Blackett Observatory Dome
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Marlborough College
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NASA Astronomy Picture of the Day
From Alpha to Omega in Crete

What's Up - Week of 27th June

  • The Moon is Last Quarter on Monday and will wane to New at the start of next week

  • 3 naked-eye planets are visible in the evening sky after sunset with Jupiter appearing bright yellow in the West in Leo and Mars bright redish in SSE in Libra. Saturn is yellow and a little dimmer and to the East of Mars in Ophiucus. Below Mars, closer to the horizon is red Antares (in Scorpio). Arcturus is high in SW and if you follow the arc from the handle of the 'saucepan' down you reach blue Spica (alpha Virgo)

  • The Sun is still blank after 4 days and activity is very low

  • The ISS makes no evening passes this week

  • There is one superbright evening Iridium flare this week on Monday at 21.48.58 at 38 degrees altitude in NE


Random Blackett Image
The 2004 October Lunar eclipse, when the Earth's shadow cuts off sunlight from the face of the full Moon. The red colour is due to refraction of sunlight through the Earth's atmosphere, effectively a projection of all the sunsets on Earth. (Venturin)

News - 18th June

Solstice observing: A small group of Friends gathered in the summer twilight to watch 3 planets appear. Despite the nearly Full Moon, Mars shone brightly in the South and Jupiter in the West. Saturn was rather close to the Moon and dimmer. Red Antares twinkled in the thick lower atmosphere with blue Spice in the South West. The Moon was observed in the ETX and then Jupiter. The 10 inch tracked Saturn as as the sky darkened first Tutan then Tethys then Dione appeared. A good Summer Sky tour was also possible.

9th May

Transit of Mercury: The first of the pair of Transits this decade took place amid very poor weather forecasts. Just on the off chance of a glimpse, CEB and JAG went to open the Dome at noon and were joined by a small groupd of Friends and visitors. Extraordinarily around 12.05 BST the sky largely cleared by high cloud. The 10inch had sufficient light gathering to give a cler view of the photosphere. Seeing made the limb wobbly, but using a radio controlled clock the moment of First contact was seen about 10 seconds late. As the planet moved onto the disc there was a clear 'dragging' on the black of space behind it (like a pool with an outflow) giving an indisputable 'black drop effect' which lasted a while and was drawn by eye at 11.15.28 UT. Second contact was observed with a narrow arc of light between the planet and the limb at 11.15.31 UT (fractionally before the time predicted). The perfect black dot moved on across the disc and more Friends joined joined to see it between clouds. By 1pm the clouds and then rain ended the observations

5th April

BAAO training camp: CEB spent a day in Oxford on day 2 of the 4 day British Astronomy and Astrophysics Olympiad training and UK team selection camp (12 yr12 and yr13 pupils being narrowed down to a team of 5 and a reserve for the 2016 International Olympiad on Astronomy and Astrophysics in India in December). CEB ran a planetraium session, gave a lecture on Telescopes and Optics followed by some questions and then in the evening oversaw an observing session on level 6 of the Denys Wilkinson Building. 2 ETX 105 Meades were available as well as a small Newtonian and a huge 12 inch Meade (brough by Alan Pickwick). The sky was largely clear and, though the view was restricted by the buildings, Jupiter and its moons were viewed (with Europa and Io in conjuction and visibly seperating over the 2 hours of observing) and Mizar and Alcor (with Mizar A and B resolved) and then h and k Persei, the Double Open Cluster. Individual stars were also identified and pointer patterns discussed

24th March

Sun-Earth Lecture: The 14th lecture focussed on the Vernal Equinox and tackling subjects within the basic field of Sun-Earth connections 'Transits an Occultations - the importance of shadows' was delivered to an audience of some 40 Friends and visitors by CEB

19th March

Friends outing: A group of 20 Friends headed to Oxford for visits in the Astrophysics sub-department. A talk on the E-ELT and Oxford contribution to major instruments by Dr Fraser Clarke and tours of the Instrumentation labs. After lunch the group were met by Proffessor Jeff Burley in Green Templeton College for tours of the Tower of the Winds and the old Radcliffe Observatoy

13th March

House visit: The last Shell House visit of the academic year took place with 7 pupils from PR coming up to the Dome. The temperature was falling and the sky very clear. There were also no Astro lights so the conditions were perhaps the best so far since January. The 4 day old Moon was viewed in the ETX and M45 in the Binos. Jupiter shone brightly in the ESE and was viewqed very well in the 10 inch with Europa and Ganymede very close and several storm bands on he planet seen

12th March

Spring Sky: A small group of Friends and visitors, including a family from Oxford and a yr 6 and yr 8 pupil, came up to the Dome. Depsite mist and hazy cloud the 3 day old Moon was viewed in the James ETX and the Pleiades in Binos. The ETX was used for M42 the Orion Nebula earlier. A tour of the sky was given including the Zoiac constellations. The 10 inch tracked Jupiter and its 4 moons. 2 main bands and 2 subsidiary bands were visible on the main planet

8th March

House visit: 9 pupils from C1 Shell came up to the Dome. It was cloudy

Last House visit of the academic year: Sunday 13th March (PR)

6th March

House visit: 7 pupils from CO Shell came up to the Dome. One or two stars were visible in cloud gaps; only Sirius identifiable

Next House visit: Tuesday 8th March (C1)

28th February

House visit: An even better clear night greeted 14 MM Shell. The Pleiades ere viewed in Binos and Jupiter and 4 moons in ETX. The 10 inch showed good detail of M42, the Orion Nebula and the Trapezium

Next House visit: Sunday 6th March (CO)

23rd February

House visit: At last a clear night and LI Shell drew the lucky card. 8 pupils came up to the Dome. The sky was bright with the waning just off Full Moon beutifully in conjunction with Jupiter less than 2 degrees away. The Binos were used to view the pleiades and the ETX Jupiter and 3 moons (Io in Occcultation) The 10 inch tracked M42 (Orion nebula) and gave a super viw of the Trapezium and good detail in the nebula itslef. The bottom right star inthe Trapezium could just be resolved into two

Next House visit: Sunday 28th February (MM)

GCSE Observing: The last chance for Coursework to be completed by Hundreds. With CEB, NMA and DGR at the Dome, 6 pupils came up to complete stellar density and Messier drawings and photographs. All the instruments were used, Binos, 2 ETXs and the Smith Newtonian. Several Remove also came up to fisnish Constellation drawings , using Orion and Cassiopeia. Io was seen to appear from occultation and the Spring marker, Arcturus, rose in the East. A close call, we have never had to wait to so near March to complete observations

10th February

GCSE Obsertving: At last a clear night and an emergency observing session with 5 out of the 6 Hundred pupils joining NMA at the Dome to complete drawings

7th February

House visit: 14 Shell pupils form EL came up to the Dome in rain and high winds, having been out climbing during the day. One of the most miserable evenings but lots of good questions

Next House visit: Tuesday 23rd February (LI)

31st January

House visit: 10 pupils from TU Shell came up to the Dome in high winds but at least no rain

Next House visit: Sunday 7th February (EL)

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