Around The Sea of Moisture - Gibbous Moon Watching Part 3

Around The Sea of Moisture - Gibbous Moon Watching Part 3

In this final part on what surface features to look for on the moon when it is a waxing gibbous moon we'll take a tour around The Sea of Moisture. This is an easy to identify mare towards the bottom of the moon. It has two almost like rabbit ear protrusions coming out of the northern part of the mare to help you to identify it. It is number 3 on the image below. 

The Gibbous Moon

gibbous moon

Click the image to enlarge

The images here are orientated as if you are looking straight at them with the naked eye.

Once you have found the Sea of Moisture (Mare Humorum) then zoom in with your binoculars or telescope to take the tour below.

Around the Sea of Moisture Tour

Sea of Moisture

Click the image to enlarge

1. Sea of Moisture (Mare Humorum)

This is a very nice sea to spend some time looking at. You'll notice some small craters dotted around inside it and towards the eastern edge there are some wrinkles in the floor. These can be hard to see as they only rise a few tens of metres above the sea floor. The best time to catch them is when the sunlight is just crossing the sea.

2. Shickard Crater

This crater is 227km across making it one of the biggest craters on the moon. It is an old crater that has been flooded with lava several times. This gives it an unusual and striking mottling tonal change to its floor. See how many small craters you can count within its boundaries. You are doing well if you spot five.

3. Nasmyth Crater

This crater makes up a chain of three, the other being Phocylides and the one nearest to Shickard is Wargentin. Wargentin isn't on show in the images above but is a good crater to look for as it is filled to the brim with lava but appears to be the youngest of the trio of craters in this chain.

4. Phocylides Crater

This crater is 114 km wide. It forms part of the trio of craters described above.

5. Gassendi Crater

This is a fabulous old crater. It is almost circular and contains a fractured floor. This can be seen when the sun is casting long shadows in the crater's basin. There are numerous mountains to be seen in the crater rising up to 1000 metres. The crater is 110 km across and the wall rises to 3,600 metres. Look for the Gassendi A crater that cuts the northern part of the main parent crater. This crater was considered to be the landing site for the last mission to the moon, Apollo 17. Although it offered the highest scientific returns it was turned down due to the difficult landing terrain surrounding the landing site.

6. Mersenius Crater

This crater is interesting as it has a convex (bending upwards) floor. This is evident by the shadows that are cast across the floor.

7. Cavendish Crater

This crater is 56km across and if you look carefully you can see two almost buried craters that are joined at the rims.

8. Vieta Crater

See if you can spot the chain of small craters in the northern part of this crater's floor.

9. Sirsalis and Sirsalis A

These two craters form a very distinctive pattern in the way they overlap each other. Just to the east of these is the Rimae Sirsalis. This network of valleys can be a challenge to follow. You can pick up the 330km main valley (named rilles on the moon) as it passes just a few kilometres from the south-eastern edge of the Sirsalis crater.

I hope you enjoyed these three posts on what to see on a gibbous moon. Please leave a comment about your experiences. Many thanks.

Related Posts: Full length, Observing

Around Imbrium - Gibbous Moon Watching Part 1

Around Copernicus - Gibbous Moon Watching Part 2

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