Gone with the Wind

MAVEN (Mars Atmosphere and Volatile Evolution) spacecraft data shows that the primary reason the Martian atmosphere is gone is the activity of the solar wind early in the planet’s history (around four billion years ago). The solar wind is a stream of particles, mainly protons and electrons, flowing from the sun’s atmosphere at a speed of about one million miles per hour. Not only was the solar wind more intense then but the magnetic field generated by the core dynamo effect diminished as the core cooled and the dynamo stopped. With no magnetic field for protection from solar wind, the early atmosphere could be stripped away allowing bodies of water to vaporize away with the reduction of atmospheric pressure.

Happy Birthday ISS! Now 15 years old! – 220 visitors from17 countries. Over 5000 days of continuous human presence in space.

“Night Skies at The Observatory” this Thursday at the Franklin Institute, Michael Vogeley from Drexel will help us understand just where in the universe our solar system and our galaxy are positioned.

Pre-Dawn planets are still the best show ever!

Image: NASA/GSFC