Derekscope

Moon forms a triangle with Castor & Pollux

• The waning crescent Moon will serve as the bottom anchor of the triangle, with the pure white star Castor to the upper left and the brighter, golden-hued giant star Pollux to its right.
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• The triangle will be beautifully positioned in the early morning sky around 2am – look toward the east-northeast horizon.
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Last Quarter Moon

• 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.

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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Moon rises with the Seven Sister (Messier 45)

• The Moon will be in a waning gibbous phase (86% illuminated), meaning its intense glare will wash out some of the faintest stars in the cluster.
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• Binoculars will help you cut through the moonglow to reveal dozens of additional blue-white stars in the group.
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• For observers in the UK and Europe, the pair will clear the horizon in the late evening of Tuesday 29th and put on their best display high in the sky through the early morning hours of Wednesday 30th September.
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A simple smartphone capture, showing that you can enjoy the night sky with whatever camera you have.

• According the Derekscope’s highlight (Sat 26th Sept):
  Mars in a line with Castor & Pollux.

• According the Derekscope’s highlight (Sun 27th Sept):
  The Moon Passes Saturn.

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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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The Moon passes Saturn

• The Moon will pass very close to Saturn on Sunday 27th September 2026.
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• The two celestial bodies will share a close conjunction in the constellation Cetus, which will be highly visible in the night sky over both on Sunday 27th and Monday 28th of September.
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Mars in a line with Castor & Pollux

• Look toward the East-North eastern horizon.
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• The bright twin stars of Gemini rise just slightly later, with Pollux rising at approximately 02:00 am BST.
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• All three objects ~ the best viewing window is during the early morning hours just before dawn.
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• Facts about three celestial objects;
  
  Mars – the red planet shines with a distinct reddish-orange glow due to iron oxide on its surface.
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  Pollux – the brighter of the two Gemini twins, Pollux is an orange giant star with a warm golden hue.
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  Castor – a multi-star system that appears as a whiter, slightly dimmer companion next to Pollux.
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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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Autumn Equinox

• Equal Day and Night
  – The word equinox actually means “equal night.”
  – On this day, you get about 12 hours of daytime and 12 hours of nighttime.
  – It is a perfect 50/50 split!
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• On the September Equinox
  – The Sun crosses the Earth’s equator line.
  – It is right in the middle of the seesaw.
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• After September (Autumn & Winter)
  – The Sun “joins” the Southern Hemisphere (places like Australia and South America).
  – They get to enjoy their spring and summer, while our days in the Northern Hemisphere get shorter and darker.
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