This is an image of Olympus Mons.
Click on image for full size
The largest volcano in the solar system is Olympus Mons, shown in the image to the left. Olympus Mons is a Martian shield volcano. The altitude of Olympus Mons is three times the altitude of the largest peak on Earth, Mt. Everest, and is as wide as the entire chain of Hawaiian Islands. Measurements returned by Mars Global surveyor demonstrate the unbelievable size of Olympus Mons. Olympus Mons is a very large volcano for a body as small as Mars. Mars is three times smaller than the Earth! The size of Olympus Mons suggests something special about the surface of Mars and how Mars cooled over time.
Mars has several other *very* large volcanoes. Some of them are located on top of a big bulge in the side of Mars called the Tharsis Ridge. The volcanoes were formed in a manner similar to that in which the Hawaiian Islands came into being on Earth, namely from a hot balloon of material which rises from the deep interior of the planet and forms land on the surface. The size of these volcanoes suggests that, Mars had already cooled off and formed a crust thick enough to hold up the large volcanoes without allowing them to sink as they formed.
Shop Windows to the Universe Science Store!
Our online store
includes issues of NESTA's quarterly journal, The Earth Scientist
, full of classroom activities on different topics in Earth and space science, ranging from seismology
, rocks and minerals
, and Earth system science
You might also be interested in:
How did life evolve on Earth? The answer to this question can help us understand our past and prepare for our future. Although evolution provides credible and reliable answers, polls show that many people turn away from science, seeking other explanations with which they are more comfortable....more
Shield volcanoes can grow to be very big. In fact, the oldest continental regions of Earth may be the remains of ancient shield volcanoes. Unlike the composite volcanoes which are tall and thin, shield...more
Mars is small. Mars is about 1/3 the size of the Earth. This means that it cooled off very fast. Mars probably started colder than the other earth-like planets. Then, Mars cooled rapidly from the outside,...more
This image, taken from the Mars Global Surveyor mission (MGS), shows the Tharsis Ridge, the green/blue area in the middle of the picture, as well as a portion of the southern hemisphere of Mars. The green...more
Volcanism is part of the process of bringing material from the deep interior of a planet and spilling it forth on the surface. Eruptions also eject new molecules into the atmosphere. Volcanism is part...more
This is an example of the cratered surface of Mars. Almost the entire surface of Mars is covered with craters. Craters can be wiped out over time, so a surface which has many craters is very old. The lowlands...more
Unlike Earth, there is no continental drift on Mars today. The Martian surface does not seem to have changed or moved in billions of years. The evidence for this fact can be found in two ways. 1.) The...more
The surface of Mars consists of highlands and lowlands. The highlands are in the southern hemisphere (the bottom of the figure), and the lowlands are in the northern hemisphere of Mars (top of the figure)....more