Seeing What's Out There

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Ever since Galileo discovered the moons of Jupiter using a four centimeter telescope, astronomers have tried to build bigger and better telescopes to see what's out there.

When lens size became a limitation, they added mirrors, which got bigger and bigger as telescopes improved.  Then new electronic detectors were added that allowed them to collect more of the light reaching the telescope.  Then they compensated for atmospheric movement.

Now there are plans afoot to build a huge telescope, with a mirror a hundred meters across, as large as a football field.  This enormous telescope, which would take up to twenty years to build, would have a light collecting area a hundred times greater than existing instruments.  It would have forty times the observing power of the Hubble space telescope.

Astronomers are sticking with ground based telescopes because the cost of sending something this massive into space would be prohibitively expensive.  Building a larger telescope on the far side of the moon, using small launches of to- be- assembled parts is another approach that, though technically feasible, would also be too costly.

Astronomers believe that with this large telescope many of the mysteries about the Universe will be answered –– including the nature of black holes, and the mysterious dark matter that pervades the Universe, as well as the dark energy that is pushing it apart.

So next time you look at a night sky, remember there is a lot more out there yet to be seen.