Moon closes in on Mercury: Saturn low

Event Date: October 16th
Time: 6:45 PM


Brief

   Let's show something fun.  What, you ask??  The Moon creeping up on Mercury (-0.1), which is getting closer to greatest elongation.  The planet has been very gradually separating from the Sun, and now enough so that we can see it for a brief time once the Sun gets low enough.
   Before getting to the "creep", the first image shows the Moon and Mercury just under 1º separated.  As seen from locations such as Hawaii, viewers can see the Moon moved a little more east towards Mercury, and the pair closer together. Also, being a latitude closer to the equator, it is a little easier to see Mercury above the horizon.  Mercury's orbit shows as well.

Detailed

   As I showed two days ago, the Moon was a very old, waning crescent.  Although it is just past new now and not easily visible until it is dark enough, we will see it better tomorrow.  The geometry of the southwest, evening sky is only slowly improving this month, meaning that the Moon is low to the horizon; the Sun's glare gets in the way as well.  
   The second image is a fun one, for if you have a telescope and/or the right optics to give a wide field: center on the Moon, and watch as Mercury slips into the field.  Granted, time is short, as the Moon sets only 51 minutes after the Sun.  Note that the orbits of the two--although not displayed--means no occulation, although we see that every so often if the nodes for their orbits meet at that right place.

click on images to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp.