schneiderism

Posts lately have been all things solar system, and that is because there is so much going on right now with regards to robotic exploration of Jupiter, Saturn, Mars and the their various moons. It is an exciting time to be a space exploration geek. I just came across the above image taken by the ESA’s Venus Express explorer of a vortex occurring in the southern polar region of the planet. This image was captured by Express back in 2006. I also found an excellent image montage of Express approaching Venus that shows some detail in the cloud covering that surrounds Venus.

Venus Express is essentially a reconfiguration of the ESA’s Mars Express explorer technology and left for Venus back in 2005. The goals for Venus Express are to explore the atmospheric composition and circulation on Earth’s closest neighbor, as well as how the atmosphere interacts with the planet’s surface. Venus is definitely inhospitable, with an atmosphere mostly comprised of noxious gasses and an incredibly hot surface temperature. Surprisingly, given the close proximity of Venus, we still know very, very little about the planet. Venus Express is helping to change this.

I came across this composite image last evening and it stopped me in my tracks. Click on it to view larger, it’s worth it. Here is an enormous, active chain of volcanic calderas, named Tvashtar Catena, on Jupiter’s moon Io and we get to see it in amazing detail and color. This is a color intensified composite made up of images taken by Galileo back in 2000 and composited by Ricardo Nunes.

Back in 1999 the Galileo Orbiter snapped some pictures of an active fissure eruption in this caldera. The eruption let loose lava flows that were 30km long and 1.5km high. Here’s a composited image from those pictures:

Io is the most volcanic body in our solar system with its surface literally covered in lava lakes, giant calderas, and active lava flows. The color of Io is mostly due to the huge amounts of sulfur that blanket its surface from all of this activity, which has remained continuous as long as we have been able to observe this moon. We have measured volcanic eruptions on this moon that have created sulfurous plumes 500km high. Because Io orbits closely to Jupiter it is subject to intense electromagnetic radiation. As Jupiter’s magnetosphere rotates it sweeps Io and strips away nearly 1 ton per second of volcanic gases and other materials. Io actually acts as an enormous electrical generator as it moves through Jupiter’s magnetic field developing 400,000 volts across its diameter and generating 3 million amperes that flow across the magnetic field and into Jupiter’s ionosphere.