Mercury and Venus Conjunction

Hey, did anyone float yesterday? Some silly prankster convinced a few people that they would. 

Since our feet are planted firmly on the ground and our minds are full of scientific reasoning, let's turn our attention to an actual cool event regarding the planets Mercury and Venus this week. If you look towards the southwest after sunset, you should be able to spot Venus low on the horizon. It looks like an exceptionally bright star. If you look a little below and to the right of Venus, you might be able to spot Mercury, which is always hard to see because it is only visible at twilight and is low on the horizon. See image below showing Venus and Mercury tonight. 

Mercury and Venus close together at twilight. Image Credit: Stellarium

You might need to use binoculars to see Mercury tonight. Use Venus as your guide, and Mercury should be in the same field of view. Because Mercury is so close to the Sun, it is only visible just after sunset or before sunrise. The Sun's glow in the sky makes Mercury hard to spot. If Mercury were visible in the darkness of the night, it would appear nearly as bright as Jupiter in our sky.

Mercury and Venus appear close together tonight, and will be getting closer and closer as the week progresses. On Saturday evening, January 10, the two planets will be only 0.6 degrees apart in our sky - a conjunction. See image below. 

45 minutes after sunset. This Saturday will be your best chance to see Mercury for a few months. Image credit: Stellarium

So are the two planets actually close together? Sort of. Mercury is the first planet from the Sun, and orbits once every 88 days. Venus, the second planet, takes 225 days to orbit. Mercury has recently lapped Venus, but they are still relatively close together. Mars also happens to be on that side of the Sun right now, making all three planets visible after sunset. See image below. 

Mercury, Venus, and Mars are grouped together on the same side of the Sun as the Earth right now. Image credit: solarsystemscope.com

Mercury has been orbited by the MESSENGER spacecraft since March of 2011. It has completed several 360 degree high resolution maps of the surface, which you can explore here. Check out some of these striking images: 

This false color image of Mercury shows differences in the surface rocks of Mercury. Image Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Image Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Rembrandt crater at sunset. Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

This week would be a great time to spot Mercury in our evening sky! If you would like to learn more about the planets or astronomy, you might be interested in the adult astronomy class we are offering at the Peoria Riverfront Museum. Or check out our newest show, Tour the Solar System - Live! 

If you just want a place to relax during your busy day, we can provide that as well. Join us for Relax Under the Stars, a free event, this Wednesday, January 7, from Noon-1:00. Thanks for reading, and keep looking up!