Folks,
Some of you may be tired of reading (and forwarding) emails and text messages about the "Two Moons" or the "Two Suns", so here's something real.
Jupiter, the largest planet in the Sun's family, is closer to Earth than anytime since 1963 until 2022. The closest approach ("opposition") is on 20th September 2010. Now, you won't see two Moons in the sky that night, but throughout this month, Jupiter will be more than twelve times bigger than Mars. Through a telescope at about 37X, Jupiter appears as big as the Moon does to the unaided eye. Mind it. You won't receive a chain email about this because this is true and not a hoax.
Facts for the Curious:
Jupiter rotates fast, completing one orbit in less than ten hours. Because of this, the planet has a distinctive oval shape which can be clearly seen with the smallest telescopes.
The planet has 63 moons. Four of these are big enough to be seen with the slightest optical aid, and are at different positions every night. One of these moons, Io, is the most geologically active object in the Solar System; it has more than 400 active volcanoes. Yikes.
A large anticyclonic storm has been raging on Jupiter since God knows when. Known as the Great Red Spot (GRS), it was first observed by humans more than 200 years ago. Storms on Earth, you know, hardly last a week or two at peak intensity. Now, guess the size of the GRS? Three times the diameter of the Earth! Wind speeds? Exceeding 500km/h. This storm can be observed with telescopes of 4" or larger aperture.
There are smaller storms as well. In the storm called LRS, wind speeds peak at an impressive 620 km/h, far exceeding the 250 km/h threshold that would make it a devastating Category 5 hurricane on Earth.
So much for now. Have a good day.
________________
"Yes, I'm an astronomer since 1995. Sorry, I won't read the palm of your hand".
Karachi Astronomers Society