Happy first birthday, Neptune!

On 12 July, Neptune will celebrate its very first birthday because exactly one Neptunian year -- or 164.79 Earth years -- will have passed since its discovery.

Neptune was mathematically predicted before it was first telescopically observed on 24 September 1846. Astronomer Johann Gottfried Galle and his assistant Heinrich Louis d'Arrest used Urbain Le Verrier's calculations to locate the planet. It was found to be within a single degree of where Le Verrier had predicted it would be and it was the first planet to have been discovered deliberately.

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How to tick the Horesehead nebula of your astro bucket list

Seeing the Horsehead with a filter is a real accomplishment; finding it without one is something to very be proud of!

Dark Nebula w/nebulosity

aka B33, LDN 1630

Minimum requirements to detect: 8-inch scope under dark skies

• More information to to tick this of your astro bucket list

Nog `n maanverduisteringfoto

Frans Human van ASSA Bloemfontein het hierdie samestelling van die totale maanverduistering afgeneem.

Total Lunar Eclipse , 15 June 2011 - Animation

Click on Picture to view eclipse animation

Photos: Hannes Pieterse

Onthou: Algehele Maanverduistering, 15 Junie 2011

 Laai groter grafika af

 Tye volgens The Sky 6:

19:24: Beweeg in Penumbra in
20:23: Beweeg in Umbra in (Verduistering is meer sigbaar)
21:23: Algehele verduistering begin. Maan in in rooi gloed gehul.
23:03 Algehele verduistering eindig. Beweeg in penumbra in. (Maan word meer strokie-vir-strokiesigbaar)
00:04 Maan uit Umbra en in Penumbra.
01:04  Maan uit Penumbra en algehele verduistering is verby.

Reminder: Total Lunar Eclipse, 15 June

NGC 3324, Gabriela Mistral nebula vanaf Boyden-sterrewag, Bloemfontein

Klik om te vergroot

NGC 3324, Gabriela Mistral nebula
Constellation: Carina (Car)
Foto: Brett du Preez, ASSA Bloemfontein

Atik 383L+
280mins Ha data
20mins subs
127mm Apo triplet refractor
Cgem off axis autoguided with Meade dsi pro
Captured with Maxim DL 5, Sigma stacked, processed with startools and Photoshop cs5

ATM: Amaterur teleskoopmakers in Bloemfontein bymekaar

Thinus van der Merwe van ASSA Bloemfontein wys hier hoe `n spieël geslyp moet word by `n inligtingsessie om jou eie teleskoop te bou.

• Meer inligting oor die projek

Die "Jet Stream" beïnvloed jou waarnemingsomstandighede!

 Kliek om te vergroot

 Die Suidelike "Jet stream" soos op 4 Junie 2011 besig om oor Suidelike Afrika te beweeg. Tog as jy na die Wolkekaart van Kobus Botha (hieronder) kyk is dit oopgetrek oor Suid-Afrika.  

Kliek om te vergroot

Hoe gaan die "seeing" vanaand by Boyden wees? Waarskynlik onstabiel. Is dit nie `n nfaktor wat ons amateurs nie in gedagte hou as ons observasieaande beplan nie. Agterna kla ons oor die voorwerpe wat rondspring.

Lees gerus die artikel hieronder wat ek op `n webtuiste raak ge-google het.  Onderaan is 'n paar skakels.

How the Jet Stream impacts astronomical "seeing" 

Source: Astronomy Club of Asheville

"Seeing" refers to the the amount of "blurring" caused by the earth's atmosphere -- most apparent in a telescope using higher magnifications.  Astronomers refer to this atmospheric turmoil as "bad seeing".  Seeing well at high magnifications is only possible when the air is steady.

Excellent seeing means, at high magnification, you will see fine detail on planets.  In bad seeing, planets might look like they are under a layer of rippling water and show little detail at any magnification, but the view of galaxies is probably undiminished.

Bad seeing is caused by turbulence combined with temperature differences in the atmosphere.  The turbulence may be caused by ground level winds as well as higher level air movements created by the jet stream. When the jet stream is overhead, seeing is generally poor.

Bad seeing can occur during perfectly clear weather.  Often good seeing occurs during poor transparency.  It's because seeing is not very related to the water vapor content (transparency) of the air. 

Skakels

- Stel animasie op van Suidelike "Jet Stream" 

-  Grafika van vandag se Suidelike "Jet Stream" 

-  The Atmosphere and Observing - A guide to Astronomical seeing.

-  Predicting the seeing (over Holland) is that possible?! 

-  Chapter 8 -- "Astronomical Seeing"

Deep Space Atlas - Father's day Special

FATHER'S DAY SPECIAL!
Father's Day special of R299 for the Deep Space Atlas for the
month of June. (Usual price R399)
Postage: R45
To order, please use the following email address: wayne.mitchell@penbogroupe.com

For more info about the book visit blog article: Deep Space Atlas

Kom bou jou eie teleskoop!

 Inligtingsessie:  Kom bou jou eie teleskoop! 

Datum: 4 Junie 2011 (Saterdag)
Tyd:  18:00
Plek: Boyden-sterrewag

Aangebied deur die Bloemfontein Sterrekundevereniging

Thinus van der Merwe, `n gesoute teleskoopbouer van die vereniging, met `n hele paar teleskope op sy kerfstok, gaan ons meer oor die projek vertel.

• Hy gaan ook vir ons `n praktiese demonstrasie gee van die stappe om `n spieël te slyp.
  

Vir wie:  Almal wat belangstel om sy eie teleskoop te bou.  `n Lekker gesinsprojek.

Nee, dit is nie net `n projek vir die manne nie. Mia Zeelie, van die vereniging het vroeër haar eie teleskoop gebou.

Waaroor gaan ons praat?

- Koste van so `n projek.
- Hoe gaan ons die projek aanpak?
- Is dit goedkoper as om `n teleskoop te koop?
- Hoe maklik is dit om dit self te doen?
- Wat het jy alles nodig om so `n projek aan te pak?
- Waar kry jy al die benodigdhede vir so `n projek?
- Hoe slyp mens self die spieël?
- Het jy duur toerusting nodig om die voetstuk/basis te maak?
- Wie gaan help as jy vashaak?
- Hoe lank gaan die projek neem?
- Is `n selfgemaakte teleskoop beter as `n gekoopte teleskoop?

• As daar nog vrae is kan jy dit gerus vir ons stuur. e-pos aan: assabfn@gmail.com  Die kundige ouens sal dit Saterdagaand beantwoord.

Besoek ons 2007 webblad toe ons `n soortgelyke projek aangepak het en loer na die teleskope wat gebou is.

• Kliek hier
  

Daar is ook `n paar kort videos oor die slyp en bouproses van `n teleskoop.
Ons sal ook van die selfgeboude teleskope by Boyden hê, sodat jy kan sien hoe dit lyk. 
As die weer saamspeel sal ons ook deur `n selfgeboude teleskoop kan kyk.
Die kanse is goed dat jy al so `n teleskoop by Boyden op die platform gesien het.

Laat weet asseblief of jy die geleentheid gaan bywoon.
e-pos aan: assabfn@gmail.com