Thursday, June 12, 2008

The Telescope Opens Up the Universe

Welcome back to What's Up?

Summer solstice, the first official day of Summer, is approaching on June 21. That means the nights will be getting shorter, and warmer weather will be moving in to make the Summer constellations more enjoyable.

June is my favorite month of the year for one main reason: it's the month when I got my first telescope a few years ago. It was a refractor, the same type as the one invented 400 years ago.

The telescope appears to have been invented way back in 1608 by Hans Lippershey. He was also the first person to create binoculars. Immediately, the military forces found use for it in battle. Word spread quickly across Europe (just like gossip here on the Island!) via word of mouth and mail. Within one year an Italian man, named Galileo Galilei, heard of this miraculous invention.

The name for "telescope" comes from "tele" - meaning far - and "skopein", meaning "to look or see". It was given to Galileo's first scope and has stuck ever since.

Galileo was curious about this odd device, so he built his own and pointed it towards the heavens above. What he saw bewildered him. The moon is covered in thousands of craters. The planets are visible as discs and aren't just points of light. Venus goes through phases like the moon. Jupiter has its own moons. Saturn has a ring-like structure around it. That's just to name a few of his discoveries!

He actually proved that the moon and planets are other worlds, like Earth.

Since then, telescope technology has advanced dramatically with telescopes getting larger and larger. The objective mirrors, the main mirrors in reflecting telescopes, are now up to about ten meters (30 feet) in diameter! This craving for aperture increase is commonly referred to as "aperture fever".

Telescopes that have mirrors ten meters in diameter require extremely well grinded mirrors. These mirrors are so smooth that if they were blown up to the size of the earth, the largest bump or "hill" on them would be no higher than a doorstop!

A plan for a telescope about one hundred meters across (328 feet) - about the size of an NFL football - has been proposed to the European Space Agency (ESA). The telescope has been named the Over-Whelmingly Large Telescope - OWL for short. It is so huge that the mirrors have mechanical "fingers" that hold the mirror in shape.

With these new telescopes incredible detail can be seen, but size comes with a downside. The atmosphere is turbulent and distorts images just like the fluctuating hot air over a hot paved road. But now, the advanced technology called "adaptive optics" allows astronomers to see through our turbulent atmosphere and use these telescopes to their full potential.

The idea around adaptive optics is fairly simple. The telescope shoots a few lasers into the atmosphere, and computers then monitor how the light beams move around. Then the computers change the shape of the mirror to reverse these effects. This hasn't been possible until now, thanks to the huge amount of processing power in today's computers.

With this computer power astronomers are "linking" telescopes together. This allows much better resolution, which means more detail is visible.

With adaptive optics being incorporated into telescopes, space-based tools like the Hubble telescope won't be needed as much since we are now able to see clearly through the atmosphere. Space based telescopes will still be useful, however, to see types of light that can't be seen through the atmosphere because the atmosphere absorbs them. A few examples of light that can't be seen through our atmosphere are gamma-rays, X-rays, UV-rays, infra-red, and some radio waves.

By sending telescopes that can see these bizarre types of light, we can see things our eyes normally can't see. These include galaxies that are normally hidden behind the Milky Way's dust clouds, baby stars inside nebula, and bursts of gamma-rays and X-rays from black holes.

Now let's peer skyward and see what's up.

The new moon was on the 3rd this month, and so the full moon will be on the 18th.

Summer Solstice, the first day of Summer, is on June 20th.

June 10th is the fifth anniversary of the launch of the Spirit rover. Originally designed to last only a few months, this rover has lasted years and is still operational! Its twin, the Opportunity rover, was launched within a few months of Spirit and is also still operational.

Speaking of Mars, you probably have heard that late last month the Phoenix lander landed on Mars. It carries a disk containing the names of the present and past members of the Athena Community Astronomy Club. This lander will be digging for ice, organic compounds, and signs of past or present life. You can keep track of its progress on the web at "".

This lander also contains a weather monitoring station and you can also keep updated on recent Martian weather reports here too. At a typical high temperature of -30 degrees Celsius, Mars doesn't seem that far away from home!

Until next month, just look up!

Hey Kids...
You, too, can send your names to another world - the Moon. A mission to the moon, called LRO, which is being run by NASA, will be bringing along a disc containing the names of many people like you and me. All you have to do is go to their web site "" and type in your first name and last name in the spaces provided. Then click the "Add Name" button and your name will be added to the disc and your name will be sent to the moon!

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