 Because the orbit of the Moon is tilted only 5 ° from the ecliptic , the interior of this crater lies in perpetual darkness . Estimates of the area in permanent shadow were obtained from Earth @-@ based radar studies . Peaks along the rim of the crater are almost continually illuminated by sunlight , spending about 80 – 90 % of each lunar orbit exposed to the Sun . Continuously illuminated mountains have been termed peaks of eternal light and have been predicted to exist since the 1900s . 
 Because the orbit of the Moon is tilted only 5 ° from the ecliptic , the interior of this crater <a href='uninflect' title='1'><mark>lies</mark></a> in perpetual darkness . Estimates of the area in permanent shadow <a href='uninflect' title='2'><mark>were</mark></a> obtained from Earth @-@ based radar studies . Peaks along the rim of the crater are almost continually illuminated by sunlight , spending about 80 – 90 % of each lunar orbit exposed to the Sun . Continuously illuminated mountains <a href='been_done' title='3'><mark>have</mark></a> been termed peaks of eternal light and <a href='been_done' title='4'><mark>have</mark></a> been predicted to exist since the 1900s . 
Cuz the orbit of the Moon is tilted only 5 ° from the ecliptic , da interior of dis crater lie in perpetual darkness . Estimates of tdaarea in permanent shadow was obtained from Earth @-@ based radar studies . Peaks along thdaim of the crater r almost continually illuminated by sunlight , spending abt 80 – 90 % of each lunar orbit exposed to thedan . Continuously illuminated mountains done been termed peaks of eternal light and done been predicted to exist since the 1900s .