KMSP - On Monday our solar system’s smallest planet Mercury appears to cross the disk of the sun as seen from Earth. While this doesn’t sound like it has the star power (pun intended) of a supernova or a black hole, it is a fairly rare event and could provide NASA some detailed information about the planet’s thin atmosphere, assist in the hunt for worlds around other stars, and help hone some of NASA’s instruments.
This event occurs about 13 times a century. Split evenly, that would be once about every 8 years. But in reality, they come in waves. The last one to occur was back in 2006 and before that, in 2003. Both for both of these, Earth was nearly as far away from Mercury as we get in our orbit, making it tough for our older technology to have high enough resolution to learn anything substantial. But this one is different.
Mercury transits the sun either in May or November, but a May transit provides A LOT more information because Mercury is much closer to Earth than in the fall. However, these May transits are far more rare than its fall counterpart occurring less than a third of the time. The next May transit won’t occur again until 2049, so for scientists across the globe who are likely in the heart of their career, it’s now or never.
NASA scientists are viewing the transit through many specialized telescopes from their Solar and Heliospheric Observatory (SOHO) and the Solar Dynamics Observatory (SDO), along with the Japan Aerospace Exploration Agency-led Hinode solar mission.
Here are some pictures from the transit and a timeline of events...