Accessibility links

Hubble Space Telescope Provides Spectacular New Photos - 2002-05-01


The Hubble Space Telescope recently upgraded by U.S. space shuttle astronauts has returned what the U.S. space agency NASA calls the most spectacular views of the universe. The new photos show a menagerie of stellar and galactic shapes near the fringes of the cosmos.

Jubilant astronomers have unveiled Hubble's latest pictures, captured by the new Advanced Camera for Surveys that is 10 times more sensitive than what it replaced.

"When we saw the first images, my colleagues and I were stunned. We had underestimated how extraordinary the new images would be."

Johns Hopkins University astronomer Holland Ford is the principal investigator for the camera. He said, "The Advanced Camera gives Hubble and humanity a new window on the universe. This new window is the widest and clearest that Hubble has ever had."

The Advanced Camera replaced the Deep Field Camera, which took an important 40-hour-long exposure of 3,000 faint, distant galaxies in 1995. Mr. Ford said the new camera has surveyed a patch of sky twice as large as the old one, still just the size of two grains of sand held at arm's length, and picked out twice as many galaxies. "This is remarkable," he said, "because the exposure time was one-twelfth the time needed for the first Hubble Deep Field."

Like the Deep Field image, the galaxies in the new picture are in various stages of evolution stretching back 13 billion years to when the universe was only about one billion years old. But the Advanced Camera images are more detailed so sharp, in fact, that astronomers can identify building blocks of galaxies and colliding galaxies near the edge of the cosmos.

In one picture, a collision between two spiral galaxies called The Mice foretells what may be the fate of our galaxy. Mr. Ford said, "Our Milky Way and our nearest large neighbor, the Andromeda galaxy, are falling toward one another. Several billion years in the future, Milky Way and Andromeda will eventually merge, forming a large elliptical galaxy."

The new Hubble pictures also include a galaxy 420 million light years away that looks like a stellar tadpole because of its long, streaky tail.

The images are the first to be released since U.S. space shuttle astronauts installed the advanced camera and other new equipment on Hubble during five spacewalks in March.

A member of that crew, astronomer John Grunsfeld, said the orbiting telescope is in incredible shape. "It's been in orbit for 12 years and we turned Hubble into a brand new telescope," he said. So I think what we're seeing today is really quite literally just the tip of the iceberg.

Johns Hopkins astronomer Holland Ford says as good as the new pictures are, Hubble's advance camera is really intended to look farther away and thus, longer ago to the time when the universe first lit up. Mr. Ford said, "One of the things that we may do with this camera, that I hope we will do and we certainly will try very hard, is to look at those galaxies that are forming in this twilight zone between a universe that is illuminated by stars, galaxies, and quasars and the universe that was dark before there were stars and galaxies."

When Hubble first orbited in 1990, astronomers expected that it's original equipment would find the first light. That was when they thought stars and galaxies formed about two billion years after the birth of the cosmos.

But NASA space science chief Ed Weiler said that when researchers peered that far back with the telescope and saw no darkness, they realized that star and galaxy formation came much earlier than they had believed. Mr. Weiler said, "It has shown us that some of our most closely held beliefs about cosmology were just plain wrong."

Now astronomers know the first stars shone within one billion years of the cosmos' birth, which is thought to have occurred in a cataclysmic explosion called the Big Bang.

But University of California astronomer Garth Illingworth says no one knows precisely when. "This is why it's called the dark ages," he said. "We don't know. It could go back to a few hundred million years from the Big Bang [or] 500 million years. This camera gives us an opportunity to explore into that region, but this is one of the toughest problems we face."

NASA wants to keep the Hubble operating to answer these questions until 2010. It is developing a successor with even more acute vision called the Next Generation Space Telescope.

XS
SM
MD
LG