Friday Night (25 Januarie 2013) C/2012 F6 (Lemmon)

Friday - About 23:30 to be precise. I spent some time to find Comet Lemon with my 10X50 binoculars. With the help of my Skytools map it and the binoculars steady on a tripod it was easy. Even with the almost full moon and some street lights. A black cloth over your head will also help. 

The techno info the same: Canon 30D with a 300mm (X1.6) lens. 10 Seconds with ISO 3200. I used  Nebulosity software ( Stark Labs) to prepare the image.

• Map for tonight 
• Long term map - Tonight - 10 February

Compare with the original RAW image below.

And the final image without the text.

Comet Lemmon (C/2012 F6) 23 Januarie 2013

Click to enlarge

With Crux on the left and Musca to the right, Comet Lemmon (C/2012 F6) on the late night 23 Januarie 2013 is a little green spot. Photo: Hannes Pieterse

Info: Canon 30D with 50mm lens; 20 X 15 sec exposures; ISO 1600, f4. 20 X Dark frames. Images were prepared in Deepskystacker > Separate registered and dark frame subtracted images were created.  These were stacked in Rot`nStack. Final image was tweaked in Photoshop.

- A tree interfered on the right 

For the Bibliophiles: Deep-Sky Companions: Southern Gems

Hot off the Press!

Deep-Sky Companions: Southern Gems - Stephen James O'Meara

In Southern Gems, Stephen James O'Meara makes a detour beneath the southern skies, presenting a fresh list of 120 deep-sky objects for southern hemisphere stargazers to observe. Showcasing many exceptional objects catalogued by the pioneering observer James Dunlop, known as the 'Messier of the southern skies', all are visible through small- to moderate-sized telescopes or binoculars under dark skies. The list features some of the blackest dark nebulae, icy blue planetary nebulae and magnificent galaxies of all types. Each object is accompanied by beautiful photographs and sketches, original finder charts, visual histories and up-to-date astrophysical background information. Whether you live in the southern hemisphere or are just visiting, this new Deep-Sky Companion will make a perfect observing partner, whatever your background. There is no other southern sky guide like it on the market.

• Magda Streicher a southern observer from Polokwane also contributed to make this book a must have!   

• Publisher: CAMBRIDGE UNIVERSITY PRESS 
• Published: 31 January 2013 
• Hardback
• ISBN:9781107015012
• 450pages
• 204 b/w illus. 114 maps
• Dimensions: 253 x 177 mm

- Search inside the book - Amazon
-The Book Depository (Free Shipping to South Africa)  - $40.80  (Best Price)

From Bloemfontein: Comet Lemmon (C/2012 F6)

22 January 2013 - Moves into Constellation, Musca (23:00) In spite of the moon and other lights the comet is still clearly visible
January 21, 2013 - Near Acrux, Constellation Crux

For the night owls: Comet Lemmon (C/2012 F6) is clearly visible. Bright star on the image is Alpha 2 Cru (Acrux).

Technical data: Canon 30D with 300mm X 1.6 lens. ISO 3200; Aperture f5.6 Shutter speed 5 seconds. Camera on tripod. 15 photos stacked on each other in Deepskystacker; 10 Dark frames used to remove digital noise. It is also easy visible with a 12X50 binoculars. Even better with a 20X80 binoculars. The light pollution is quite bad in Bloemfontein and the moon was still up. Despite this I found it easily. According to Skytools 3 it is magnitude 7.2.

A look or you see it tonight and let you know.

•   Star chart created with Skytools 3 to locate the comet.

Comet Lemmon (C/2012 F6) brightens faster than expected

 Comet Lemmon (Michael Jaeger)

In Crux
2013 is gearing up nicely to be a superb year for bright comets. Already we have two comets that promise to be spectacular this year; Comet PanSTARRS (C/2011 L4) should peak at magnitude -1 in March and then later in the year comet ISON (C/2012 S1) may even reach the dizzy heights of magnitude -15 in November.

There is another comet that is currently brightening faster than expected and although will probably not be bright as the above-mentioned comets, it may prove to be the surprise package of the year. Its name is Comet Lemmon (C/2012 F6).

Discovery
Alex Gibbs of the Mount Lemmon Survey discovered Comet Lemmon on March 23, 2012. The Mount Lemmon Survey is part of the Catalina Sky Survey (CSS), a Near-Earth objects searching project, specifically aimed at finding potentially hazardous asteroids (PHAs) that may pose a threat of impact to Earth. Currently there are a number of telescopes participating in the survey, each of the order of 1-metre in aperture, located at various astronomical sites. The project is producing superb results with the Mount Lemmon telescope currently the most prolific telescope in the world for discovering Near-Earth Objects.
The objects discovered are often faint; Comet Lemmon was only magnitude 20.7 when found.

More information...

Polish your metal mirror - Sir William Herschel

This is an example of a polishing machine devissed by William Herschel for small speculum metal mirrors. Image: Herschel Museum of Astronomy, Bath 

For your book shelve

From: The Complete Guide to the Herschel Objects: Sir William Herschel's Star Clusters, Nebulae and Galaxies - by Mark Bratton

• Amazon

•  Herschel Museum of Astronomy  

• Herschel Museum of Astronomy (Wikipedia)

Near-Earth Asteroid 2012 DA14 to Miss Earth on February 15, 2013

In this oblique view, the path of near-Earth asteroid 2012 DA14 is seen passing close to Earth on Feb. 15, 2013. 

Discovered by the LaSagra observatory in southern Spain, the small asteroid 2012 DA14 will pass within about 3.5 Earth radii of the Earth's surface on February 15, 2013. Although its size is not well determined, this near-Earth asteroid is thought to be about 45 meters in diameter. Asteroid 2012 DA14 will pass inside the geosynchronous satellite ring, located about 35,800 km above the equator. Its orbit about the sun can bring it no closer to the Earth's surface than 3.2 Earth radii on February 15, 2013. On this date, the asteroid will travel rapidly from the southern evening sky into the northern morning sky with its closest Earth approach occurring about 19:26 UTC when it will achieve a magnitude of less than seven, which is somewhat fainter than naked eye visibility. About 4 minutes after its Earth close approach, there is a good chance it will pass into the Earth's shadow for about 18 minutes or so before reappearing from the eclipse. When traveling rapidly into the northern morning sky, 2012 DA14 will quickly fade in brightness.

Source: NASA

Sunspot AR1654 (12 January 2013)

 Photo: Dennis Simmons, Brisbane, Australia

Since it first appeared four days ago, sunspot AR1654 has been facing away from Earth. But now it is turning toward us, increasing the "geo-effectiveness" of its explosions. This could be the sunspot that breaks the recent lengthy spell of calm space weather around our planet.

Amateur astronomers with backyard solar telescopes are encouraged to monitor in the days ahead. It is not only crackling, but also growing. As of Jan 12th, the behemoth stretches more than 180,000 km (14 Earth diameters) from end to end. Dennis Simmons sends this picture of the behemoth from Brisbane, Australia: "Although the air was milky from nearby bush fires burning north of Brisbane, the seeing turned out to be good enough for a high-resolution shot," says Simmons. "I dedicate this image to the brave Australian fire fighters, working in horrendous, hot and windy conditions whilst fighting fires burning out of control across the south-east states of our country. I salute your selfless courage."

Visit: Spaceweather.com

AR1654 is a Monster Sunspot. (And It’s Aiming Our Way.)

• Read more

 Active Region 1654 on the Sun’s western limb, seen by SDO on Jan. 11 (NASA/SDO/HMI team. Diagram by J. Major.)

Sir Patrick Moore death: Tributes to the astronomer

Sir Patrick Moore's contribution to the world of astronomy

• Visit this page for a tribute to this remarkable man

Orion vanaf Boyden-sterrewag

ASSA Bloemfontein het `n mini werkswinkel oor "Wyeveldastrofotografie met `n DSLR-kamera op `n driepoot gehou. Barbara Cunow se lesing by die Kaapse simposium het as grondslag gedien.

Daar is so bietjie afgewyk van die lesing, maar die basiese beginsel was dieselfde.

Verloop van die lesing:

Kyk eers na die YouTube-video en bespreek dit.

•  Doing astrophotography with a DSLR on a tripod, presented by Barbara Cunow
  
  - YouTube

Basiese stappe.
1. DSLR-kamera (Weet hoe werk die Self Timer om die kamera eers te stabiliseer; (of `n elektroniese sluiterontspanner). Gebruik die kamera op Manual; Fokus ees op helder ster of planeet en skakel dan outofokus af.
2. Stewige driepoot
3. Hoë ISO  1600 en 3200
4. Kort beligtings 4 sekondes tot so 10 sekondes  werk goed in ligbesoedelde omgewing
5. Lens: 18 - 55mm en 100mm
6. Beligtings: 10 - 480

Sagteware.
1. Barbara eveel Regim aan om fot's op mekaar te pak (stack).   (Laai af)  Jy het die jongste Java Script-sagteware nodig en laai Regim af met 64 bit Internet Explorer). Unzip en dubbelkliek op regim.cmd.

2. Ons het Deepskystacker gebruik (DSS) (Laai af)

   - YouTube-video om Deepskystacker te gebruik
   -  Nog een wat by vorige aansluit (met aanpassings)


Die les wat ons uit die lesing geleer het is om dinge eenvoudig te hou.
Hierdie is die begin van jou eerste treetjies om astrofotografie te doen.

Bietjie afdwaal. 
Johan Smit van Pretoria het vroeër vanjaar by die Karoo-sterrefees `n eenvoudige formule gegee om met jou ISO en die fokale lengte van jou lens die regte sluiterspoed uit te werk sonder om sterstrepe (startrails) te kry.

Hierdie formule kan veral in `n donker  omgewing werk en `n goeie riglyn wees. Eksperimenteer gerus daarmee.  Hier is `n webtuiste waar dit bespreek word.  ( Tips > Stars & Star Trails ).  Barbarahet haar foto's in `n ligbesoedelde omgewing geneem.

Di. ISO ÷ Focal Length = Maximum Shutter Speed

- Onthou die goedkoper DSLR-kameras het `n X1.6  faktor.

- Vir hierdie kameras is die formule:  ISO ÷ (Focal Length X 1.6) = Maximum Shutter Speed
 Voorbeeld:  3200 ISO ÷  (24mm X 1.6) = 83 sekondes.

  Vir `n plek met baie ligbesoedeling sou jy hierdie formule kon aanpas. Stel op 400 ISO en `n 10 sekonde beligting is die gevolg.  Dit gaan jou so `n bietjie eksperimentering kos.

Groete
Hannes Pieterse
(assabfn@gmail.com)