Philips Atlas of the Universe

Maps of the Satellites of Uranus

ATLAS OF THE UNIVERSE

W

hen Voyager 2 flew by Uranus in January 1986, it

allowed detailed maps of the planet’s satellites to be

made for the first time.

MirandaThe landscape is incredibly varied, and something

of a jumble. The main features are the three coronae:

Elsinore, Arden (‘the Race-Track’) and Inverness (‘the

Chevron’). There are few large craters. Voyager 2 passed

Miranda at only 3000 kilometres (1880 miles), and the

pictures sent back gave a resolution down to 600 metres

(2000 feet), so that the views of Miranda are more detailed

than those of any other world except those upon which

spacecraft have actually landed.

ArielAriel was imaged from 130,000 kilometres (81,000

miles), giving a resolution down to 2.4 kilometres (1.5

miles). There are many craters, some with bright rims and

ray-systems, but the main features are the broad, branch-

ing, smooth-floored valleys such as Korrigan Chasma and

Kewpie Chasma. There are also grooves, sinuous scarps,

and faults. Ariel’s surface seems to be younger than those

of the other major satellites.

Umbriel The most detailed picture of the Umbriel’s

darkish, rather subdued surface was taken from a range

of 537,000 kilometres (335,000 miles), giving a resolution of

about 10 kilometres (6 miles). The most prominent crater

is Skynd, on the terminator; it is 110 kilometres (68 miles)

in diameter, with a bright central or near-central peak. The

other bright feature, Wunda, is much more puzzling. It

seems to be a ring about 140 kilometres (87 miles) across,

but is so badly placed that its form cannot be made out,

though it is probably a crater.

Titania Like Ariel, Titania seems to have experienced

considerable tectonic activity in the past. On the best

Voyager view, obtained from a range of 369,000 kilometres

(230,000 miles), many craters are shown, together with

linear troughs and fault valleys. The 200-kilometre (125-mile)

crater Ursula is cut by a fault valley over 100 kilometres

(62 miles) wide; the largest formation, Gertrude, may be

more in the nature of a basin than a true crater. There are

ice-cliffs and valleys such as Messina Chasma, which is

1500 kilometres (940 miles) long.

Oberon Oberon was imaged from 660,000 kilometres

(412,000 miles), giving a resolution down to 12 kilometres

(7.5 miles). There are many craters, some of which, such as

Hamlet, Othello and Falstaff, have dark floors. One interest-

ing feature is a lofty mountain, about 6 kilometres (3.75

miles) high, shown on the best Voyager picture exactly at

the edge of the disk, near Macbeth, so that it protrudes

from the limb (otherwise it might not be identifiable).

Whether or not it is exceptional, we do not know. Only new

observations will tell.

MIRANDA ARIEL

Lat. °S Long. °E

Arden Corona 10–60 30–120

Dunsinane Regio 20–75 345–65

Elsinore Corona 10–42 215–305

Ferdinand 36 208

Gonzalo 13 75

Inverness Corona 38–90 0–350

Mantua Regio 10–90 75–300

Prospero 35 323

Sicilia Regio 10–50 295–340

Trinculo 67 168

Lat. °S Long. °E

Ataksak 53 225

Brownie Chasma 5–21 325–357

Domovoy 72 339

Kachina Chasma 24–40 210–280

Kewpie Chasma 15–42 307–335

Korrigan Chasma 25–46 328–353

Kra Chasma 32–36 355–002

Laica 22 44

Mab 39 353

Sylph Chasma 45–50 328–015

Yangoor 68 260

180°

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240° 120°

300° 60°

210° 150°

330° 30°

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