November’s top lunar feature to observe
Hainzel
Type: Crater
Size: 70km
Longitude/Latitude: 33.5˚ W, 41.2˚ S
Age: Around 3.9 billion years
Best time to see: Three days after first quarter (4 November) or two days after last quarter (18–19 November)
Minimum equipment: 50mm refractor
You could sum up crater Hainzel by saying it’s large, easy to find but difficult to see. Let’s address these in order. With a diameter of 70km, Hainzel is certainly big, just 16km smaller than the bright ray crater Tycho that is located 500km to its east. Then there’s the fact that finding Hainzel is easy due, ironically, to the reason that it’s tricky to see. It is overlaid by two other large craters: 24km Hainzel A to the north and 18km Hainzel C to the northeast.
The degree of overlap is severe. Co-joined themselves, Hainzel C and A obliterate most of Hainzel, overlying in excess of 50 per cent of its area. The structures that form this interesting trio are best seen under oblique illumination, in particular when the morning terminator is near, three days after first quarter. The old rugged, eroded surface of Hainzel is in stark contrast to the impressive terraced nature of Hainzel A to the north. Hainzel A is a much younger formation – obviously because it overlaps Hainzel – but its appearance is youthful too, with much of its internal rim terracing appearing sharp and well defined. This is a lovely feature to observe with a large telescope or using a highresolution imaging setup, as there is a huge amount of intricate detail to be captured. Like Hainzel A, Hainzel C has a central mountain peak, but its appearance is more like Hainzel: eroded, and illdefined. Hainzel C’s rim is irregular in shape and the whole crater looks as if someone has sanded it smooth. The transition between Hainzel A and C isn’t particulary well defined, the internal terraces of Hainzel A forming a rough border. The sharp southern edges of both craters do manage to delineate well from the rough formation of Hainzel to the south.
“Hainzel is easy to find but difficult to see as it’s overlaid by two large craters”
The trio is located in a rough highland region of the Moon and the surrounding area is littered with craters of all shapes and sizes. To the immediate south is the colossal walled plain of Mee, an ancient, eroded formation 133km in diameter. Although Mee isn’t that distinct, its general form is fairly easy to work out. When you bear in mind that it is twice the diameter of Hainzel, you realise just how much of the latter has been compromised due to being overlaid by Hainzel A and Hainzel C.
Heading east from Hainzel C brings you to another old but remarkably well-preserved crater in the form years old, the rim of Epimenides remains impressively sharp. It lies next to a similar-sized formation Epimenides S, which can appear quite complex under low illumination thanks to several smaller overlying craters. To the north of Epimenides and northeast of the Hainzel, A and C trio, lies the irregular, dark form of Lacus Timoris or Lake of of 27km Epimenides. Estimated to be over 3.9 billion Lacus Timoris Epimenides B Fear. This region is around 50km wide (north–south) at its widest point and 150km in length. Filled with lava, its dark, irregular shape stands out rather well against the brighter lunar highlands that surround it.