A Good Time To Look At Mars!

(Plain Text Version)

When I step outside around midnight, I am awed by a bright red object high in the Southeastern sky.  This is Mars, on its way to a close approach to Earth.

The orbits of the two planets are such that we have a close approach every 26 months.  Because our orbits are elongated, some approaches are closer than others.  This year’s approach will be closer than normal.  In addition, Mars is much higher in the sky (in the Northern Hemisphere) than usual.  This allows better views through a telescope.

A little terminology: Earth—Mars Opposition.  In a “top view” of the solar  system, if you can draw a straight line first through the Sun, next through Earth and then through Mars, we say that Earth and Mars are at opposition (this definition is oversimplified).  The closest approach of the two planets occurs within a few days of opposition. 

The brightness of Mars is impressive, even without a telescope.  Mars will increase in brightness until October 6, 2020.  After this date, Mars will begin to fade.

With a telescope, some surface details can be seen, although they are not as sharp as those of Jupiter and Saturn.  At first glance, a bright orange glow dominates the view.  The polar ice cap is currently small, but contrasts well with the orange background.  With patience, darker areas should appear.  For brief instants, the turbulent layers in our atmosphere cancel each other and   allow clear views.  By watching carefully through the eyepiece, one can take advantage of these opportunities.  (Most of the good photos of Mars are made from high-speed videos.  Image-processing software selects the sharpest frames and combines them into a single image.)

To get a good look, the telescope should be of a higher grade than “beginner”.  Many owners of high-quality scopes love to make them available at star parties.  Unfortunately, social distancing is difficult for large groups at night.  For a small group, keeping distance may be possible, but the eyepiece can be a route for infection.  We can pick up the virus when our eyelashes touch the eyepiece.  Disinfecting the eyepiece after each user could prevent this, but the eyepiece could be damaged.  A good look at Mars is not worth risking your health!