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Marlborough College
Oxford Astrophysics
Green Templeton College

Summer School week 3: Wednesday 25th July: Observing (weather permitting). Sign up list in Summer School office.

Total Lunar eclipse: Friday 27th July. The observatory will open from 9pm

NASA Astronomy Picture of the Day
Planck Maps the Microwave Background

What's Up - Week of July 23rd

  • Astronomical twilight at last comes to an end and true darkness returns, all be it briefly. At the start of the week it gets dark at 00.29 BST and 23.52 BST at the end

  • The Moon is waxing and will be Full (Thunder Moon) on Friday, when it passes into the Earth's shadow. The eclipse is Total and very long, lasting for over 6 hours (given the Moon is at apogee, it will be the longest in the 21st Century). The Moon rises already in the umbra and should be a deep red colour at 21.05 in SE. Totality starts to end at 21.45 with the Moon at only 5.5 degrees altitude. The Moon is fully in the penumbra at 23.00 at 13 degrees altitude. Full brightness will have returned by 00.45

  • The Sun has one inactive spot

  • Four planets are visible during the evening. Venus dominates the West and sets around 10pm. Jupiter is highest in the South, followed by Saturn. Mars rises just after 22.00 and is only 5 degrees from the Moon, slightly to the South at 11pm

  • The ISS makes excellent long and high passes this week: The best is on Monday at 23.21.31 from W to E passing through the Zenith at 90 degrees. Tuesday at 22.29.24 from WSW to E reaching 77 degrees. Wednesday at 23.13.44 from W to E reaching 84 degrees. Thursday at 22.21.33 from W to E reaching 87 degrees and 23.58.04 W to SE to 74 degrees. Friday at 23.05.53 from W to E reaching 88 degrees. Saturday at 22.13.41 from W to E reaching 85 degrees and 23.50.12 from W to SSW to 50 degrees and Sunday 22.57.59 from W to ESE reaching 68 degrees

  • There is one bright evening Iridium flare this week on Thursday at 23.22.44 at 22 degrees altitude in NNE


Random Blackett Image
The innermost of the Galilean moons of Jupiter, coloured due to its sulphurous, volcanic surface, crosses in front of the parent planet, preceded by its sharp black shadow. (NASA, Hubble)

News - 18th July

Summer School week 2: Some 30 Summer School gueest joined CEB, JAG, DGR and GKWJ at the Dome under clearing skies. Venus was seen in the twilight and then Jupiter (first with 3 moons and then with IO appearing from its shadow) in the 10 inch, then Saturn with Titan and finally Mars, which showed more detail than last week and a discernable bright ice cap. The ETx and various binoculars were used outside to view the Moon, M13 and M31 and to split Mizar. A couple of metors were seen, but we missed the low ISS pass

14th July

Impromptu observing: GKWJ and JAG hosetd a small group of six visitors at the Dome under excellent clear moonless skies and good Seeing. The 10 inch viewed Jupiter and its four Galilean moons, Saturn and possibly five of its moons, a dusty featureless, but bright and very red Mars, double star Albireo, M57, the Ring Nebula, M56, a Globular Cluster in Vulpecula and M27, the Dumbbell Nebula. An OIII filter was used with M27 and it definitely improved definition of the shape (a sheaf of wheat). The summer constellations and the Milky Way were good with naked eye outside and M31 and the Double Cluster through binoculars. A large number of meteors were seen throughout the evening. Five meteor shower radiants are close together near the southern horizon around midnight; Southern Iota Aquariids, Southern Delta Aquariids, Piscis Austrinids, Alpha Capricornids and June Scutids. All have their maxima later this month

11th July

Summer School week 1: CEB was joined by JAG, DGR and GKWJ at the Dome under clearing skies for group of some 20 Summer School guests. Bright stars were spotted as they appered in cloud gaps and then in improving conditions Jupiter and 4 moons was viewed in ETX and Binos and in the 10 inch, which showed some colour on Io and 4 bands on the planet. The 10 inch then moved to Saturn and not only was the Casini Division well defined, but 4 moons were visible. After most visitors had gone the 10 inch moved to view the Double binary in Lyra. As we left the Dome bright red Mars was rising and was viewed as a bright disc in the ETX

27th June

External visit: A small group of friends from Oxford were followed by a Norwegina Reuters' Fellow and colleague from Oxford University. Both groups had clear skies and super views of the Sun through goggles, in the SolarScope and ETX and in H alpha in the 10 inch. A huge triangular shaped prominenece was seen in good detail

24th June

External visit: A small group from London came to the Dome for an afternoon of solar observing. The Photosphere was viewed in goggles, projection box and ETX (where spot group 2715 was easily visible) and then the Chromosphere with several active regions in the 10 inch

21st June

Solstice observing: JAG and GKWJ joined CEB and a small group of Friends to see out the Solstice. The night was warm and clear and as the sky darkened, there were plenty of targets to observe, including a bright Iridium flare. The Moon was viewed in the ETX and the 8 inch Smith and Binos. Venus showed its 70% illuminated phase in ETX. Jupiter and 4 moons were seen in ETX then Smith then 10 inch, with Io and Ganymede overlapping. The 10 inch then moved to Saturn, very orange and low on the horizon, then Antares in search of Antares B. Some thought there was a little assymetry in the twinkling star. Vesta was then well veiwed as a steady disc. M10 was too faint to see detail but M57 was clear. Saturn was viewed again with both Titan and Rhea now visible. The evening ended just before midnight with a viedw of Albireo, such a beautiful bi-coloured double of the blue B8 and yellow K2 stars

19th June

Wetton Workshop and lecture: CEB attended the official opening of the Roswitha Wetton Telesope (RWT), a new 2 radio dish interferometer on the roof of the Denys Wilkinson Building. Following the unveiling a lecture on Exoplanet discoveries was delivered in the Martin Wood lecture theatre and then dinner in Christ Church

14th June

External visit: In the last Swindon Academy group visist, 11 year 10 girls and their teacher came up to the Dome. The Sun was viewed in goggles between clouds and in the projection box and then in the ETX. The 10 inch showed a couple of prominences on the southern limb in H alpha

13th June

External visit:12 year 7 girls and their teacher from Swindon Academy came up to the Dome. The sky was cloudy

12th June

External visit: 22 year 7 pupils and 2 teachers from Swindon Academy came up to the Dome as part of their stay at the College. They were accompanied by a postgrad from Imperial College and undergrad from Birkbeck. The sky was sadly cloudy

Observing evening: The two University visitors joined GKWJ and JAG at the Dome as the sky had cleared for a tour of the sky with the 10 inch. Jupiter and its moons, Vega, Albireo, M13 and Saturn, still rather low to the horizon, were viewed

17th May

Solar open day: Under sunny skies but sadly increasing high cloud, the Dome opened to public, Friends and College staff. The Sun was viewed in solar goggles, the projection box and the ETX in white light and a dedicated small solar refractor and the 10 inch in H alpha. Despite a totally blank disc, reflecting the minimum in the solar cycle, there was a decent quiescent loop prominence visible in H alpha when the sky was clear enough. JAG and GWJ helped CEB welcome families, Friends and staff from 3 yrs and up

30th April

Lunar imaging: GKWJ attempted a mosaic of the lunar surface at the Full Moon. Despite clear patches, the Seeing conditions were poor

21st April

GCSE Solar observing: Remove set 1 came up to the Dome under clear if hazy skies. The Sun was viewed in goggles then via projection and in the ETX, where the faint spot 2706 was seen. The H-alpha filter on the 10 inch showed no activity due to the poor clarity

19th April

GCSE Solar observing: Remove set 2 came up to the Dome in hot sunshine as part of Topic 11 and the Sun's surface. The Sun was viewed in goggles, via projection and the ETX the blank photosphere in white-light and then the 10 inch showed a couple of Chromosphere prominences in H-alpha

18th April

GCSE Solar observing: The Hundred Astronomy set came up to the Dome in their afternoon lesson under clear skies. The Sun was viewed in goggles, projection box, ETX and white-light filter and then despite no sunspots, there was activity in the form of an erruptive prominance and quiescent prominance in H-alpha through the 10 inch

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