Sunday, 2 August 2015

A Southern Comet in August - C/2013 US10 Catalina

C/2013 US10 Catalina (Click to Enlarge. Map created wit Skytools3

Source: Richard S Pearson

In 2013 we had comet ISON which put on a splendid display in the winter sky travelling along it's celestial path. ISON then embarked on a perilous journey towards the center of our solar system. ISON came to perihelion on 28 November of that year and broke apart due to the Sun's immense heat and tidal forces. That was the last we seen of this Christmas comet.
In the autumn of 2013 as comet ISON was putting on a display for amateur astronomers in the northern hemisphere, and the media were gearing up in preparation for a spectacular view of the comet in the first days of December, astronomer R. A. Kowalski identified a new comet; C/2013 US10 from images using a 0.68-meter (27 in) Schmidt–Cassegrain telescope of the Catalina Sky Survey.
C/2013 US10 Catalina was then at Mag +19 and very faint. It is a long period comet originating from the region of the Oort's Cloud with an orbital period of 7 million years. The Oort's cloud lies far beyond the orbit of Pluto.
Since then it has travelled in towards the Sun, and today (2 August) it lies 106,900 miles from the Earth, and is putting on a show for amateur astronomers living in the southern hemisphere. At the beginning of August comet Catalina is in the constellation of Tucana, and will pass through the adjacent constellation of Pavo from 8 -18 August, before moving through the constellation Apus during the end of the month.
During August the comet is easily within range of a pair of 10x50 binoculars. It is now shining at Mag +7.0 and will brighten to Mag +6.5 by 31 August.

Thursday, 9 July 2015

New Horizons Pluto Spacecraft Sends Photos As Excitement Builds for Flyby

Dwarf planet Pluto, shown here in the latest high-res image from NASA’s New Horizons spacecraft, will get its close-up in less than a week.

By Nadia Drake, National Geographic
PUBLISHED July 07, 2015

Pluto will get its closeup in less than a week, despite a heart-stopping glitch that briefly silenced the New Horizons spacecraft over the holiday weekend. Now, the craft is back in action and entering what NASA calls encounter mode—where gathering data about the frosted world trumps just about everything else.

Monday, 18 May 2015

Dunlop and Lacaille - Deep-sky Marathons at FS Star Party

The Guidelines for the two Deep-sky Marthons in progress....  The James Dunlop Catalogue (150 objects) and the Lacaille (1755) - Southern Nebulous Objects (41) are the two marathons on our deep-sky menu at the Free State Star Party (12 - 16 June 2015).

Visit the ASSA Marathon section

 Read more about the first ever marathon we have completed in Central South Africa in 2014 in Nigtfall.

 "Nightfall" (2015 April) is the current newsletter of the Deep-Sky Observing Section of the Astronomical Society of Southern Africa.
- Download the free PDF from the ASSA website at

Friday, 8 May 2015

Free State Winter Star Party - Vrystaat Winter Sterrefees

A Star Part in the warm heart of Central South Africa
12 – 16 June 2015

On the farm Gansvlei close to Brandfort (13km)
GPS Coordinates:  28°47'48.63"S   26°28'25.66"E

 Highlights at the FS Star Party
- Observing and Astrophotography
- Deep-sky Marathon
- A visit to Boyden Observatory (Museum and old telescopes)
- A show in the Digital Planetarium on Naval Hill.
- 3 Astro Guest Speakers

Vrystaat Winter Sterrefees
Sterpartytjie in die warm hart van Sentraal Suid-Afrika

Op die plaas Gansvlei by Brandfort (13km)
GPS Ko├Ârdinate  28°47'48.63"S   26°28'25.66"E

Hoogtepunte by die VS Sterrefees: 
- Waarneming en Astrofotografie
- Besoek Boyden Sterrewag met sy museum en ou teleskope

- Vertoning in die Digitale Planetarium op Naval Hill
- 3 Astro Gassprekers

Monday, 13 April 2015

First South African Comet Discovery in 35 Years


13 April 2015
First South African Comet Discovery in 35 Years

In the early hours of the 7th April, an un-manned robotic telescope, MASTER-SAAO, situated near Sutherland in the Karoo, discovered a new comet. This is the first comet to be discovered in South Africa since 1978.  The Russian – South African run telescope has been scanning the southern skies since it began operating in late December 2014, looking for “transients” – new objects which appear in the sky for the first time. Since then, over 60 new  objects have been discovered, most of them being erupting or exploding stars. However, the MASTER-SAAO telescope has just discovered its first comet.

Read more about this discovery 

Sunday, 29 March 2015

DSLR Photometry Experiments. 4. How many darks?

When performing photometry on DSLR images, should dark frames be stacked and subtracted from the light frames? If so, how many dark frames should be used, and which stacking method should be employed? This experiment attempts to answer the first question by evaluating the signal-to-noise ratio (SNR) of stars on an image from which different numbers of dark frames have been subtracted.