinated people ever since they were first identified in the late 18th century as extraterrestrial arrivals.

This jam-packed book by enthusiast and collector Ronnie McKenzie introduces the topic in straightforward language and is richly illustrated with some 200 photographs and diagrams. It discusses how to identify meteorites, where they come from and where they have landed on Earth, the many different types, and how to set about collecting them. It also dispels some of the myths about these stones, and presents some infamous meteorite scams.

A handy basic guide for those new to the topic, and for anyone interested in entering the field of meteorite collecting.

Sunday 3 August 2014

Deep-Sky Hunter Star Atlas


"Deep Sky hunter" is a printable deep sky atlas, designed for serious deep sky observers. It features stars down to 10.2m and DSO down to 14.0m.

This is my second release of a deep sky atlas. It is much more detailed, and covers entire sky with 101 portrait oriented pages. Manual post-editing was performed in order to ensure readable and non-cluttered charts. In addition, the atlas features 8 pages with 21 supplement "zoom" charts of galaxy clusters and densly populated areas, and indications of over 500 best objects (Messier, Caldwell, Herschel 400, SAC's best).
I designed this atlas with A3 page size in mind, however you may find it usable on A4 as well. In terms of scale and amount of detail - "DeepSky Hunter" falls between Sky Atlas 2000 and Uranometria 2000.
- Michael Vlasov

Here you can see a comparison with other atlases.

Note
- Print back to back on light 200gram carton (A3).
- It is searchable in Adobe Pdf Reader on your computer.  (Search the constellation or the NGC, etc.)
(Hannes Pieterse)

Thursday 31 July 2014

Rosetta's comet rendezvous


On 6 August, after a decade-long journey through space, ESA’s Rosetta will become the first spacecraft in history to rendezvous with a comet. Members of the media are invited to join ESA at its European Space Operations Centre in Darmstadt, Germany, to mark this momentous occasion.

Since its launch from Europe’s Spaceport in Kourou, French Guiana on 2 March 2004, Rosetta has travelled more than six billion kilometres, passing by Earth three times and Mars once, and flying past two asteroids.

For the most distant part of the journey, when it travelled out to the orbit of Jupiter, Rosetta was put into deep-space hibernation for 31 months, waking up on 20 January 2014 for the final leg of its epic journey to Comet 67P/Churyumov–Gerasimenko.
Now, with less than 10 000 km to go, Rosetta is preparing to arrive at its destination.
Read more...

Saturday 26 July 2014

Monday 9 June 2014

Iridium 3 with a spectacular double flair

Click to enlarge

Iridium 3 started out as a -8.2 Magnitude flair but no-one expected the second flair. The first was on time (top) and the second one a bonus. Notice the second satellite in a northern direction in the middle of the image.Still trying to identify it!  Then two bright lines are the pointer stars next to the Crux constellation.

Image info:  192 images were stacked with Starstax; Camera on tripod; Remote control;  ISO 800; 10 sec exposures; f4.5; Moon a big hinderance.

Friday 6 June 2014

Vrystaat Sterrefees / Free State Star Party


Vrystaat Sterre Partytjie                         
( English version below)

ASSA Bloemfontein nooi u na twee nagte van waarneming en verwondering van die Winterkonstellasies in die unieke Vrystaatse naghemel.  Daarmee saam gedurende Saterdag 28 Junie, is daar praatjies en besprekings oor onder meer teleskoopkollimasie deur Brett du Preez.

Plek: Gansvlei-gasteplaas tussen Brandfort, Bloemfontein en Winburg. (G.P.S.: Suid 28°47'49.9" en Oos 26°28'23.1"; Elevasie: 1395m).
Tyd: Vanaf 17:00 op 27 Junie tot omtrent 09:00 op 29 Junie 2014, dus twee nagte.
Koste: R80 per persoon per nag, wat insluit 'n bed met paslaken, ablusiegeriewe, volledig toegerusde kombuis en eetgerei, hout en braai geriewe soos roosters en selfs potte.
Benodigdehede: U eie waarnemingstoerusting soos teleskope, vêrkykers, kameras, sterkaarte, stoel/tafel, beligting (beperk tot die flouste rooi liggie wat jy het...!) ens.  U eie kos en drinkgoed - genoeg vir die tydperk wat u daar bly - naaste winkel is omtrent 40km vanaf die plaas.  Warm klere en warm slaapgoed: onthou dis in die middel van die winter en dis in die middel van die Vrystaat...!!!
Bespreking: Indien u belangstel, antwoord asseblief per e-pos na assabfn@gmail.com, en doen dit asseblief nie later as 20 Junie 2014 nie.  Geen voorafbetaling is nodig nie.  Daar is huisvesting vir 40 mense so laat weet asseblief vroegtydig. 

Finale informasie sal per e-pos gekommunikeer word op Maandag 23 Junie aan diegene wat bespreek het teen daardie tyd.

Free State Star Party

ASSA Bloemfontein invites you to two nights of wonderful observation of the Winter Constellation in the unique Free State night skies.  Including, during Saturday 28 June, there will be talks and discussion on telescope collimation by Brett du Preez.
Venue: Gansvlei guest farm situated between Bloemfontein, Brandfort and Winburg (G.P.S.: South 28°47'49.9" and East 26°28'23.1"; Elevation: 1395m).
Time and duration: Two nights, from 17:00 on 27 June to about 09:00 on 29 June 2014.
Cost: R80 per person per night, which includes a bed with a fitted sheet, ablution facilities, fully equipped kitchen with cutlery, wood and braai facilities such as braai grids and even pots.
Requirements: Your own observation equipment such as telescopes, binoculars, cameras, star charts, chair and table, lighting (confined to the weakest and reddest light you own...!) etc.  Your own food and drinks for the duration of your stay - the nearest shops are about 40km from the farm.  Warm clothes and bedding: remembers it is mid-winter in the middle of the Free State...!!!
Booking: Please answer by e-mail to assabfn@gmail.com not later than 20 June 2014 if you are interested.  No pre-payment is necessary.  There is accommodation for 40 people so please respond soon.

Final information will be communicated by e-mail on 23 June 2014 to those who have booked by then.

Wednesday 21 May 2014

Astrofotografie Werkswinkel vir beginners / Basic Astrophotography Workshop

Foto: Hannes Pieterse
ASSA Bloemfontein bied aan:
‘n Basiese Astrofotografie Werkswinkel.
(English version below)
Aanbieder: Brett du Preez, lid van ASSA Bloemfontein en ervare Astrofotograaf.
Plek: Boyden Sterrewag
Tyd: Saterdag 24 Mei 2014, vanaf 15h00.
 Toegang: Gratis vir Klublede en R100-00 per persoon vir nie-lede.
Weens die aard van die Werkswinkel, kan slegs 30 persone geakkomodeer word.
Bespreek asseblief deur per e-pos te stuur aan assabfn@gmail.com
 Program:15h00 vir 15h30 – Ons begin op die Platform: Almal pak hul goed uit en slaan op wat hulle saamgebring het.
15h30 - 16h30 – Gesels oor wat ons gaan doen en begin die Werkswinkel met die afneem van Son (bring hoedens ens saam….).  Brett sal ‘n beperkte hoeveelheid son-filter saambring vir afneem van die son.  Bring ook ‘n skêr of matmes, karton, dubbelkantige kleefband en gewone kleefband of kits-gom vir die maak van sonfilters.
16h30 - 18h00 – In die Ouditorium: stapsgewyse demonstrasie van die omskepping van die son se data na 'n foto. Bring asseblief u eie rekenaars en geheue-stokkie (“flashdisc”) saam. Brett sal sagteware verskaf en ook basiese prosesering demonstreer op 'n foto van die naghemel.
18h30 - 19h30 - 'n Kort praatjie oor astrofotografie. Die plan is om as groep saam te gesels. Brett sal begin met die basiese beginsels asook 'n verduideliking van die konsep oor "noise". Hannes Pieterse verduidelik ook die gebruik van die “barndoor“ montering vir nag-hemel fotografie.
20h00 - 22h00 – Terug op die Platform wys Brett hoe om polêre oplyning (“polar alignment“) te doen met 'n kamera asook watter tipe fotografie mens kan doen met die minste moeite en met ‘n basiese kamera….
Onthou asseblief:
Almal wat fotografiese en ander toerusting saambring, moet weet hoe om dit te gebruik sodat ons nie gedurende die werkswinkel tyd hoef te spandeer om basiese gebruike aan te leer nie.  Toerusting om saam te bring sluit in: kamera, driepoot, genoeg batterye (daar sal kragpunte op die Platform wees), nodige verbindingskabels en afstandsbeheer kabel, tafeltjie om op te werk ens: eerder teveel as te min.  
Daar sal tussendeur geleentheid wees om ietsie te eet: elkeen bring sy eie verversings.  Daar sal kookwater wees vir diegene wat koffie of ‘n soppie will maak. 
ASSA Bloemfontein presents:
A Basic Astrophotography Workshop.
Presenter: Brett du Preez, member of ASSA Bloemfontein and experienced Astrophotographer.
Venue: Boyden Observatory
 Time: Saturday 24 May 2014, at 15h:00.
 Admission: Club members free.  Non-members: R100-00 per person.
Only 30 persons can be accommodated.
Send  e-mail to assabfn@gmail.com to book
Program: 15h00 for 15h30 – We start on the Platform:  unpacking and setting-up of equipment.
15h30 - 16h30 – Discuss the program and start the Workshop by taking a photo of the Sun (remember to bring a hat…).  Brett will demonstrate the making of a solar filter: he has a limited stock of solar film which he will provide.  For this, please also bring along scissors or a carpet knife and carton, double sided tape and normal tape or fast-drying glue.
16h30 - 18h00 – In the auditorium: step-by-step demonstration of the conversion of the Sun data to  a photographic image.  Please bring your own computer and flash disc. Brett will provide the necessary software and also demonstrate the basic processing of a night-sky image.
18h30 - 19h30 – A short discussion on Astrophotography, also involving the audience.  Brett will also explain the importance of the concept of “noise”.  Hannes Pieterse will demonstrate the use of the “barn door” mounting for night-sky photography.
20h00 - 22h00 – Back to the Platform: Brett demonstrates polar alignment using a camera and also demonstrates what type of photography can be performed with the least effort and with a basic camera.
Please remember:
Make sure that you know how to operate all the equipment you bring along: you do not want to figure out how to use your equipment during the workshop, you actually want to use it.  This equipment can include:  camera, tripod, enough batteries (power outlets are available on the Platform), all necessary connecting cables and remote control cable, a small table to work on: rather bring too much than forget something vital…!  
There will be time to eat/drink something in between: please bring your own refreshments.  There will be boiling water for coffee and/or soup.