Historical Society Gets An Update On The Hubble Telescope

By Jan Howard

The meeting room of the C.H. Booth Library was filled to capacity November 8 with residents interested in the development and discoveries of the Hubble space telescope. Some of those in attendance had worked on the design and development of the space telescope in Danbury.

Linda Abramowicz-Reed, a Goodrich engineer who worked on the Hubble for about 20 years, presented a lecture and slide show, sponsored by the Newtown Historical Society. The Goodrich Corporation in Danbury, formerly Perkin-Elmer, played a key role in the design and development of the telescope and its guidance system.

In 1946 Dr Lyman Spitzer envisioned a telescope in space. In the 1970s, Perkin-Elmer was awarded the contract to design it.

The telescope has been in space for 14 years. It is 43.5 feet in length, 14 feet in diameter, and weighs 25,500 pounds. NASA designed the telescope so that astronauts could easily remove the observatory’s science instruments and components during on-orbit servicing calls and replace them with more technologically advanced equipment. This approach was adopted to protect the telescope against instrument and equipment failures over its 20-year mission.

It is currently equipped with spectrographs and cameras sensitive to ultraviolet, visible, and infrared light.

Ms Abramowicz-Reed discussed the reasons for studying space and the advantages of a space-based telescope.

“A space-based telescope can overcome the effects of the earth’s atmosphere,” she said. “Clouds can obstruct the view and air currents and cells distort light from the target.”

She explained that Hubble has the advantage of being unaffected by weather, is capable of observation at any time, can see the entire sky, and can see ultraviolet light. Ground-based telescopes are limited by weather and observation can be only at night, she noted.

“Hubble sees visible light and different wavelengths,” she said.

“Hubble is the first of NASA’s observatories. It is 380 miles above earth and has traveled over 1.7 billion miles,” she said.

“It resolves images 24,000 times better than the human eye. It can guide on a target or see a target the width of a human hair three miles away,” Ms Abramowicz-Reed said.

Once the telescope observes a celestial object, its computers convert the image or data into numbers that are beamed down to Earth via communications satellites. The data is then reconverted into information and pictures, which scientists study.

Following the launch of the Hubble, it was discovered that its mirror was flawed, causing blurry vision. The error was traced, and a correction made.

“Its instruments were designed to be replaced by astronauts,” Ms Abramowicz-Reed said. “Astronauts talk about how beautiful the Hubbell mission is.” There have been four shuttle missions to it.

“It’s a wonderful thing that it has been brought up to date every few years,” she said.

Last year, she noted, NASA decided there would be no additional servicing missions to Hubble because of the aging shuttles. “They’re looking into a robotic mission,” she said.

The telescope has three fine guidance sensors, each the size of a baby grand piano, weighing 500 pounds, that send pitch and yaw information to the spacecraft. They also give the signal to keep it stable and straight.

The telescope has made it possible to study the solar system and galaxy evolution, understand how stars and planets form, measure the size and age of the universe, and test theories not verifiable in a laboratory.

Slides featuring Hubble’s discoveries, such as star formations and violent explosions of dying stars, such as supernovas, highlighted her lecture.

“I like explosive events,” she said. She explained that in 2002 a giant red star puffed up and then collapsed back down. “It didn’t explode.”

Among the telescope’s discoveries are black holes, moving them from scientific theory to scientific fact. “These are intriguing,” she said. “Most of the time light can’t escape from them.”

Ms Abramowicz-Reed also discussed two other observatories currently operating in space. The optics system for the Chandra, which sees x-rays, was also built in Danbury. It is 200 times higher than Hubbell, more than one-third the way to the moon.

The Spitzer space telescope sees infrared wavelengths. The primary mirror was made in Danbury.

The reason for the different types of telescopes is that scientists need to see objects in different perspectives. The three programs are starting to merge, Ms Abramowicz-Reed said. “We can see visible as well as x-ray and infrared.”

She said scientists are currently working on an infrared telescope that would be launched in 2012.

According to a pamphlet about the Hubbell, with more than 100,000 images to its credit since it was launched in 1990, the Hubble has become perhaps the best-known observatory ever built, and may one day answer one of the oldest questions known to man: How big and how old is our universe?