Mars will be in its opposition tomorrow night and it's probably the best time, when we put weather aside, for the observation of the Mars for all kinds of observers, especially for those with a small scope.
I couldn't afford to go to a really dark place, I could at my best, trying to go to a place with a sky patch containing the Mars, and allow me to watch for a considerable period of time. My site is mildly light polluted in my sense, or I should say, it's heavily light polluted in more people's sense, since I could read a book there without a flashlight. Anyway, it's not bad for me already.
I have setup everything at around 20:00p, but it's cloudy. Not all the sky was covered, but around 60-70% has been covered. Anyway, I guess I could wait, since the clouds were moving, though slowly. So, I prepared our dinner with my girl friend first. :)
After having the dinner, I occasionally got a short break from the clouds but it's just barely sufficient for me to point my scope to the Mars and then focused, then the view was blocked by the cloud again. It's rather frustrating, but I kept on waiting for better moments. Chats in-between.
I sat on the floor, waiting. And I've gone through the above point-but-no-observation cycles for three times or so. For the best one, I could center the Mars in my 20mm eyepiece and proceed to pick my Powermate up but when I was going back to the scope (I could do all the things without standing up), look up to the sky with naked eyes, the cloud moved back in again. Too bad!
At around 10:10p, a larger break of the cloud revealed. I could center the Mars in my 20mm and I could have a look on it at 120x when coupled with the parfocal Powermate, very convenient. At the first sight, I remembered the words that I've read from the past saying about the experience of observing the Mars, "It's probably the most frustrating object". Yes, a boring orange disc, showing virtually nothing. No polar ice-cap (later confirmed that it's not there at all, since it's summer at the facing side of the planet), no canals, it seemed that there's nothing there. Just a large color disc.
Yes, the sky was not so clear. So, I tried to lower the magnification to 75x, by using the 32mm with the Powermate. No major improvement except the image was brighter. Less waves of air were observed at this magnification than that at 120x, that means the seeing was bad as well. I knew that I've to be patient to wait at the moments with better sky conditions. I tried to use the #12 filter with the 20mm as well, the 120x view was not improved. I have also tried to pump up to 240x with the 20mm, Powermate and a 2x barlow, but the image could neither be improved nor be broken down.
Chromatic abberation was quite noticeable for the Mars at its opposition. When the focus was correct, the image was quite good; but a slight out of focus image was no good. Obvious red or purple shadings were seen around the planet disc at both sides of the inexact focus, making me think of seriously considering to upgrade to an apochromatic. :)
Actually, I could detect some hints of black markings on the disc, but those were not obvious and I didn't feel satisfied. It seems that I've to try again asap.
26-April-1999 insert: The polar ice-cap(s) is not visible at that night since it's not there at all. And as people reported, the surface features on the Mars are not as constrasty as those in the Jupiter or in the Saturn, so maybe it's really a frustrating object to be avoided. Anyway, why not have a try later?
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