Saturday, January 27, 2007

121)Medieval castles, the Moon and lessons from bright planet Venus.

A brilliant night-time scene of our Moon and the planet Venus, the 2nd rocky planet from the Sun(planets Mercury, Earth and Mars are, respectively, the 1st, 3rd and 4th rocky planets from the Sun. This picture is interesting also for its backdrop, which is the Castle Almodovar in Almodovar, near Cordoba, built during the muslim Ummayad era in Spain during the 8th century:

http://antwrp.gsfc.nasa.gov/apod/ap070127.html


Rocky planet Venus is the brightest planet in our night sky in the Northern Hemisphere. However, while this is certainly beneficial for our viewing pleasure, the only reason Venus is so bright is because it is surrounded by very thick clouds made of carbon dioxide, which reflect sunlight very well. What we see when we look up at Venus, then, is not the planet's surface but the thick clouds of carbon dioxide that completely shroud the planet's surface from view. Contrast that to the brilliantly azure mixed with wispy white clouds picture of our planet earth as taken by the Apollo astronauts from the Moon in the late 1960s(Earthrise, the picture that made people fall in love with Astronomy):

http://antwrp.gsfc.nasa.gov/apod/ap051224.html

The temperature on earth-sized Venus is about 485 degrees C day and night and this is directly the consequence of the greenhouse effect, where UV rays from sunlight stream onto the planet, change to infrared waves after hitting the surface, causing tremendous heat generation, and are prevented from escaping by the thick carbon dioxide cloud cover that makes up the planet's atmosphere. The resulting global warming is what causes Venus's around the clock surface temperature to be so high:

http://antwrp.gsfc.nasa.gov/apod/ap950815.html

Now, where else have I heard the phrase Global Warming before?

easynash

Islam, eminently logical, placing the greatest emphasis on knowledge, purports to understand God's creation:Aga Khan 4.
The God of the Quran is the One whose Ayats(Signs) are the Universe in which we live, move and have our being:Aga Khan 3