Can the Heavens Wait?
{Why dumping Hubble is a bad idea}

January 2003

More than four thousand meters above the Pacific, the world’s biggest observatory complex dominates the summit of Mauna Kea in Hawaii. Among other instruments at this site are Kecks I and II, the two largest optical telescopes in the world; each possesses a mirror that is ten meters wide. Mauna Kea is without question one of the nation’s leading scientific research facilities.

One can therefore imagine the public outcry which would result if the University of Hawaii, which runs Mauna Kea, was to announce one day that its telescopes would be demolished due to budgetary constraints. The maintenance tab is high for all those white domes under the stars, the University might say in this outrageous scenario, and other programs require increased funding. Picture the demands that money be found for this admirable facility, the sit-ins by astronomers threatening to chain themselves to their telescopes, the calls for the resignation of the incompetent provosts who would chop down the forest for the trees, and so forth.

An outlandish fiction? In the case of Mauna Kea, thankfully yes. But virtually the same thing is happening to another, even more valuable observatory – the Hubble Space Telescope. Hubble has been called the single most important instrument in the history of astronomy. Because it orbits outside the Earth’s atmosphere, it’s capable of seeing things better than even much bigger ground-based instruments. Hubble is also almost certainly the most popular scientific tool in history. According to a Science News survey of all science stories published world-wide, Hubble coverage in 2002 comprised a whopping 33% of all NASA-related articles. Perhaps not surprisingly, given that astronauts have been leashed to low Earth orbit for three decades, stories about crewed spaceflight amounted to only 9%; the Hubble gets over three times as much press – and for an operating cost of only 2% of NASA’s annual operating budget.

Hubble’s awesome pictures have served as a source of inspiration to millions. Its famous “Pillars of Creation,” in which glinting new stars are visible emerging from coruscating stalagmites of hydrogen in the Eagle Nebula, is one of those rare images comparable in its visceral impact to Apollo 8’s canonical “Earthrise over the Moon.” In its revelatory Deep Field pictures, the earliest visible galaxies can be seen careening at the edge of space-time like candy-colored pinwheels. These and other pictures confirm that Hubble is something like our national time machine – a wunderkammer capable of peering back to epochs far predating the formation of the Earth. It has provided a new sense of both our position and our possibilities in a dazzlingly vast universe.

Despite all this, just days after President Bush unveiled an ambitious new space initiative in mid-January, NASA announced it would drop plans to send a shuttle on one of its periodic Hubble servicing missions. The decision spells an early demise for the observatory, regardless of the fact that more than $200 million dollars of new instruments, batteries and gyroscopes have already been built. In the past such missions, which have the virtue of displaying just how invaluable crewed spaceflight can be in assisting pure scientific research, have had such a rejuvenative effect on Hubble that a new telescope was in effect created. As Steven V. W. Beckworth, director of the Space Telescope Institute, puts it, “A servicing mission to Hubble is comparable in science value to the launch of a new satellite and should be judged as such.”

NASA had already been planning to cut Hubble’s mission short by 2010, after one more shuttle visit, although the telescope could stay productive for much longer with servicing. Its decision means that Hubble will most likely expire by about 2007. The agency argues that it needs to make room in its budget for the next-generation Webb Space Telescope, tentatively scheduled for launch in 2011 – a cutting-edge spyglass which will survey the sky in the infrared spectrum, however, not in visible light like Hubble. Apart from losing an expensive national asset prematurely (at $1.6 billion, Hubble is comparable in cost to a shuttle), this means that there will be a period with no functioning space telescopes, and that there will be no chance to use Hubble and the new Webb telescope in tandem.

There’s an unsettling aspect to the agency’s use of several convenient pieces of cover to make it less likely that its decision will be questioned. Two are obvious: the wave of public interest that its Mars rovers have brought to NASA, and the complex challenges of the new Bush initiative, which mandates that resources be directed towards crewed missions to the moon and beyond. Interest in the Mars robots, by itself a reassuring indicator of a latent fascination with space exploration, also provides a handy smoke-screen for the agency; in other circumstances the premature end of its most popular perennial would certainly be criticized. And with many new objectives now crowding its plate, including the creation of a much-needed vehicle capable of taking astronauts out of Earth orbit, NASA clearly needs to trim as much fat as possible. The problem is that Hubble really can’t be called flabby: in fact the number of published scientific papers resulting from its observations ratchets ever upwards, reaching a record-breaking 3,600 in 2002. As Beckworth commented, “We are aware of no other NASA mission which is more than a decade old, yet grows more productive every year.”

One of NASA’s reasons for not servicing Hubble is particularly problematic, because it exposes agency management to accusations of disingenuousness: safety. It’s true that Hubble’s orbit is sufficiently different from that of the International Space Station that if a servicing shuttle were to experience a problem in flight similar to the one that eventually destroyed Columbia, it wouldn’t be able to use the ISS as a life-boat. But advertising this fact to help forestall a Hubble mission, astronomers suggest, is a sophism designed to quell congressional criticism. NASA has three working shuttles left. When they return to flight, they will have a large back-log of ISS-related tasks to perform. It has already been established that if Columbia’s condition had been known while in orbit, another shuttle could almost certainly have been prepared for a rescue mission in time. Given that the recertified shuttles will almost immediately resume flights to the ISS, why couldn’t two be readied simultaneously – one to visit Hubble and the second to serve as a rescue or replacement parts vehicle (for example, bearing tiles “cannibalized” from the garaged orbiter) in the unlikely event of a problem with the first? (In fact the Columbia Accident Investigation Board mandated exactly this step.) Upon the uneventful return of the Hubble mission, the second could blast off to the ISS, with little or no extra money spent. Anyway, NASA has just been ordered to return to the moon and forge on to Mars – missions far riskier than a Hubble trip. One is left wondering what could possibly serve as better training for these complex tasks.

Another no less disturbing aspect of NASA’s decision is its loopy financial logic. The agency is rightly concerned with how to pay for Bush’s new space goals, and a Hubble mission costs over $500 million. But failure to visit the telescope, which is subject to incremental orbital decay, and boost it to a higher altitude using the shuttle means that a robotic rocket will have to be designed and built to fly there. It’s supposed to attach itself and bring the telescope safely down into the ocean; Hubble is too large to risk uncontrolled reentry. And here lies the fiscal absurdity: the price of that rocket is estimated at 300 million – but given that Hubble wasn’t designed for automated docking, new technology will have to be developed, and this cost could well rise. Combine that with the 200 million in new gizmos already built for Hubble and you get a woeful picture, in which not spending 500 million to service the instrument, thus adding many more years to its life, means that the same total or more will have to be wasted in grounded instrumentation and a rocket to bring the telescope crashing down! (A servicing mission could attach rockets for eventual controlled reentry far more easily and cheaply than a robotic mission.)

In fairness to NASA, it now has a mission that’s paradoxically both bracingly enviable and the reverse. It has been directed to in effect write a new chapter in human history, and boldly go where no one has ever split an infinitive before. That’s the enviable part. But it’s apparently supposed to do this on the cheap. Although it might sound reasonable to ask that the agency simply find a less scientifically valuable program to cut, under these circumstances that isn’t so easy. Given the continuing good health of the nation’s flagship Great Observatory, and the outrageousness of dumping it in the drink for essentially the same price it would take to keep it peering into the cosmos, another solution presents itself. It’s similar to what might have been appropriate if the University of Hawaii had in fact gone off its rocker and decided to dynamite Mauna Kea: a congressional grant, in this case to give Hubble two more shuttle missions and another decade of discoveries. A billion dollars might not be peanuts, but it would be of incalculable value in our continuing quest to understand the universe and our place within it.

-- Michael Benson
Ljubljana, Slovenia
January 26, 2004