What's happening in our universe? In the 400 years since we first started using telescopes, we've been trying to answer this question. The past two decades alone have been dizzying: Planets found outside the solar system, a universe accelerating in its expansion, and hints of the mysterious dark energy and dark matter that make up most of the universe, to name a handful of historic discoveries.
But to see further, we often need to spend big.
There's been much coverage of the more than $9 billion James Webb Space Telescope that will launch in 2018, to probe planetary atmospheres and to look back at the universe's beginnings. What will come next? Looking a bit ahead, the astronomy organization AURA suggests a "High Definition Space Telescope" to launch in 2035, an observatory double Webb's size. But how this would be paid for comes under scrutiny in a new report.
Harvard astrophysicist Martin Elvis' new paper in Space Policy to try to solve what he calls the astronomy "funding wall." Our hunger for greater telescopes in X-ray emissions alone, he argues, has made the cost of this mission type increase 20 times in the past generation. (Yes, that's after adjusting for inflation.) Moreover, space missions often go over their budget before launch.
"At some point the costs are more than a government can abide," he wrote. "Particle physics hit its funding wall in the U.S. when the Superconducting Super-Collider, already far along in construction in Texas, went over budget one too many times and was cancelled. Is astronomy next?"
JWST may already be testing the limits, he added. Its cost growth led to repeated threats of cancellation, but the mission has been replanned to try to avoid this. Elvis said that NASA has a budget of just $5 billion per decade for large new space telescopes. "Each JWST-class mission thus takes 100% of nearly 20 years of this funding line," he said, pointing out the successor mission of the Wide-Field Infrared Survey Telescope (WFIRST) could be similar in cost to JWST.
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He also worries that focusing on a single, large telescope will make NASA's program lose its robustness. Right now we have three "Great Observatories" -- the Hubble Space Telescope, the Spitzer space telescope, and the Chandra X-Ray Observatory -- operating in different wavelengths: visual, infrared and X-ray. We need to study the same object in different wavelengths to properly understand it. The youngest of these telescopes is 13 years old and will eventually fail during JWST's lifetime; JWST is most sensitive in infrared and follow-up observations in X-rays, Elvis argues, would need to wait.
But before worrying overmuch, Elvis proposes a solution: to depend more on the commercial space sector. Think about how much it has changed human spaceflight in the last decade. Now we have regular cargo runs to the International Space Station; in SpaceX's case, occasionally these missions have been able to land their rockets for future re-use. And very soon, SpaceX and Boeing will be sending astronauts aloft on their own spacecraft. What is the prospect for astronomy?
He argues that commercial spacecraft (which are more likely to see cost driven down by competition) would see quick advances in a few areas. Costs in launch, spacecraft and payloads would reduce, mainly because we are making a lot of advances today to reduce the mass hefted to orbit. In space, mass is one of the major costs.
"Cutting spacecraft cost by a factor 2, along with launch costs by a factor 3, would roughly halve the cost of a flagship mission," he said. "This would radically alter flagship mission decisions, by doubling the number that could be launched each decade."
Elvis also argues that as private tourists spend time in orbit, the demand would lower the cost for low-Earth orbit missions and provide more access for astronomers. How this would be done still needs to be worked out (the Bigelow module on the space station has no platform for telescopes, for example.) More locations could open up across the solar system with private lunar landers and asteroid prospectors, too.
You can read about these arguments, and Elvis' vision for spaceflight in the 2020s and beyond as we expand across the solar system, in his paper "What can Space Resources do for Astronomy and Planetary Science?"
Originally published on Discovery News.