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As we approach the Mars Opposition in November of 2005, amateur astronomers
and casual observers need to keep in mind a few things concerning observing this event through a telescope.
The primary thing driving what you need to see Mars is that Mars is always
going to be small, very small. Since Jupiter is in the sky right now (Sa 043005) view it and try and see detail on Jupiter.
Now imagine it around half its size, and that is Mars. Or when you view the Moon, remember that Mars is half the size
of any of the large craters on the Moon such as Copernicus.
The second thing that drives seeing details on Mars is that its small
size makes it more prone to the distortions caused by Earth's atmosphere.
So in general, a large telescope and steady seeing conditions will aid
in seeing Mars, but the view will remain small. The mount should be as steady as possible, since high magnifications
are needed to improve the view. Avoid hard dark surfaces, especially asphalt and concrete. These store a lot of
heat during the day and release it during the night, raisign havok with the view. Grass is the best, as it absorbs less
of the Sun's heat and releases it more slowly. Trees also help if they're not obstructing the view.
Below is my log of past oppositions, ordered from latest to earliest.
Enjoy !
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Su 010806 - As 2005 gave way to 2006, the weather and other commitments
kept me from imaging Mars until Sa 010706. By this time Mars was only 11 arc-seconds wide, gibbous, and retreating.
Add to this the general bad seeing conditions at the Griffith Observatory satellite facility, and my hopes weren't high.
In fact, I only took one 2-minute video run. After stacking and an initial filter application, Mars looked tiny in the
original image, seen below:
| Mars Sa 010706 Griffith Observatory |
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Although I don't favor electronically enlarging an image beyond
2x, this image was so small that I had to take a chance, so I selected a rectangular box around Mars measuring 160x120,
resampled and enlarged it to 640x480, and processed it as gently as I could. The result is the image below. The
round dark dot near the center of the disk is Sinus Meridiani. North is up, and celestial east is left. The Chryse
region is on the left limb. There is an amazing amount of detail considering that Mars is no larger than a quarter seen
from 520 yards or roughtly a third of a mile away. Now bad for a 127mm Maksutov operating at f/36 with a commercial
web camera !
| Mars Sa 010706 Griffith Observatory |
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Sunday, Nov 13th 2005 - Once again from the parking lot of the Griffith
Observatory satellite facility near Los Angeles on Saturday Nov 12th, using my 127mm aperture Maksutov operating at f/36,
with a 2x enlargement of the original image to help see details. Seeing was as good or better than the previous Saturday.
Part of this was the lack of Santa Ana winds for more than a couple of days, and part of it was due to the presence of humidity
in the air. Unfortunately, this also led to dewing . . . a lot of it. Consequently, a lot of surfaces, and
quite a few unprotected front optic elements got a good bath before the night was up at 930pm. I managed to avoid moisture
on the front optics of my Mak and on my laptop, the former thanks to a dew shield (why they don't automatically include one
with every SCT or Mak I could never understand) and the latter thanks to the heat it generated. My friend Jeff Schroeder
showed off his refractor's 11-inch objective lens, totally covered in droplets!
Image details are the same as for those from Nov 5th, except that visually the seeing
was better all throughout the night. Starting at around 7pm, the seeing was better at that time than at the same time
from Nov 5th, and kept getting better, although it never got 100% steady, a condition I personally haven't seem for almost
a decade.
| Mars - Nov 12th 2005 |
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| Click on image to see full size |
The above image shows one interesting feature; Nix Olympica is the light-colored
spot in the upper right quadrant of the image, and marks the spot of the largest volcano in the Solar System, Olympus Mons.
Evidence of either ice fields or ice clouds are see in the northern (top) part of the image. Solis Lacus, the Eye of
Mars, is seen just before it disappears beyond the rim of Mars in the lower right quadrant.
Below is a map naming the various features.
| To see a map of the above image |
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| Click on this image |
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Monday Nov 7th 2005 - On Saturday Nov 5th 2005, everything seemed
to come together. Reasonably steady skies with no clouds, some haze, and a good telescope. As a comparison of
the image below and the one further on shows, size doesn't always matter. My 127mm f/36 (f/12 with a 3x Barlow) showed
more detail than a C-14, albeit a lot of that was the much better seeing conditions in the parking lot of the Griffith Observatory
satellite facility over the rooftops of Caltech.
| Mars, Sa 110505 |
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| Click on image to see full size |
Almost every feature here has been verified to be something on the surface of Mars
by comparing it against more than a dozen other stacked images from the same night, taken at different times and with Mars
being in a different part of the frame. Below the image is annotated with the feature names.
| To see a map of the above image |
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| Click on this image |
Image details: November 5th 2005, 1045pm, Griffith Observatory satellite facility
near the Los Angeles Zoo. Individual images taken with an Orion (Syntha) 127mm f/12.1 Maksutov with a 3x Barlow and
Creative Pro eX camera shuttering at 1/10 sec. Over 600 images aligned and stacked to produce the original image, which
was filtered to bring out features using Registax and Paint Shop Pro.
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Thursday Nov 3rd 2005 - Well, after weeks of overcast and reported bad
seeing in the local mountains, it finally cleared. the local wind phenomenon known as the Santa Ana winds tend to clear
the air completely, but they also produce bad seeing, but when they're not around clouds tend to move in.
So it's a fight to see anything on any given night.
| Mars - Sa 102905 |
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| Click on image to see full size |
On Oct 29th a friend and I used the Caltech campus observatory with its
C-14 SCT to try and view Mars for the first time. It was clear but hazy, and the seeing was only fair, but the real
concern was the relatively poor optics in this telescope. The image above was the best of an hour's worth of data.
It was taken using a Creative Pro eX web camera, images selected and stacked with Registax 3.0, and final processing with
Pain Shop Peo. With an equivalent focal length of close to 300 inches (7,600 mm) The image size was how it appears below,
depending on your assumptions and calculations close to 900x.
I hope to get better images this weekend.
Enjoy !
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I hope to get improved images of Mars starting in early October.
Although recent web camera technology doesn't appear to offer more than 640 x 480 pixels for video, I hope to gain time
on large telescopes to increase the image size. I'll post more as the time approaches.
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| Mars, 30th Aug 2003 Opposition |
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| Click on image to see full size |
| To see a map of the above image |
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| Click on this image |
Mars as it was one brief instant during the 2003 opposition. I
reprocessed this image in 2005 since the original was very overprocessed in an attenpt to bring out details. After seeing
my Sa 110505 image above, a friend commented that it had a more natrual look than the old 2003 image, so I decided to redo
the older one. The image is in fact centered on Vallis Marinaris, the largest canyon in the Solar System. The
dark semi-circular feature on the left side is Solis Lacus, the Eye of Mars. The curved dark feature above it is Tithonius
Lacus, part of the western branch of Vallis Marinaris. Aurorae Sinus forms most of the dark complex at the center of the
image, and this is mostly the main bulk of the Vallis Marinaris complex. Chryse is the lighter colored region above
and between it and another dark region, Mare Acidalium
This image shows more detail than most observers will see through most
telescopes available to amateurs. It was taken through a 127 mm aperture f/12 Maksutov, boosted to f/24. The image
itself is enlarged from the original. It's the result of stacking hundreds of images from a web camera in order to minimize
the effects of Seeing. The image has been scaled up t replicate the image scale at f/36 with the same telescope.
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In 1995, I videoed Mars through a C-14 14 inch aperture telescope using
a Watek black-and-white surveillance camera, recording the composite video to Video-8 tape. But it was not until this
year (2005) that I was able to capture and process the data into my computer. The result is shown below.
| Mars, Feb 1995 Opposition |
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| Click on image to see full size |
Mars was just 14 arc-seconds during that opposition, 56% of the size
it would be in 2003. This time Solis Lacus is nearly centered in the image. The inability to manually set the
exposure time and gain, as well as the telescope not being in collimation, blurred the image, but it's both amazing and
sobering to see the details captured. Sobering, because from 2005 to 2018 this might be the best that we can see Mars
even at oppostion, but advancements in technology are always moving us forward.
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