A NASA Hubble Space Telescope image of a spiral-shaped disk of hot gas in the core of active galaxy M87. Hubble measurements show the disk is rotating so rapidly it contains a massive black hole at its hub. Source: NASA
The razor-sharp images from the repaired Hubble Space Telescope bring the incredible splendor of distant heavenly objects into human view for the first time. Recently, for example, scientists used the Hubble to gather evidence that a massive black hole really exists at the center of a neighboring galaxy. Confronting--and even solving--some of the deepest mysteries of the universe may have no seemingly practical payoff, but it nonetheless appeals to the deep-seated human desire for knowledge of how we fit into the cosmos. Story Musgrave, the payload commander for the recent Hubble servicing mission, put it this way: "I have thought of that instrument as contributing to my personal ideas about what my place in the universe is, what it is to be human."
The Hubble telescope revealed a pancake-shaped disk of hot gas at the center of the giant M87 galaxy. So sharp was the image that astronomers could see by the pattern of movement that the spinning disk of gas was being sucked down into and swallowed by something at the center. Measurements with the telescope determined the speed of the gas--an incredible 1.2 million miles per hour-- allowing astronomers to calculate the mass of the central object. It is equal to 2 to 3 billion suns, so massive for its size that it could only be a black hole--a collapsed condition of matter whose gravitational pull is so strong that not even light can escape. Black holes are predicted by Einstein's theory of general relativity and have been suspected on the basis of other astronomical evidence, but they are such a strange and novel phenomenon that some scientists have remained skeptical. Now the new Hubble observations have provided proof--"the smoking gun", as one astronomer put it.
In addition to such dramatic discoveries, the Hubble is also being used to study the size and age of the universe, the evolution of galaxies from minute fluctuations in the early cosmos, and the details of star birth and star death. There are still plenty of mysteries to unravel about the vastness of space surrounding our planetary home--mysteries that are now in better focus.
The refurbished Hubble Space Telescope is a triumph of technology and human ingenuity, captured in the public mind by the sight of NASA's astronauts unfurling Hubble's new solar panels in space, against the distant backdrop of our home planet. The Hubble servicing mission demonstrated what can happen when scientists and engineers join together to solve a difficult problem. The flawed mirror was discovered soon after Hubble's 1990 launch. A team immediately gathered to examine dozens of possible "fixes". The resulting corrective device, an optical jukebox called COSTAR, was devised and built in only 26 months. Combined with the remarkable ability of the astronauts who installed it and otherwise upgraded the space telescope, the result placed innovative technology in the service of humanity's vision and age-old quest for knowledge about our environment and our place in it.