Mars is a fascinating planet to observe as there are surface details to be seen upon its surface. There is also an opportunity to observe polar ice caps and cloud formations as the seasons on Mars progress.

Firstly, let's look at observing Mars with the naked eye and binoculars. A project worth carrying out is plotting the movement of Mars in relation to the background stars. Normally, Mars moves in a prograde direction, i.e. It moves from west to east. Then after a while, it will be noticed that the planet slows down and comes to a standstill for a day and then slowly starts to move in the opposite east to west direction. (retrograde direction). This continues for about 75 days and the planet will again be seen to slow down and stop in relation to the stars. Then again, the planet resumes its normal west to east direction. Why should this be?

Click here to view the “Retrograde Motion” applet below within a new window

Applet © Rob Scharein, Hypnagogic Software, Vancouver, BC, CANADA

Mars' diameter is small at a mere 4,219 miles, compared to the Earth's diameter of 7,926 miles. So this makes Mars relatively small object in a telescope. You can see surface details on Mars when it is close to the earth around opposition, even with a small 60mm refractor telescope. But to get a good view of Mars, a telescope of at least 150mm diameter will be required.

Mars comes to opposition about every two years. Opposition occurs when Mars is opposite to the Sun in our sky. This is also the time when Mars is closest to us. Usually, Mars is so far away that the disc of the planet is very small and no telescope will yield surface details. About 4 months prior to opposition, the planets disc will have grown to a reasonable size for observations to be made. It will be difficult as the disc will still be small but as the months pass, the planet gets ever bigger until around opposition day. After this day, the planet starts to move further away from us and the disc starts to shrink in size. Eventually, the disc becomes so small that we have to stop observing and await a year before the planet starts to approach the earth again.

Mars shows a distinct phase during the early and later part of the Mars observing window or apparition. This again is due to the position of the Earth and Mars in their different orbits. The smallest phase visible being about 85%. This must be taken into account when you make sketches of the planet.

Drawing Mars takes practice. When you first start observing planets, most people will not see much surface details. But after a number of days of observation, your eye becomes “trained” in detecting the subtle details on view. Only record what you can definitely see. If you're in doubt with seeing a specific detail, do not draw it on your sketch but do make a written note about it. Use a circle of 50mm diameter to represent the planet's disc. Start by noting the phase of the planet. Then you are in a position to start adding the subtle shading and white ice cap details. There may also be some clouds, dust storms and frost formations upon the Martian surface.

Drawing Mars as seen through a telescope

1. Start with a blank 50mm disk.

2. Draw in the phase if there is one. My sketch shows 85%.

3. Draw in any ice cap or polar cloud. My sketch shows an ice cap with a dark shading towards the ice cap edge.

4. Then draw in the subtle surface shadings that may be seen. My sketch shows the features Sinus Sabaeus, Mare Erythraeum in the south (upper half of disk) and Mare Acidalium in the north.

5. Finally finish off the sketch by smudging pencil marks to best represent the subtle shading. Note the bright area between Mare Erythraeun and Mare Acidalium. Remember that the drawing may have to greatly exaggerate the actual darkness of the subtle surface features seen.

Any drawing will need some basic data appended to it to have an observation that is of scientific value:

1. Date and Time. Record time as Universal Time (UT).

2. Telescope and Eyepiece used, e.g. 150mm F/8 Refractor at x120 (10mm Plössl).

3. If you have used a filter, you must say so. If not, state 'no filter used'.

4. Include the “seeing” conditions which relate to the stability of the image. A good scale to use is the Antoniadi Scale. This has a range of I to V, as follows: I - Exceptional steady image. II - Steady image with occasional slight wobbles in the image. III - Image is affected by large wobbles during steadier moments. IV - Image is constantly affected by atmospheric turbulence. V - Very poor image and making a sketch would not be possible.
   Also include an indication of how clear the sky is. A good scale would be 0 to 9 where 0 would equate to impossible to see through atmosphere and 9 would be a sky where the Milky Way is visible down to the horizon.

5. Some data on the planet Mars. This can be obtained from the British Astronomical Association Handbook that is published each year or planetarium software such as Guide 8. Record the planet's diameter in arc seconds, the phase, the central meridian at the time of the sketch, the solar longitude, the tilt of the planet.

6. Name of observer and name of observation site.

7. Along with the sketch, a written description will be of value.

Once you have made your sketch, you will want to identify the details that you have recorded. Consulting the map below will allow identification of most features.

CCD Imaging of Mars

Discussed here is the use of the Philips ToUcam 740K Model.

Technology has advanced to the extent that photographic techniques using film has become obsolete with recording details upon planets. The reason being due to film exposures being at the mercy of poor atmospheric stability during the single exposure applied to it. When using a web camera, the planet is exposed for fractions of a second for over 1000 exposures and with computer software, each individual is examined for quality and all the best snaps are combined to make a single clear and sharp picture.

Observations of Mars 2007-2008 Apparition