Derekscope

The Moon at apogee

• The Moon reaches apogee ~ the farthest point in its orbit from Earth.
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• The Moon appears slightly smaller and dimmer in the sky compared to perigee.
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• Lunar X and Lunar V
  Sunlight catches rims at lunar first quarter to create the bright V and X shapes.

• Best viewing time in the UK
  This is an evening twilight event for observers in the UK for British Summer Time (BST).
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  –…Today: Friday 18th September 2026
  –…Start formation: 18:15 / 6.15pm (become visible.)
  –…Peak visibility: 20:15 / 8.15pm (fully formed as best contrast.)
  –…Fade disappearing: 22:15 / 10.15am (The effect washes out as the sun rises higher over the lunar surface, removing the necessary shadows.)
  –…Visible: good (visible at evening twilight.)
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• The Moon repeats its cycle every 29½ days, so these effects happen every month, just on slightly different dates – see the complete full timetable for 2026, 2027, 2028, 2029 and 2030.
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• Equipment
  While sometimes visible with high-power binoculars, a telescope is recommended to see the fine detail of the crater rims forming the Lunar X and V.
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Venus reappearing from behind the Moon in a very low horizon event.

• This makes the reappearance harder to spot at first because of the bright glare from the Sun reflecting off the Moon’s surface.
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• Using binoculars or a small telescope helps observers track the exact moment the planet returns to view against the bright lunar.
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Minimum brightness times for Algol Minima

• Here’s a list of upcoming minimum brightness times for Algol (Beta Persei).
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• Read more – Algol
  – How to find Algol in Perseus?
  – Deaf astronomer John Goodricke
  

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Moon passes through the Beehive Cluster (Messier44)

• The crescent moon will appear a close approach and a partial lunar occultation of the Beehive Cluster (Messier 44 – Open Cluster) in the constellation Cancer.
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Close approach of the Moon and Mars

• You do not need a telescope!
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• Because they are spread out across a small gap (about the width of three fingers), they are perfectly framed for your naked eyes or a pair of binoculars.
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The Moon at Perigee

• The Moon reaches perigee ~ the closest point in its orbit from Earth.
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• The Moon appears slightly smaller and dimmer in the sky compared to perigee.
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Rising of Open Cluster Messier 35 with the Moon

• A Moon will pass very close to the open star cluster Messier 35 (M35) in the constellation Gemini.
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• The Moon and M35 will rise together in the north-eastern/East sky around 1:30 AM BST and will reach a prominent elevation in the pre-dawn hours.
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• Centre the crescent Moon in your binoculars ~ M35 will appear as a faint, shimmering spray of stars right in the same field of view.
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Minimum brightness times for Algol Minima

• Here’s a list of upcoming minimum brightness times for Algol (Beta Persei).
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• Read more – Algol
  – How to find Algol in Perseus?
  – Deaf astronomer John Goodricke
  

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• At the exact moment of Last Quarter, the Moon is in the constellation Taurus.
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• This is an excellent time to observe the 22 days old Moon (map) through binoculars or a telescope because the line between lunar night and day (the terminator) highlights craters and mountains with dramatic shadows.
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