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Community amateur astronomy education, promotion, and observation.

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Welcome to Prince Edward Island's only astronomy club.
Join us and explore the universe with us!
 

Daily Astronomy Blurb:
Two Worlds, Two Analemmas

Sure, that figure-8 shaped curve you get when you mark the position of the Sun in Earth's sky at the same time each day over one year is called an analemma. On the left, Earth's figure-8 analemma was traced by combining wide-angle digital images recorded during the year from December 2011 through December 2012. But the shape of an analemma depends on the eccentricity of a planet's orbit and the tilt of its axis of rotation, so analemma curves can look different for different worlds. Take Mars for example. The Red Planet's axial tilt is similar to Earth's, but its orbit around the same sun is more eccentric (less circular) than Earth's orbit. As seen from the Martian surface, the analemma traced in the right hand panel is shaped more like a tear drop. The Mars rover Opportunity captured the images used over the Martian year corresponding to Earth dates July 2006 to June 2008. Of course, each world's solstice dates still lie at the top and bottom of their different analemma curves. The last Mars northern summer solstice was May 29, 2025. Our fair planet's 2025 northern summer solstice is at June 21, 2:42 UTC.
© apod.nasa.gov

ACAC News

Athena Community Astronomy Club

Upcoming Events

Monthly Meeting
Monthly Meeting
Jun 29, 2025
7:00 pm - 9:00 pm
Monthly Meeting
Monthly Meeting
Jul 27, 2025
7:00 pm - 9:00 pm
Monthly Meeting
Monthly Meeting
Aug 31, 2025
7:00 pm - 9:00 pm

Past Events

Monthly Meeting
Monthly Meeting
May 25, 2025
7:00 pm - 9:00 pm
Monthly Meeting
Monthly Meeting
Apr 27, 2025
7:00 pm - 9:00 pm
Monthly Meeting
Monthly Meeting
Mar 30, 2025
7:00 pm - 9:00 pm

Recent News

  • Every amateur astronomer knows the name, many have his books. Probably the last…
  • It’s SUMMER! Yeah, that means suspension of our regular monthly meets, but not u…
  • Moon over Searletown. Time slides on. Cloud feces.
  • Cloudy, cloudy eve. Sidewalk astronomy not likely. It’s not that we don’t want…
  • Monthly Meeting reminder: Sunday, 26 May, 7- 9p.m. @ Wilmot Community Centre (Gi…
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