There’s always wonder
when it comes to other planets and other worlds in the universe.
Do they exist? Is our solar system unique or is it an example of
other stellar setups?
Take a look at our own solar system. The center is a star – the
Sun – and surrounding it are major and dwarf planets, as well as
dust, gas, asteroids, comets, and moons. Each planet has its own
As the third planet from the Sun, it takes Earth 365 days to
make one complete trip around. What keeps Earth in orbit? The
Sun’s gravity of course; and therein lies the clue to other
solar systems: Gravity of a central star.
The difficulty in identifying other planets has always been the
fact that they generate no light of their own. They only reflect
light and if so, faintly. Thus, finding them in deep space is
challenging to say the least.
Fortunately, a workaround was devised.
The key was to look for similar stellar setups in space and
subsequently, similar motion (a tug and pull). If astronomers
could identify a star and then determine orbital movement
amongst objects around that star, then a planet could be
Indeed, theory and proof collided in 1992 when Alex Wolszczan
and Dale Frail made the landmark discovery of three planets
orbiting a pulsar. Though not a star, their breakthrough changed
everything for the astronomical community. It confirmed that
they were all on the right track.
Then came 1995, when Michel Mayor and Didier Queloz made their
own announcement: The discovery of 51 Pegasi b, an extrasolar
planet orbiting a star very much like our Sun (51 Pegasi). The
confirmation of other solar systems was complete.
Did You Know:
hundreds of other alien planets have been identified using the
same observational method.
In October of
2009 alone, an incredible 32 new planets were added to the
count, bringing the total to over 400!.