Sinuous rilles, such as
Hadley Rille, mark locations where rapidly flowing lavas cut winding channels.
Apollo 15 commander David Scott had been driving around the moon's
Hadley Rille on his third and last outing when he pulled out a pouch from under his seat.
Clearly, in any event, there exist at least two very different types of lunar 'trench', the rather rectilinear clefts of the Sirsalis or Ariadaeus form and the sinuous features typified by the
Hadley Rille. As these sometimes coexist in close proximity in the same landscape --as in the Hadley/ Archimedes/ Mt Bradley area--it seems illogical to assert the same mechanism for the origin of both.
The most famous sinuous rille,
Hadley Rille (upper right), lies much farther east near the Apennine Mountains.
As a title in the Archaelogy Series from
Hadley Rille Books, Mayflies was created to be an "archaeologically-accurate novel ...
They collected 169 lbs (76.8kg) of moon rock from 12 different sites including
Hadley Rille, an ancient channel believed to have been carved by torrents of flowing lava.
And Apollo 15 landed near a vast chasm in the lunar surface,
Hadley Rille.
On Earth, recent examples can be seen on the flanks of Kilauea volcano in Hawaii, while on the Moon,
Hadley Rille, visited by Apollo 15 in 1971, is believed to have formed in the same way billions of years ago.
He recently finished a far-future novel, Empire Ship, and his first novel, Transcendence, will appear in 2010 from
Hadley Rille Books.
Generally, these long, narrow depressions are either straight (like the Ariadaeus Rille), concentric (such as the beautiful Hippalus Rilles on the east side of Mare Humorum), or sinuous (typified by the famous
Hadley Rille where Apollo 15 astronauts David Scott and James Irwin landed).
Swooping in over the Apennine Mountains, Dave Scott and Jim Irwin plunked their lunar module, Falcon, down onto a narrow plain between soaring mountains and an ancient lava channel known as
Hadley Rille. Compared to the earlier missions, Apollo 15 carried more scientific instruments and a lunar rover--a small, lightweight electric car that allowed the astronauts to roam five times farther afield than previous crews.
"The most famous is
Hadley Rille, where the Apollo 15 spacecraft moon lander came down near," he added.