We recently compared NASA’s $8 billion James Webb Space Telescope to the European Extremely Large Telescope, which will provide 6 times the resolution at 1/6 the price.

Soon afterward, we received a note from former NASA scientist-astronaut Ed Gibson, who operated the Apollo Telescope Mount during the Skylab 4 mission. Dr. Gibson thought we had understated the case: “The E-ELT has a second advantage over the JWST’s lower resolution and light collection area; it can be serviced as required; the JWST, unlike the HST, cannot be serviced insitu.”

To be fair, NASA is studying some ideas for in-space servicing of JWST, using the Orion capsule and Space Launch System. Impartial observers do not consider those ideas to be credible, however. An Orion mission to the Earth-Sun L-2 point, where JWST is to be located, would cost a minimum of $2 billion, for the launch alone. That assumes Orion and SLS are already developed and available when they are needed.

Beyond the matter of cost, there are all sorts of technical obstacles. The JWST is not designed for in-space servicing. The Orion capsule is not designed to provide a stable work platform for servicing missions. The L-2 point is located 1.5 million miles from Earth. At that distance, the round-trip time lag for communications is 16 seconds, limiting the ability of mission control to provide ground support during EVAs.

The United States needs to develop its ability to do in-space servicing in Low Earth Orbit and, eventually, in deep space. That ability needs to be developed in a sensible manner, however. Astronauts have been doing in-space maintenance and repairs since Skylab. The challenge now is to make in-space servicing cost-effective. Some will say robots are the answer, but robots are not a magic bullet. The 16-second time lag for communications at L-2 is an impediment for humans but a killer for robots. We need to develop a range of servicing methods, both human and robotic, but we also need to develop the supporting infrastructure including low-cost transportation to orbit, low-cost transportation in orbit, and appropriate, cost-effective on-orbit facilities. Most of this infrastructure will be developed commercially in the decades to come.

For now, it appears that NASA is trying to tie two expensive programs – JWST and Orion/SLS – together. That’s a strategy NASA has employed successfully in the past, with programs like the Space Shuttle and Space Station. It’s a dangerous strategy, however, which makes it harder for Congress to cancel one program but drives up overall costs. If Congress ever becomes serious about saving money, both programs will be in danger.

European astronomers have discovered a planet with about the mass of the Earth orbiting the second star in the Alpha Centauri system. It is the smallest exoplanet yet discovered around a star like the Sun. The planet was discovered using the 3.6-meter telescope at the European Southern Observatory’s La Silla Observatory in Chile.

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Sky and Telescope reports that the United Kingdom Infrared Telescope (UKIRT) is in danger of being shut down if its owners can’t find a buyer to keep it in operation.

The UK Infrared Telescope is not exactly a backyard scope. The 3.8-meter (149-inch) instrument is the second-largest infrared telescope in the world and the largest in the northern hemisphere.

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This summer, the European Southern Observatory Council approved construction of the European Extremely Large Telescope. The E-ELT, to be sited on the Cerro Armazones mountain in the Atacama Desert of Chile, will be the largest optical/infrared telescope ever built. The primary diameter will be 39.3-meter (129-foot). Rather than a single mirror, the primary element will be an array of 798 1.4-meter (55-inch) mirrors.

The estimated cost for the mega-telescope, which is expected to see first light in 2022, is €1.055 billion ($1.36 billion at current exchanges rates).

American taxpayers should take note. That price is less than 1/6 the cost of NASA’s infrared James Webb Space Telescope (assuming JWST does not suffer any further cost overruns). Yet, the angular resolution of E-ELT at mid-infrared wavelengths will be six times better than JWST.

As we noted recently, advances in ground-based infrared astronomy are one reason why many astronomers are strangely unexcited about the JWST. The E-EELT is a good example of that.

The Europeans have also shown the willingness to sacrifice ultimate performance for the sake of cost-effectiveness. The size of the primary element was reduced from 42 meters, as originally planned, to save money and speed construction. This reduced the cost by 18%, from €1.275 billion to €1.055 billion, at the cost of 13% lower light sensitivity. Yet, astronomers are happy with the tradeoff because it enables the instrument to get built.

The construction plans for this telescope require almost 800 mirrors to be fabricated, then shipped separately to the top of the 3,064-meter (10,052-foot) peak.

There are risks in that plan, which will require a massive number of trucks. Perhaps one of the trucks will accidentally drive over a cliff, before the project is complete. With that many trucks, accidents are almost inevitable. Then, all of those mirrors must be assembled by workers under difficult conditions, at an altitude almost two miles above sea level. Working in parkas and mittens is uncomfortable. Studies show that workers in comfortable, air-conditioned factories at sea level are more efficient. Instead of trying to complete a massive construction project at that altitude, wouldn’t it be better to fabricate one huge monolithic mirror and develop a supertruck to transport it?  Of course, no one has proposed such silliness. Yet, that’s the same “logic” used to justify developing superheavy lift rockets for space telescopes and other large space structures. We know how to make tradeoffs and compromises for the sake of cost-effectiveness on Earth, but never seem to do it for space projects.