NASA's Hubble telescope a window on the universe

“I never felt there was any great risk in starting new ventures. The greater risk was missing an opportunity.†     

— Robert N. Noyce

NASA is interested in, and deals with, anything and everything that has to do with our solar system and especially with outer space. Remember, NASA stands for National Aeronautics and Space Administration. In order to gain knowledge and amplify understanding of the universe, NASA looks out into space with vehicles, orbiters, shuttles, telescopes and more.

One of NASA’s marvelous creations was the Hubble Space Telescope (HST), which was launched into orbit around the earth in 1990. It orbits at a distance of 350 miles from earth, and each orbit takes 97 minutes. At that distance, the telescope is well beyond the earth’s atmosphere, making it free from the distortions and interference that occur when telescopes take pictures while on the Earth itself.

The telescope was named for the great astronomer Edwin Hubble. Shortly after launching it,  NASA scientists discovered that a microscopic spherical aberration in the polishing of Hubble’s mirror significantly limited the telescope’s observing power.

It was studied extensively and in December 1993 a team of astronauts flew up to HST and performed a dramatic series of space walks to install an ingenious corrective optics package and other hardware. The defect was repaired wonderfully well and the elegant solution worked perfectly to restore Hubble’s capabilities. The photos taken with the Hubble telescope are among the greatest and most detailed ever done.

In the 1920s and 1930s, Edwin Hubble worked at the Wilson Observatory just north of Los Angeles, using the largest reflector telescope of that time, 100 inches in diameter. Hubble looked at objects in space that had never been identified before for what they really were. He discovered galaxies where these objects previously were seen as just fuzzy things in the sky, often called nebulas.

Using Doppler Radar effects, Hubble concluded that these galaxies were in motion, traveling farther and farther out in space, contradicting the then current belief that the universe was stable in dimension, or even decreasing in size.

Based upon his discoveries, Hubble and other astronomers began to think that if the galaxies were indeed expanding and moving farther out in space, then by going back in time they all had to have started their existence in one point. That new knowledge initiated the development of the big-bang theory.

The universe started its existence over 13-and-a-half billion years ago, as a pinpoint in size, which exploded. As the expansion continued, the ingredients started to take shapes and assemble themselves as nebulae, stars, comets and groups of stars forming galaxies.

Our Milky Way galaxy contains several billion stars and many objects, including asteroids, comets, planets and more. Other galaxies contain similar groups of stars.

The latest and best information about the continuous formation and destruction of galaxies has come from the astronomers who use the Hubble Space Telescope to view the universe and to collect information. Little by little, the Hubble telescope has photographed galaxies that were formed earlier and earlier and closer to the actual start of the big-bang. That has never been done before.

It was originally planned to stop the HST’s activities by 2005 to 2006. NASA’s chief administrator, Michael Griffin, decided that the Hubble telescope was too wonderful to be destroyed on this “early schedule,†and that it should be upgraded to remain active at least until the year 2012. Next year, in 2008, a group of space walkers will fly up to Hubble on a shuttle and add several important devices and whatever else would be useful to keep it going for five more years, or even more.

I look at the Hubble telescope as one of the most important and exotic devices ever created for the study of astronomy and the universe. It illustrates NASA’s real value and the benefits that NASA has delivered to mankind.

Hubble has several cameras that take pictures in regular light, in infrared and in ultraviolet. When you think of the telescope rotating around the Earth, making a full turn in 97 minutes, you might ask how the Hubble telescope can take pictures that are so clear and detailed and not fuzzy, due to its motion in space?

The HST is equipped with a device that can be focused on a specific star or galaxy or nebula, and keep the telescopic camera focused on it while it rotates around the earth. This device is controlled by space stations in the United States. And when you realize that the activities of the Hubble telescope are controlled and directed by scientists on Earth, you recognize the superb abilities of NASA people to do things that seemed absolutely impossible in the past.

You will enjoy looking at these three Web sites for some of the most exciting, beautiful and marvelous pictures and stories: hubblesite.org; seds.org/HST/hst.html; hubble.nasa.gov/index.php.

Sidney X Shore is a scientist, inventor and educator who lives in Sharon and holds more than 30 U.S. patents.