Monday 11th to Sunday 17th October 2021
Last week we talked about the phases of the Moon and I mentioned trying to see a dimly-lit Crescent Moon. Now, further into the Moon's 29-day cycle, there is the chance to see a 67%-lit waxing Gibbous Moon on Thursday 14th October.
If you look to the south around 8pm local time, the Moon forms a triangle with Jupiter and Saturn. The pair of gas giant planets is well-placed at the moment for observations with a telescope.
When observing the Moon, there are a series of visual effects known as "clair-obscur" originating from the French words meaning "light" and "shadow". The interplay between sunlight falling on the lunar surface and your viewing angle creates easily-recognisable shapes.
If you aim your telescope towards the giant crater Clavius on Thursday 14th from about 7.30pm, you can see an effect known as the "Eyes of Clavius". It looks like a pair of eyes staring out of the crater!
I've provided a diagram of the different clair-obscur effects and an image showing the Eyes of Clavius, courtesy of Sky at Night Magazine.
The diagram makes it easy to find Clavius, but please remember that if you are using an astronomical telescope rather than standard binoculars, everything will be upside down and back to front because there is no extra lens correcting the image!
Screenshot courtesy of Stellarium
Copyright Adrian Dening and Radio Ninesprings 2021
Adrian Dening's Stars Over Somerset
Improved Transport Links
Courier Fraud
Wheelie Bins
Bus Route Changes
False Fire Alarms
Dog DNA
