How To Get The Best Views of Mars

How To Get The Best Views of Mars

You've probably seen a very bright yellow-orange star rising from the East as the sun sets. That's Mars! October 13th is the Mars opposition—the best and brightest Mars will be for two more years. Don't worry if you can't get out to see Mars on the 13th though—it will still be extremely bright and brilliant for the next several weeks, through mid-November, when it will begin gradually dimming as the planet moves further away again in its orbit. 

How Big Will Mars Be?

This tends to get exaggerated every opposition. As we perceive them, Mars and the other planets are all tiny compared to our Moon. How tiny? The image below shows Mars, Jupiter, and Saturn to scale with our Moon at their opposition sizes (their largest) for this year.

If Mars Is So Tiny, How Can I Get A Good View?

This is where a good telescopes comes in! Telescopes do two things: (1) collect more light to allow you to see dim objects, and (2) allow you to magnify small objects. What you need to see Mars in any detail is a telescope with an aperture of 5" or larger (ideally 8" or larger) and as much magnification as the telescope and the local atmospheric conditions will allow.

Telescope Magnification

Telescope magnification has two practical limits. The first limit is based on the aperture (diameter) of the telescope's primary mirror or lens. Typically this is simplified to 50x per inch or aperture, or 2x per millimeter. So, a 4" telescope can, in theory, support up to 200x magnification. Remember, this is the upper limit, not the ideal!

The second limitation is the atmosphere itself. Have you ever noticed the stars twinkling at night? The stars themselves don't actually twinkle. What you are seeing is the effect of the air currents and moisture in the atmosphere causing diffraction of the light from those stars. We see the same thing, only magnified, through a telescope. (Astronomers refer to the level of this atmospheric turbulence as Seeing.)

So, on a night where there is a lot of twinkle in those stars, more magnification just magnifies that twinkle and turbulence, producing a very wavy, washed out image. On those nights where the air is still, and there is no twinkle at all in those stars, the seeing is considered excellent, and you can use higher magnification in your telescope. There is still a practical upper limit though—about 300x is the highest useful magnification even with excellent seeing.

Does that mean you never need more than a 6" telescope? After all, 6" x 50x per inch gives you that 300x maximum magnification, right? Well, not so fast. The real point of a telescope is less about magnification, and more about light gathering. The more light you can gather, the brighter and clearer the image, and the greater the actual resolution of the image. So, while you can in very good seeing conditions push a 6" telescope to 300x, doing the same with a 10" telescope will still give you a vastly clearer and brighter image. Aperture really is king, particularly for planets!

What Telescope Do I Need?

I suggest a telescope of 8" or larger, but even a small telescope will give you a view of Mars worth seeing. You don't need a computerized telescope—just a basic manual telescope will let you see Mars. If you want to get a good telescope with large aperture on the cheap, take a look at our selection of Dobsonians. You can currently find an 8" Dobsonian telescope for just under $450.

Eyepieces & Barlows

Having a good high magnification eyepiece or two will definitely help you enjoy Mars at its best, but be sure you aren't going to go over the maximum magnification of your telescope, or use too much magnification on a poor night. Remember, in perfect conditions, a 6" or larger telescope can handle 300x magnification. On most nights, 150x will be the useful maximum. That number drops with smaller telescopes. 

To figure out the magnification of an eyepiece with your telescope, take the focal length of your telescope, and divide it by the size of the eyepiece (this will be marked on the side of the eyepiece in mm). For example, a 2000mm focal length telescope with a 10mm eyepiece will have a magnification of 200x.

Planetary Filters

Mars is actually so bright, that it's a little too bright in a big telescope! This is where planetary filters help - colored filters add contrast to the view, making it easier to pick out details on the planets. We offer several filters, including the brand new Celestron Mars filter, and filter kits, to help you get the best views.

Photographing Mars

What to take a quick snapshot? Pick up the Celestron NexYZ Smatphone adapter to make aligning your smartphone with your telescope a little easier. 

What to do something higher quality? Planetary cameras are the best option. Connect these to your telescope in-place of the eyepiece, and plug in your laptop to record a video and post-process a high quality planet image. (I highly recommend an 8" or larger telescope for this).

Have a DSLR Camera? You can connect it directly to your telescope with a T-ring, and a t-adapter barlow to use instead of a planetary camera for either single shots, or a video to later stack into a better single image.

Do I Need Dark Skies?

No! Your backyard in the city will do just fine for enjoying the planets! Unlike deep sky objects that are very dim and easily washed out by light pollution, the bright planets can be enjoyed from anywhere. No need for a big trip - just pull out the telescope, and enjoy the views!

What's Next?

  1. Add a high magnification eyepiece or barlow.
  2. Add a planetary filter or filter kit.
  3. Need help selecting a Telescope, Eyepieces, or other gear? Give us a call: 1-877-279-5280 or Message us on Facebook.