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Ad Astra
Volume 15, Number 4 September/October/November 2003

Mission Control
Spacebeat

What's Up

Prometheus Unbound
A Promethean plan to explore the outer planets using nuclear-powered spacecraft is a step closer to reality following NASA’s go-ahead to investigate miniature nuclear reactors. Project Prometheus, named after the Greek god who gave humanity fire, will concentrate on nuclear energy, which is the only form of power that can meet the mission’s requirements. The aim is to build an interplanetary space probe capable of flying vast distances and beaming scientific information back to Earth.

“Project Prometheus will develop the means to efficiently increase power for spacecraft, thereby fundamentally increasing our capability for Solar System exploration,” said a NASA spokesperson. “Increased power for spacecraft means not only traveling farther or faster, but...[also] exploring more efficiently with enormously greater scientific return.”

NASA’s plans to use nuclear-powered probes to peruse the planets have prompted passionate opposition from anti-nuclear activists. However, development of space nuclear power plants will free missions that would otherwise be chained to rocky inner worlds due to lack of power. Feeble solar-powered probes are useless in the outer solar system, where the sunlight is weak, and current spacecraft powered by radiothermal generators (RTGs) operate on the power equivalent to a few dozen electric light bulbs. In contrast, NASA scientists calculate that a nuclear-fission reactor would give spacecraft a hundred times more power than solar panels.

A nuclear-powered spacecraft could not only operate powerful radars and other remote-sensing instruments but also use its engines to travel more freely instead of relying on a gravitational “sling-shot” that limits the trajectory of existing probes. NASA said an immediate goal of Prometheus was to provide the propulsion to send a spacecraft to planet-sized Jovian moons—Callisto, Ganymede and Europa—which may harbor life beneath their icy surfaces. The first candidate for nuclear propulsion, the Jupiter Icy Moons Orbiter (JIMO), is unlikely to be launched before 2011 because of the time needed to build the spacecraft.

Space Tourism via the Amazon
Space Adventures, the company that brokered jaunts into space for a pair of millionaires, has announced the first mission intended solely for tourists. The Virginia-based firm has paired with the Russian Aviation & Space Agency, and RSC Energia, Russia’s leading aerospace company, to fly two tourists simultaneously to the international space station on a Soyuz spacecraft. About a dozen people have applied for the two civilian seats on the proposed flight, but hitching a ride won’t come cheap—$20 million per seat. Unlike the previous flights of American businessman Dennis Tito and the improbably named South African, Mark Shuttleworth, Space Adventures says the proposed 2005 mission would be for tourists only, with a Russian cosmonaut onboard to operate the spacecraft for the eight to-10-day trip.

Meanwhile, Jeff Bezos, the founder of Amazon.com, has launched his own space program—called Blue Origin—and wants to send tourists into orbit. The brainchild of the dot-com billionaire has a Seattle address and website, which boasts, “We are building hardware, not PowerPoint presentations.” But skeptics argue that it will take more than a billionaire’s intellectual distraction to get fare-paying passengers into space—and safely back again. “I have to say I just didn’t see any evidence that Bezos and Blue Origin had an idea…To be honest…it sounded really wacky,” said Richard Ellis, a Caltech scientist and a former astronomy professor who was briefed on Blue Origin.

It Keeps Going and Going…
An ion engine just like the one that powered the Deep Space 1 spacecraft has set a trouble-free five-year endurance record with no breakdowns or tune-ups required. The engine is a twin of the Deep Space 1 ion engine used successfully during a technology demonstration mission that featured a bonus visit to comet Borrelly. The earth-bound spare had a design life of 8,000 hours, but researchers kept it running for almost five years, from 5 Oct. 1998, to 26 June 2003, in a rare opportunity to observe its performance and wear at different power levels in a vacuum.

While the engine was still running smoothly, the test was terminated early to allow rocket scientists to inspect engine components. In particular, inspection of the thruster’s discharge chamber is critical for mission designers of the upcoming Dawn mission to Vesta and Ceres, two of the largest asteroids in the solar system. Despite five years of near continuous thrusting, the chamber “was in good condition,” said John Brophy, JPL’s project manager for the Dawn ion propulsion system. “Most of the components showed wear, but nothing that would have caused near-term failure.” According to Marc Rayman, former Deep Space 1 project manager, “This remarkable test shows that the thrusters have the staying power for long duration missions.”

Ion engines use xenon as fuel, the same gas used in photo flash tubes, plasma televisions, and some automobile headlights. Deep Space 1 featured the first use of an ion engine as the primary method of propulsion on a NASA spacecraft. That engine was operated for 16,265 hours, the record for operating any propulsion system in space.

Marriage Made in Heaven
The groom’s attire was a little unorthodox, and the bride never laid eyes on him, but thanks to a Texas law allowing absentee weddings, Russian cosmonaut Yuri Malenchenko and his earth-bound bride were hitched last August in a marriage made in heaven. Though separated vertically by 380 kilometers, the cosmic couple wed in a private ceremony at Johnson Space Center in August. The orbiting groom said his “I dos” via video from the International Space Station.

Malenchenko, who blasted off to the station in late April with American astronaut Edward Lu, quietly arranged to have his tailcoat and wedding ring flown to him aboard a cargo ship that arrived at the station in June. Lu served as his best man during the ceremony, and even performed the wedding march on a keyboard. “It was very sweet,” said Joanne Woodward, the wedding planner. A life-size cutout of the groom greeted guests at the wedding reception decorated with silver stars and mannequins dressed as astronauts. However, the honeymoon will have to wait until after Malenchenko, who wore a bow tie with his blue coveralls, returns to Earth in late October.

The bride, American Ekaterina Dmitriev, said the two had grown closer during their time apart, making them want to marry as soon as possible. “As Yuri was further away, he was closer to me because of the communication we have,” said Dmitriev. “It was a celestial, soulful connection.” Malenchenko and Dmitriev plan a Russian Orthodox wedding sometime in 2004.

Despite headaches for Russia’s space agency, the first marriage ceremony to stray beyond earth’s atmosphere has evoked some national pride in Malenchenko’s native land. “Yuri Gagarin was first in space. We had the first woman in space. We had the first tourist in space. And now this is another first,” said Sergei Gorbunov, Russian space agency spokesman. Still to come, however, is the first cosmic couple to take a real honeyMoon.

Hubble Fate Still Up in the Air
Options for refurbishing or ditching the Hubble Space Telescope, NASA’s groundbreaking orbiting observatory, are up in the air following a report by a team of astronomers on the fate of the twelve-year old telescope. The Hubble was launched in 1990, the first of a series of orbiting observatories, and is now nearing the end of its expected lifetime. The U.S. space agency plans to replace it with a more advanced instrument, called the James Webb Space Telescope, at the start of the next decade.

Originally, NASA planned to extend the life of the Hubble by servicing it with a space shuttle mission in 2005 or 2006. That mission would have allowed the telescope to keep working until about 2010. However, those plans were dashed by the grounding of the shuttle fleet after the Columbia accident in February, and by the need, once shuttles resume flying, to continue building and servicing the International Space Station.

In its report, the committee of astronomers outlined three alternatives for Hubble’s fate: two Hubble servicing missions, one in 2005 and one in 2010 “to maximize the scientific productivity” of the telescope, or a single servicing mission in 2006 to replace gyros on the Hubble and install improved instruments. On the same mission, astronauts would install rockets that could send Hubble crashing into the ocean once the telescope’s usefulness ends. If no shuttle-servicing missions are possible, the committee recommended that a robotic device be attached to the Hubble to bring it down in a controlled manner.

The options ignored suggestions that the space shuttle retrieve the Hubble and bring it back to Earth as a museum exhibit. Instead, the committee suggested the spent telescope be dumped in the ocean; a sad end for an observatory that has captured almost a half-million images of more than 25,000 astronomy targets.

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