Geology of Mars of the dichotomy places a significant constraint on theories of its origin. Straddling the dichotomy boundary in Mars's western hemisphere is a massive volcano-tectonic province known as the Tharsis region or the Tharsis bulge. This immense, elevated structure is thousands of kilometers in diameter and covers up to 25% of the planet’s surface. Averaging 7–10 km above datum (Martian "sea" level), Tharsis contains the highest elevations on the planet and the largest known volcanoes in the Solar System. Three enormous volcanoes, Ascraeus Mons, Pavonis Mons, and Arsia Mons (collectively known as the Tharsis Montes), sit aligned NE-SW along the crest
The Magic School Bus Lost in the Solar System after all the clues have been exhausted. Clicking on the "Friz-finder" will determine whether Ms. Frizzle is anywhere on the current planet. If she is, then the game is completed, but if she is not then the user will have to collect another token to activate the "Friz-finder" to try again. The Magic School Bus Lost in the Solar System The Magic School Bus Lost in the Solar System is the fourth book in Joanna Cole and Bruce Degen's "The Magic School Bus" series. The book depicts arguably the most well-known adventure of the series and introduces the character of