Observing Planets Under A Little Hazy Sky?

Aren’t the astronomers hate the hazy sky? Apparently, it is not. It is more depended on the objects that they observe. If you are going to observe DSO(deep sky objects) as well as other faint objects, or astrophotography(except plantes photography), you must have a stable and clear sky to get amazingly good result!

Why is the sky with a little haze is the best to observe planets?

Shall I quote the words from my telescope dealer?

Malaysia has hazy skies most times because of the great amount of water vapour and condensate in our highly humid climate. These reduce the sky transparency which is very important for observing most deepsky objects that are relatively faint. Planets are bright objects and “tranparency” is less of an issue. However there are lots of surface details that can be seen in planets but only if the sky is steady, or in other words, if the “seeing” is going. A clear and transparent sky is not always accompanied by good “seeing”…infact the opposite tends to be the case. When the sky is very transparent, the air temperature tends to drop rapidly (because of uninhibited thermal raditation from the land surface) and this causes air movements and turbulence which cases bad “seeing”. You can detect bad seeing by presence of wildly twickling stars. Stars in Malaysian skies infact “twinkle” less because we do not have rapidly falling temperatures at night and to some degree this seems to be so because of the moderating influence of the high humidity. So a slighly hazy sky, rather than a very clear sky tends to be steadier, has better “seeing” which is good for observing fine details on planets and the moon because they do not “swim” around as much in turbulence.

The high humidity of our air however causes the main frustration we experience here: after sunset wen the temeperature drops a little, that small drop in temperature is enough to condense water droplets out of the water vapour…and we see clouds forming almost immediately after sunset. Clouds block verything from view. If humidity is not so high, the slight haze that forms does not block the planets from view, but they do block faint deepsky objects.

The reason Northern Chile is such a superb place for astronomy is the coastal mountains have dry air that gives excellent transparency and the proximity of the strong and constantly cold Humbolt Current keeps temperatures fairly steady, providing very good seeing as well! Unlike other deserts (llike in Australia & Africa), the Atacama does not experience extreme temperature swings between day & night…it is just extremely dry at all times (again because of the Humbolt Current).

He takes Malaysia(my country) as the example to explain this phenomenon as Malaysia is near to equator. Thus, the weather here is always hazy and cloudy. He has also explained the reason I like to observe the planets. So now, do you know why a little hazy sky is even better than a clear sky when it comes to planets observation?