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Ouch! A spiral galaxy as viewed edge-on collides with a small blue galaxy. From the Hubble Ultra Deep Field. Photo by NASA, ESA, S. Beckwith (STScI) and the HUDF Team.


astro101 -- your ticket to the universe!

Did you know???

Over a quarter million college students are enrolled in Introduction to Astronomy courses this year in colleges across the United States and Canada.

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"Kissing" Lakes found on Titan

NASA's Cassini-Huygens mission produced a radar image of two "kissing lakes" during a fly-by of Saturn's largest Moon, Titan. The lakes are filled with liquid, although it's not likely water. Instead, the lakes probably contain ethane and methane. The lake on the right appears to be drying out due to the approach of summer in Titan's Northern hemisphere.

Peeved about Pluto

The International Astronomical Union (IAU)International Astronomical Union (IAU) recently demoted Pluto from a ninth planet to a new category of object called a"dwarf planet." The organization sets three criteria for an object to be considered a planet:

(a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (c) has cleared the neighbourhood around its orbit.

For Pluto, the problem is with part C of the definition,since its orbit intersects Neptune's.

The demotion drew protests including from the widow and son of discoverer Clyde Tombaugh. In 1930, Tombaugh discovered Pluto at Lowell Observatory in Flagstaff Arizona.