Mars, the red god of war, reached opposition on May 22nd!


Mars will then continue to move closer to Earth and will be the closest to Earth in some 11 years, on May 30th. At that time, Mars will be some 46,777,481 miles from Earth!

This is a close opposition for Mars and those with telescopes, will be able to see select

details on the planet. The planet Mars, will ride low in the S sky for observers in N. America and the northern hemisphere, making for some periods of unsteady air in which

to view the planet. The lower Mars is to the horizon, the less steady the air will be for viewing fine surface details. For those of you that have some experience with telescopes,

you will be treated to a view of Mars that is quite impressive. Mars will have a diameter of 18.6” of arc….larger than you may have seen it in years. Even still, Mars is a tough object to master!

The general rule of thumb of telescope magnification is this…. 50X per inch of telescope

diameter to maintain quality images. So, if you have a 6” telescope, you might not want to push the magnification beyond some 300x magnification.

Even at this magnification, the quality of the atmosphere is also a key component, to a positive observing session.

Mars is best seen by observers that have color filters to see and look deeper into the atmosphere of this unique world.


Yellow filters- W12-W15, help to bring out features in the desert regions


Orange filters- W21-W23A, help to bring out cloud formations above Mars


Red filters- W25-W29, help with with polar cap boundaries


Green filters- W57, help to bring out surface fogs on the planet


Blue filters- W80A,W38, help to bring out details in clouds and polar hoods

More information on the color of Mars and detecting features:



What color is Mars through a telescope? This question has been asked by astronomers for at least three centuries and is a subject of debate even today. Observers even report certain dark features on Mars grow darker and even change color during seasonal transitions. This has led to some startling conclusions, some of which has brought the wrath of the scientific community down on a few very prominent astronomers.

Confusion over the colors of Mars is nothing new. Reports of green or even blue features on Mars are common from ground-based observers. In the early 20th century, some astronomers saw the apparent greening of Martian maria, during spring and early summer, as proof that vegetation it was the cause. We have since found that the human eye is subject to a variety of illusionary perceptions, one being the inability for us to correctly identify colors in low light conditions. We may have a good idea of what the average human response to a particular color might be on Mars; however, observers often describe the planet’s colors completely different even while using the same telescope.

A layer of volcanic ash and rock covers the surface of Mars, at least in the smooth areas where the United States landed two spacecraft during the 1970’s. Using the robotics arms on each of the two Viking Landers the nearby surface was sampled and the results suggested a surface of ash-like material was saturated by water vapor. When similar materials on Earth are saturated to water vapor it tends to darken and/or change color hues. Also, during the colder Martian seasons its surface has been observed covered with frost or snow like condensates that tend to brighten some areas and make adjacent dark areas appear darker that they really are.

Hoar frost in Earth’s surface tends to clump ash-like and sandy materials into mounds or irregular piles, which will appear darker, especially when accompanied with long shadows. However, when viewed from certain incident angles, these same piles may appear brighter.

Using the proper color filters one can determine colors of Martian features, usually red; however, we have found that certain atmospheric clouds display blue-to-blue white color at times [Beish et al, 1988]. Even without filters there are a few clouds that appear bluish, such as the “Capen Blue Syrtis Cloud.” This cloud shows up often during Martian northern spring (southern autumn) and will appear blue-white visually. In photographs taken with color film and tri-color CCD images this cloud is a vivid blue. To prove this the observer can use a yellow filter on Mars to see this particular blue cloud turn greenish in the filtered image. It is usually brighter in blue color, that is while observing Mars with a blue filter, and darker in red light.

Dust clouds often appear bright yellow in the telescope without observing with filters. They are usually brightest in red light, but can be also bright in yellow light. Dust clouds will be blurry or hazy in yellow light. A blue filter will not brighten the dust cloud and often will make the dust cloud appear to vanish. However, we have found that white-yellowish clouds can accompany dust clouds so the observer should watch for these phenomena. Look for a dusty polar cap following any dust clouds they show up in red and green light.

Since Mars is red in color it will be brightest in red or orange filters. While observing Mars using a deep blue or violet filter the surface features will most often disappear and only a dull bluish haze will been seen. Occasionally surface features will appear dark in deep blue light, a phenomenon not well understood.

Here are some tips when viewing Mars in the telescope:

2016 Apr 17

Ls 138.6°  De  5.9°  Ds 16.4°  RA 16:29  Dec -21.3°  A.Dia 14.1’’

Retrogression Begins. Mars begins retrogression, or retrograde motion against the background stars 10 months after conjunction, when it appears

to move backwards toward the west for a brief period before, during and after opposition.  Clouds and frosts prominent in north. Clouds area in south.

Syrtis Major broad. (NPC Width ~13° ±1°).

2016 May 22

Ls 156.3°  De  10.4°  Ds   9.9°  RA 15:58  Dec -21.7°  A.Dia 18.4’’

Mars at Opposition. Are both polar hoods visible? SPH present and edge of NPH visible.  Hellas frost covered?  Are W-clouds present?

Is Morpheos Lacus (228°W, 37°N) prominent? Are topographic clouds prominent in Libya, Aeria, Moab, Edom, and Candor?

2016 May 30

Ls 161.0°  De 11.9°  Ds  8.2°  RA 15:46  Dec -21.5°  A.Dia 18.6’’

Mars at Closest Approach. Is Mare Acidalium broad and dark? Bright spots in Tempe-Arcadia-Tharsis-Amazoins? “Domino effect”

appears around 120° – 125° Ls. Topographic clouds increase.

2016 Jun 29

Ls 176.8°  De 15.4°  Ds  1.3° RA 15:19  Dec -21.0°  A.Dia 16.6’’

Retrogression Ends. Mars begins westward motion against the background stars. South Polar Cap (SPC) maximum width.   Is the North Polar Hood present?

Does SPH or frost cover Hellas? Hellas should begin to clear and darken. Are W-clouds present? South cap emerges from darkness of Winter.

SPH thinning and forms “Life Saver Effect”?

2016 Jul 05

Ls 180°  De  15.4°  Ds  -0.1°  RA 15:20  Dec -21.2°  A.Dia 15.9’’

Equinox – Northern Autumn/Southern Spring. South Polar Cap (SPC) maximum width.   Is the North Polar Hood present?

Does SPH or frost cover Hellas? Hellas should begin to clear and darken. Are W-clouds present? South cap emerges from darkness of Winter.

SPH thinning and forms “Life Saver Effect”?

2016 Aug 12

Ls 202.3°  De 11.1°  Ds -9.3°  RA 16:04  Dec -23.7°  A.Dia 12’

SPC shrinking. Syrtis Major darkens and continues to shrink. W-clouds possible. Surface details increasing in contrast

Hellas the features Zea Locus and Alpheus dark? SPC Novissima Thyle (300°-330°W) projection present?  (SPC width ~52° ±6°).

2016 Sep 08

Ls 218.7°  De  4.7°  Ds -15.4°  RA 17:06  Dec -25.5°  A.Dia 10’’

Bright SPC projection Novissima Thyle  (300°W – 330°W) Areographic longitude. Dark rift Rima Augusta connected from 60° to 270° longitude.

Rima Australis visible in SPC (290°-350°W)? W-clouds possible. SPC bright projection Argenteus Mons (10°W-20°W).

SPC Dust clouds in Serpentis-Hellespontus, in Hellas or Noachis?   (SPC width ~44° ±3°).

2016 Oct 18

Ls 243.8°  De  -7.3°  Ds -22.5°  RA 19:01  Dec -24.8°  A.Dia 8’’

SPC rapid retreat. Novus Mons small, bright, and high-contrast. Rima Australis widens. SPC isolated bright spot at 155° longitude?

Any white patches near -20° latitude may brighten.

Atmosphere of Mars very clear during Ls 240°- 250°.

Occasional morning limb hazes. Dust clouds? Note: Several “planet-encircling dust storms have been reported during this season

at 24° Ls. (SPC width ~28° ±3°).

2016 Oct 29

Ls 251°  De -10.8°  Ds  -23.7°  RA 19:37  Dec -23.6°  A.Dia 7.6’’

Mars at Perihelion. SPC in rapid retreat. Novus Mons smaller. Dust clouds expected over Serpentis-Hellaspontus (Ls 250° – 270°).

Syrtis Major beginning to narrow. Frost in bright deserts? Orographic clouds (W-clouds) possible. Elysium and Arsia Mons bright?

Note: Several “planet-encircling dust storms have been reported during this season.  High probability 255° Ls. (SPC width ~ 24° ±3°).

2016 Nov 29

Ls 270°  De -19.2°  Ds  -25.2°  RA 21:10  Dec -17.8°  A.Dia 6.6’’

Solstice – Northern Winter/Southern Summer. W-clouds present? NPH extends 50° N? Decreased number of White clouds.

“Syrtis Blue Cloud”? White areas in deserts? Dust clouds in south until 270° Ls?  Watch for planetary system clouds bands.

Orographic cloud over Arsia Mons? Syrtis Major is narrow.  (SPC width ~ 17° ±2°).









Mars Observation Links:




What side of Mars is visible now!