There are also
many new devices for detecting extrasolar planets.
In 2006, LBT , The Large Binocular Telescope,
started looking for Jupiters. The dual mirrors of LBT, peering into
space side by side, will phase starlight. This is called ‘Nulling
This process relies on the fact that light
waves have crests and troughs, just like waves of water. By precisely
aligning the light waves gathered by two mirrors from a particular
point in the sky, astronomers can overlap the wave crests from one
mirror with the troughs from the other so that the light simply
cancels itself out ( noise-cancelling headphones use the same principle
to deaden sound waves; with light, the result is a patch of darkness
This procedure can blot out the light of
a star so that a giant planet, hundreds of thousands of times fainter,
can be directly seen, as opposed to being detected by star wobbles
or dimmed starlight.
To be visible to an Earthbound telescope,
an alien Jupiter would have to be several times bigger or much younger.
( Still warm from its violent birth, a younger Jupiter would glow
in infrared light ). Devices like LBT, operating in orbit, are able
to see much more without the interference of the Earth’s atmosphere.
That sensitivity is important in finding
another planet of this Earth’s proportions, as, in relation
to the extrasolar planets so far found, it would exert only a feeble
tug on its star.