Although most of the fanfare surrounding NASA's 50th anniversary centered on July 29, which marked half a century since America's space agency was created by an act of Congress, it was actually 50 years ago today--October 1, 1958--that NASA opened its doors to its employees. So break out the Tang, and set off a few bottle rockets! Through triumphs, tragedies, and disappointments, our space program has persevered, opening our eyes to incredible worlds and wonders, and its mission continues.

NASA has compiled an impressive list of achievements. It's launched numerous successful manned missions, culminating with the six Moon landings. Manned space stations going back to Skylab have tested the ability of humans to live and work for prolonged periods in space. Earth-observing satellites have greatly deepened our understanding of Earth's oceans, climate, geology, vegetation, resources, and more.

Orbiting observatories, exemplified by the Hubble Space Telescope but also including satellites to study celestial objects at every conceivable wavelength, have made numerous discoveries. Our fleet of robotic space probes has visited all of the planets in our solar system, revealing them and their moons and enigmatic worlds, as well as comets, moons, and asteroids fascinating and enigmatic worlds. (Five of these probes are heading clear out of the solar system on one-way journeys to the stars.)

NASA's efforts have revolutionized our understanding of the universe and our place in it. Particularly in its early decades, the space program helped engender an excitement that led many students to pursue careers in sciences. And NASA technology has been applied to numerous areas unrelated to space.

Along with such obvious things as missile design and communications systems, NASA technology has found applications in areas as diverse as wireless headsets, plasma displays, freeze-dried foods, single-crystal silicon solar cells, portable electric vacuum cleaners, cochlear implants, bicycle helmets, air purifiers, airplane collision-avoidance and anti-icing systems, oil-spill remediation, flame-retardant coatings, better two-way radios, anthrax detectors, skis, tennis racquets, and dialysis machines.

Of course, NASA has had its share of tragedies as well--the launch-pad fire that killed the Apollo 1 astronauts, the Challenger and Columbia disasters--and failed missions, such as the Mars Climate Orbiter, which crashed into the Red Planet because subcontractor Lockheed Martin had used English units of measurement instead of NASA-mandated metric units, and of course Apollo 13, where only the heroic efforts of both mission and ground crews saved the astronauts from death.

What do the next 50 years offer? It's been 35 years since astronauts walked on the Moon, but it looks like we're going back. NASA's Constellation program is developing a new set of spacecraft for manned missions as a successor to the Space Shuttle. It probably won't be until at least 2020 until we return to the Moon (I'd like to see them aim for July 20, 2019, the 50th anniversary of the first Moon landing), and perhaps 2030 before we get to Mars, the limiting factor largely being money.

However, if life were discovered on Mars by a rover or other unmanned craft, that would speed things up--as would teaming with an international partner or partners. China, which just completed its third manned space flight and has its eyes set on the Moon, is a likely rival. Many other nations, including Japan, Brazil, and India, have initiated unmanned space programs.

Budgetary considerations, particularly in light of the current economic situation, could play a major role in determining our future in space. Both John McCain and Barack Obama have vowed to continue funding the Constellation program if elected president.

As a senator, McCain has been supportive of the space program over the years, though he's promised that as president he would watch the budget like a hawk, and NASA programs could prove expendable. At one point, Obama suggested taking money from NASA to fund an early education program, but now says that any such an offset would have to come from elsewhere. His stated reason for the change is a growing realization of how the Bush Administration's anti-science tack had cut into dollars for basic research. In August, he came out in favor of $2 billion in additional funding for NASA. He also wants to resurrect the National Space Council to help provide focus and direction to the space program. As to what either of them would actually do in office, only time will tell--and a lot may depend on the effects of our current economic crisis.

Manned landings on the inner planets (Mercury and Venus) are improbable due to these worlds' searing surface temperatures, though astronauts might fly by Venus on the way home from Mars. Manned exploration of the outer solar system will probably have to wait for NASA's centennial.

As for unmanned missions, several flights are currently underway. The New Horizons mission, due to fly by Pluto in 2015, was conceived and launched when that ice-world was still classified as a planet. The Dawn mission is headed towards two of the largest asteroids, Vesta and Ceres. (Like Pluto, they're now officially classified as "dwarf planets".) The Messenger mission, launched in 2004, is en route to Mercury, using "gravity assists" from close flybys of several worlds (Earth, Venus, and Mercury itself) as it matches speeds with the innermost planet, which lies deep in the Sun's "gravitational well." Messenger won't actually enter orbit around Mercury until 2011.

Mars has been an object of intense interest to NASA since the space program's early years. Ongoing missions such as the Spirit and Opportunity Mars rovers are still going strong, and the Phoenix Mars polar lander, which in its short stay has already detected water as well as soil possibly conducive to life. Additional rovers and missions to return samples of Martian soil to Earth are in the works.

Last winter, NASA tested a prototype submersible in the icy waters of Lake Mendota in Wisconsin, and there's talk of testing this sub in Lake Vostok, an enormous lake that lies more than 2 miles beneath the Antarctic ice cap. Its eventual mission could be to explore the subsurface ocean beneath the icy crust of Jupiter's moon Europa.

One of the great quests that NASA is involved in, and will be in the coming decades, is in the finding of planets orbiting other suns. James Webb Space Telescope, a 6.5-meter telescope, is scheduled to replace Hubble in 2013. It's most sensitive in the infrared part of the spectrum, and has the potential to take images of large planets orbiting other stars. (Currently, such planets are only detectable by indirect means, either by noticing minute, periodic changes in a star's brightness as a much smaller planet passes across the star's face, or through shifts in a star's spectrum as the planet wobbles back and forth due to the pull of an unseen planet.)

In part thanks to NASA, our understanding of the physical universe is a quantum leap ahead of where it was a half-century ago. The cosmic background radiation left over from the Big Bang. Planets mapped and studied from up close. Planetoids lurking at the fringe of our solar system, and whole planetary systems orbiting other stars. Moons with vast oceans under their crusts. Moons with ethane/methane seas. Dark energy, and a universe expanding at an ever-increasing rate. The sky, imaged at every conceivable wavelength. Sure, we can make projections about various programs and missions to come, but with the pace of both technology and discovery, we must leave room for possibilities as unimaginable to us as the world and cosmos as we understand them today would have been to the people of 50 years ago.

Post by Tony Hoffman