In recent days, some of those criticizing NASA's proposed budget have tried to paint a picture of an agency without a vision. In fact, nothing could be further from the truth.
NASA's far-reaching ambitions in space science have been, and will continue to be, truly inspiring.
Just a few decades ago, cynical scientists used to say that there are only two facts known with certainty about the cosmos at large: that the sky is dark at night, and that our universe is expanding. This situation has changed drastically, and it has changed largely thanks to NASA's bold efforts in space science.
It is because of NASA's impressive science initiatives that we now know the properties of galaxies at such distances that their light started on its way to us when the universe was only 4 percent of its current age. Until 1992 we did not know of a single planet outside our solar system, but we have been able to determine even the composition of the atmospheres of a few of the 430 planets around other suns discovered since. Black holes were transformed from mythical entities in Disney movies into objects that are known to reside at the center of most galaxies. We understand our Sun and its effects on Earth much better. And this is just the tip of the iceberg.
NASA's achievements in space science have contributed even to a large number of technologies in areas ranging from the development of micro-endoscopes -- tools that enable surgeons to view what is happening inside the body on a screen -- to, believe it or not, the sharpening of record-breaking ice skates.
Astronomer Edwin Hubble, after whom the Hubble Space Telescope is named, wrote: "With increasing distance our knowledge fades and fades rapidly.
Eventually we reach the dim boundary, the utmost limit of our telescope. There we measure shadows, and we search among ghostly errors of measurement for landmarks that are scarcely more substantial. The search will continue. Not until the empirical resources are exhausted need we pass to the dreamy realm of speculation."
NASA's search for origins will continue too -- the origin of the universe, of our Milky Way Galaxy, and of life within it.
NASA's proposed Earth Science program, coupled with a host of no fewer than 11 planetary probes, will provide invaluable data not only on the Earth's atmosphere and the Earth's resources (both crucial for managing climate change), but also on asteroids that could endanger Earth, and on Mars and Europa -- potential sites for primitive life in the solar system.
The Solar Dynamics Observatory, which was just launched Feb. 11, will help us understand the Sun's influence on Earth and near-Earth space by studying the solar atmosphere in unprecedented detail.
The Kepler spacecraft that was launched last year will determine for the first time the frequency of Earth-like planets orbiting other stars -- a huge step forward in the search for extraterrestrial life.
The James Webb Space Telescope, to be launched in 2014, will reveal the very first galaxies to have formed in the universe. And the list goes on and on. Humans have always been driven by a desire to understand the cosmos. Their endeavors to get to the bottom of "how did all of this start?" far exceeded those needed for mere survival.
NASA's scientific explorations are a source of inspiration for the next generation of scientists, mathematicians and engineers. There is no grander vision than this.
Mario Livio is an astrophysicist and head of the Office of Public Outreach at the Space Telescope Science Institute in Baltimore. His e-mail is firstname.lastname@example.org.