Friday 30 July 2010

Abrams Planetarium - Night Sky Notes



Wednesday 28 July 2010

Into the Looking Glass

Into the Looking Glass   (Visit the site)

Recently, technicians at NASA's Marshall Space Flight Center in Huntsville, Ala., completed a series of cryogenic tests on six James Webb Space Telescope beryllium mirror segments at the center's X-ray & Cryogenic Facility. During testing, the mirrors were subjected to extreme temperatures dipping to -415 degrees Fahrenheit, permitting engineers to measure in extreme detail how the shape of the mirror changes as it cools.

The Webb telescope has 18 mirrors, each of which will be tested twice in the Center's X-ray & Cryogenic Facility to ensure that the mirror will maintain its shape in a space environment -- once with bare polished beryllium and then again after a thin coating of gold is applied.

The cryogenic test gauges how each mirror changes temperature and shape over a range of operational temperatures in space. This helps predict how well the telescope will image infrared sources.

The mirrors are designed to stay cold to allow scientists to observe the infrared light they reflect using a telescope and instruments optimized to detect this light. Warm objects give off infrared light, or heat. If the Webb telescope mirror is too warm, the faint infrared light from distant galaxies may be lost in the infrared glow of the mirror itself. Thus, the Webb telescope's mirrors need to operate in a deep cold or cryogenic state, at around -379 degree Fahrenheit.

Image Credit: NASA

Friday 23 July 2010

"On August 27th Mars will look as large as the full moon."

And finally, "NO ONE ALIVE TODAY WILL EVER SEE THIS AGAIN."
Those are snippets from a widely-circulated email. Only the first sentence is true. The Red Planet is about to be spectacular. The rest is a hoax.

Here are the facts: Earth and Mars are converging for a close encounter this year on October 30th at 0319 Universal Time. Distance: 69 million kilometers. To the unaided eye, Mars will look like a bright red star, a pinprick of light, certainly not as wide as the full Moon.

Disappointed? Don't be. If Mars did come close enough to rival the Moon, its gravity would alter Earth's orbit and raise terrible tides.

Sixty-nine million km is good. At that distance, Mars shines brighter than anything else in the sky except the Sun, the Moon and Venus. The visual magnitude of Mars on Oct. 30, 2005, will be -2.3. Even inattentive sky watchers will notice it, rising at sundown and soaring overhead at midnight.

You might remember another encounter with Mars, about two years ago, on August 27, 2003. That was the closest in recorded history, by a whisker, and millions of people watched as the distance between Mars and Earth shrunk to 56 million km. This October's encounter, at 69 million km, is similar. To casual observers, Mars will seem about as bright and beautiful in 2005 as it was in 2003.

Although closest approach is still months away, Mars is already conspicuous in the early morning. Before the sun comes up, it's the brightest object in the eastern sky, really eye-catching. If you have a telescope, even a small one, point it at Mars. You can see the bright icy South Polar Cap and strange dark markings on the planet's surface.

One day people will walk among those dark markings, exploring and prospecting, possibly mining ice from the polar caps to supply their settlements. It's a key goal of NASA's Vision for Space Exploration: to return to the Moon, to visit Mars and to go beyond.

Every day the view improves. Mars is coming–and that's no hoax.
Original Source: NASA News Release

Tyd om jou Lidmaatskap te hernu of om aan te sluit.




 Hernu jou lidmaatskap by die Bloemfontein Sterrekundevereniging
of sluit aan.

Besoek die webtuiste. www.assabfn.co.za


    Dis weer tyd om jou lidmaatskap by die Sterrekunde vereniging van Suid-Afrika te hernu of om aan te sluit .

    Besoek hulle webblad  om die aansoekvorm af te laai en ook om meer te wete te kom van die vereniging.

    Sunday 18 July 2010

    Nuwe verbeterde : "Star Gazer’s Deep Space Atlas, Outdoor Viewing" (Herhaling)


    Op 1 Junie 2009 het ek die eerste keer oor die "Star Gazer’s Deep Space Atlas, Outdoor Viewing" geskryf. Nou is die die nuwe verbeterde weergawe hier.  Dit is nou beskikbaar. Bestel dit gerus.
    Hoekom die opgewondnheid.
    • Dit is vir die Suidelike halfrond saamgestel. 
    • Dit is gemaak om buite by jou teleskoop of verkyker gebruik te word
    • Blaaie is doubestand. Wonderlik vir die vroegoggende buite.
    • Bladsyagtergrond is swart met wit teks en voorwerpe daarop.
    • Konstellasies in die naghemel word maklik opgespoor.
    • So ook die voorwerpe in die naghemel.
    • Daar is `n “Sky Tour” om jou te help om die boek te gebruik.
    • Kwaliteit drukwerk 
    • Lees weer 1 Junie se blog in die argief.
    • Baie ekstra inligting oor sterrekunde berskikbaar.
    •  Daar is geen sokkerstatistiek in nie. Niks van FIFA nie.

      Meer inligting en voorbeeldbladsye is hier beskikbaar:

      1& 3 is dieselfde. Bestelinligting is by 1 beskikbaar.
      2 & 3 is dieselfde voorbeeldbladsye
    1. Voorbeeldbladsye en kontakinligting in Powerpoint. Klik hier (2M)
    2. Voorbeeldbladsye en kontakinligting in PDF-formaat . Klik hier  (2M)
    3. Inligting op webblad. Klik hier
    4. Opsommende inligting en hoe om die atlas te bestel:  Klik hier


     
    To order a copy, please contact:
     For more info contact Wayne:
     Cell072 465 7739.

    Title: Star Gazers Deep Space Atlas, Outdoor viewing.
    Author: Wayne Mitchell.
    ISBN: 978-0-620-41105-9.
    Edition: Second.  Published: April 2010.
    Size: A5 (210x150 mm)
    Pages: 270. Laminated covers and varnished inner pages.
    Cost: R399. Registered postage (including tracking number) R65.      

    Groete

    Hannes Pieterse
    ASSABFN


    Atlas release date: Mid June 2010
    Atlas release date: Mid June 2010

    KAROO STARPARTY 2010 (Herhaling)

     
    Dit het klein begin in 2009. 
    Skud jou reg vir Suid Afrika se eie Karoo "starparty" in 2010.
    Naas ScopeX gaan hierdie die geleentheid wees om elke jaar by te woon.
    Kom pluk `n ster in die Karoo!

    Plek: Kambro Padstal by Britstown   GPS S30°-25-00.3 E23°-33-56.1
    Datum: 6 - 9 Augustus 2010
    Hoe ver: Klik hier   N1 en N10 = 413km    of R64     N12   = 428km
    (Bloefontein tot by Britstown)
    Southern African biennial Symposium of the ASSA

    The Pretoria branch of ASSA is proud to announce the dates for the Southern African biennial Symposium of the ASSA. The symposium will take place at the Silverton campus of the Council for Geoscience on Thursday 7 October 2010 and Friday 8 October 2010. Click to download a pdf or doc registration file with full information.The symposium will focus on light/spectrum pollution and people interested in delivering papers are invited to send a short synopsis to the Committee. See detail at: download pdf document

    • More information from: Andrie van der Linde, cellphone: 0836324894 or e-mail

    Thursday 8 July 2010

    The Complete Sky & Telescope: Seven Decade Collection.


    All of S&T on DVD
    Rumors have been flying around for months, but now it's official. Starting today, we're taking orders for The Complete Sky & Telescope: Seven Decade Collection.
    Click above for full information on the DVD collection — and to order your own copy online.
    This set of eight DVD-ROMs includes every issue published from November 1941 through December 2009, plus a unified index for the complete set with full text search for every word ever printed.

    I don't know if you're excited, but I sure am! For anyone interested in the history of astronomy, the back issues of Sky & Telescope are a goldmine. That's why the 3-by-6-foot bookcase containing bound volumes of all of S&T is the most precious resource in our offices — even more valuable than the thousands of books that have been acquired over the years both by the magazine as a whole and by the individual editors.


    Chairman’s Chat
    by Gary Els, Canopus July 2010
    monthly newsletter of the johannesburg centre of assa
    Visit and download Canopus
    Those of us who enjoy spending hours viewing through an eyepiece, have to brave the
    elements outdoors, and while summer is the most comfortable, there are the clouds and
    seasonal rain that washes out many a good night's observing.

    The problem is that best sky viewing is in winter, and while family and friends think you are
    crazy, and at times we agree, some of the best objects are visible at this time of year.

    Just take the number of objects that are visible in the southern sky in the early evening,
    just too many to name that are waiting to fill an eyepiece.

    While the Highveld is experiencing the lowest temperatures since 1994, this should not
    deter us from taking advantage of moisture-free skies and hunting down those objects
    we have not yet seen. So here are some tips to help in viewing at this time.

    - Dress in layers, maybe starting with thermal underwear, always a good gift to receive.
    I find a top with a hoodie is best, and together with a beanie it keeps the ears even
    warmer;
    - Wear good boots and warm socks, which are always something we tend to overlook,
    until it’s too late and frozen feet soon put an end to viewing;
    - Good gloves are important, but check out some hunting gloves that have a flap for
    quickly removing your fingers for focusing. Chemical hand warms are cheap and
    may help to revive cold hands;
    - Stay out of the wind, as a mild breeze can have a wind chill factor of 5 degrees less
    than the ambient temperature;
    - Take breaks every hour or so and go inside and enjoy a hot mug of your favourite
    observing liquid;
    - A few short bursts of a hairdryer helps to get rid of dew on lenses, and could also help
    to warm other extremities;
    - Keep your green laser in your pocket so that it stays warm, as they simply don’t work if
    they get too cold.

    So if the soccer fans can endure hours in the cold, we can also view our favourite team
    of sky objects with a little help from these cold weather tips.

    Gary