Sky & Telescope - USA (2020-06)

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as north and south of the crater. There

are suggestions that the Ohm rays

extend 150 km farther into Oceanus

Procellarum. Finally, other rays to

observe from a farside crater radiate

from Giordano Bruno and extend at

least 975 km to the crater Alhazen,

east of Mare Crisium.

All of the rays and mountains

described here are observable from

your backyard with a small telescope,

though the peaks will require a very

favorable libration. You won’t see very

far onto the lunar farside, but you can

observe features that mark major land-

forms otherwise completely specula-

tive without spacecraft data.

¢Contributing Editor CHUCK WOOD

often observes the libration zones.

qqqThe tall peaks of the

former Doerfel and Leibnitz

Mountains are labeled with

Schröter’s original designa-

tions. South is up.

qqThis QuickMap image

shows rays from the crater

Ohm on the lunar farside, ex-

tending to Russell in western

Oceanus Procellarum.

qEjecta rays from the

crater Giordano Bruno on

the lunar farside extend

to Alhazen crater east of

Mare Crisium.

NASA / GSFC / ARIZONA STATE UNIVERSITY (3)

Russell

Ohm

Mare Crisium

Hausen

Drygalski

Doerfel Mountains

Alhazen

Giordano Bruno

Demonax

Leibnitz

Mountains

B

A C

D

E

Cabeus

Ashbrook

α

γ β

δ