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Posts by
Guy Ottewell
Constellations and signs: What’s the difference?
What is the difference between signs of the zodiac and constellations of the zodiac? Astronomer Guy Ottewell illustrates and discusses this difference.
June 3, 2025
A superb Venus inferior conjunction by Guy Ottewell
Venus will pass between Earth and the sun on March 22-23. You might be able to see Venus in both the morning and evening twilight for a few days before then.
March 18, 2025
What is the equation of time? And what is noon, for you?
The difference between apparent solar time (the actual time between noons) and mean solar time (the average time between noons) is called the equation of time.
June 18, 2024
Tonight’s young moon emerges into the evening sky
The young moon will compete in brightness with several bright stars on the evening of May 9, 2024. Which will shine most brightly?
May 9, 2024
Penumbral lunar eclipse to pass quietly March 24-25, 2024
The 1st of this year's 4 eclipses will flit by like a ghost in the night between March 24 and 25. It's a penumbral lunar eclipse, visible in North America. Charts and more from Guy Ottewell here.
March 24, 2024
Jupiter and Uranus meet in the sky
Jupiter and Uranus will be at heliocentric conjunction on March 14. Their conjunction as seen from Earth will be on April 21.
March 14, 2024
Observable comets in 2024, from Guy Ottewell
Here are predictions from Guy Ottewell for the observable comets in 2024. C/2023 A3 Tsuchinshan-ATLAS might be a bright comet in October.
January 18, 2024
Sky trio for you, Southern Hemisphere friends
Here's a chart showing a delicate sky trio - as seen from Australia and New Zealand - on the evening of November 15, 2023. Look soon after sunset!
November 14, 2023
Where is Proxima Centauri?
The closest star to our sun is Proxima Centauri, in the triple star system Alpha Centauri. But where is Proxima Centauri in our sky and in space?
October 26, 2023
Solar eclipse in 2077 almost repeats last Saturday’s eclipse
Another annular solar eclipse - similar to the one on October 14, 2023 - will visit almost the same geographical region in 2077.
October 17, 2023
