Friday, I promised I would explain why the Hellas Basin (a huge crater) is special for being more than just big. Just read the facts to find out why.
1. The biggest crater on Mars is called The Hellas Basin, and this is what it looks like…
2. Scientists estimate that the asteroid that formed this crater struck about 3,900 million years ago, during the "intense early bombardment period." Here is just how big this crater is....
Hellas is 1,100 miles across.
(Extra Fact: The other impact basin shown here, Argyre, is the location of a farming colony in my book Vallar.)
3. Both American and Russian space vehicles have tried to detect a magnetic field on Mars, but it has no magnetic field. A compass on Mars would be useless. Since magnetic fields are created from moving molten iron at the core of a planet, this means that the core of Mars does not have an active churning iron core. One theory for no magnetic field, is that Mars is half the size of Earth and it's much colder, so it cooled off faster.
4. However, the Mars Global Surveyor discovered that the crust in the southern uplands was magnetized, which could only happen if Mars once had a magnetic field, and this confirmed it.
5. A handful of Martian rocks have been found on Earth that are magnetized, dating back to 4,500 million years ago.
6. It's believed that the impact crater that formed the Hellas Basin punched a hole in the crust and disrupted the magnetic field and Mars never remagnetized.
And now you know why the Hellas Basin is interesting for more than being just big.