Astronomy has entered a new era of mega-telescopes, where even ground-based instruments can cost upwards of a billion dollars. The James Webb Space Telescope is expected to cost more than $8 billion. Obviously, such instruments are well out of the range of citizen scientists. The future for amateur astronomy is not dim, however. Smaller, lower-cost telescopes remain relevant and useful for astronomy.

For this reason, both professional and amateur astronomers should welcome the development of reusable suborbital spacecraft which can carry small telescopes on short-duration missions. These low-cost missions will enable many astronomical experiments that benefit from access to space but do not need (and often cannot afford) a ride to orbit.

Flying telescopes on suborbital spacecraft is not a new idea. In the 1960’s, the X-15 rocketplane flew a number of telescopes for NASA. The NASA Office of Space Sciences sponsored the Ultraviolet Stellar Photography experiment, for example, which photographed Alpha Aurigue, Eta Aurigue, and Rho Aurigue from altitudes above 246,000 feet.

Professional astronomers are already starting to develop astronomical instruments for the new commercial suborbital vehicles. Among the first of these instruments is the Atsa Suborbital Observatory, designed by Dr. Faith Vilas of the Planetary Science Institute and Dr. Luke Sollitt of The Citadel, the Military College of South Carolina. Dr. Vilas recently left her position as director of the MMT (Multiple Mirror Telescope) Observatory to develop Atsa.

The Atsa Observatory is based on commercial off-the-shelf components. The optical component is a 14-inch Celestron Schmidt-Cassegrain telescope, with some modifications to increase its ruggedness. The main sensor will be a commercially available Silver 220 or  Thermovision SC4000 infrared camera. Visiting scientists will have the option of bringing their own sensors, however.

Atsa Observatory suborbital space telescope

Atsa (the Navaho word for “eagle”) will fly on the XCOR Lynx Mark III. It will be controlled during flight by a payload operator in the Lynx’s right seat. Having a human in the loop means that researchers won’t have to spend a lot of money automating their experiments and debugging control software. The Lynx spacecraft will do the coarse pointing of the telescope using its maneuvering thrusters, but a gimbal-drive-motor assembly will do the fine pointing. Atsa will ride in the Lynx’s dorsal experiment pod and be exposed to space by a door during flight. Dr. Vilas says, “The best window is no window.”

Atsa is designed primarily for infrared astronomy at wavelengths that do not penetrate the Earth’s atmosphere. Water in the atmosphere absorbs wavelengths in a wide swath from the near- to mid-infrared. That absorption disappears at altitudes around 100 kilometers. In addition, the ozone layer at 50 kilometers absorbs ultraviolet wavelengths. So, Atsa could be useful for US astronomy as well.

One advantage Atsa has is the ability to study objects which appear close to the sun. Large orbital observatories, such as the Hubble Space Telescope and Spitzer Space Telescope, have limitations on how closely they can be pointed to the Sun. No one wants to take a chance on accidentally burning out a Hubble sensor. If an Atsa sensor were accidentally pointed at the sun, however, it could be quickly and easily replaced. It might not even delay the next flight.

This pointing capability makes Atsa uniquely suited for observations of sun-grazing comets, Aten and inner-Earth asteroids, hypothetical Vulcanoid asteroids, Mercury, and Venus. In addition to their scientific value, these observations can serve the cause of planetary defense by helping to locate potentially threatening asteroids in the “blind spot” near the Sun.

High-altitude aircraft have already been used as observation platforms for near-Sun objects. In 2002, Dr. Alan Stern (former NASA Associate Administrator for Space Science) and Dr. Dan Durda conducted a search for Vulcanoid asteroids by operating the Southwest Ultraviolet Imaging System in the cockpit of an F/A-18 Hornet at 60,000 feet. Stern and Durda are now members of the Suborbital Applications Researchers Group, which is training to fly science missions on suborbital spacecraft. By coincidence, the pilot for those flights was former Shuttle astronaut Lt. Col. Rick Searfoss (USAF-ret.), who is now chief test pilot for XCOR Aerospace. Colonel Searfoss’s experience may give XCOR a competitive advantage when it comes to flying astronomy payloads.

Because it requires the large dorsal pod which is a feature of the Lynx Mark III, the Atsa observatory will not be available for a few years. In the meantime, the Atsa team plans to test the gimbal-drive hardware by flying a smaller prototype device. The Atsa Armrest Camera is being designed and built by students at The Citadel. Development started in summer of 2011, and the four-student team expects to finish it by summer of 2012. The Armrest Camera will be tested on the Lynx Mark I; it will be attached to the payload operator’s seat and take images through the Lynx cockpit window.

Although the Atsa Observatory is being developed by the Planetary Science Institute and The Citadel, the Atsa team intends to make the observatory available to astronomers from all over the world. Does that include citizen scientists as well as professional researchers? Citizens in Space asked Dr. Vlias that question at the Next Generation Suborbital Researchers Conference in Palo Alto. Her answer: “I can’t think of any reason why not.”

It’s even possible that a group citizen scientists might build their own Atsa-like observatory. Apart from the gimbal-drive assembly, the major parts of the Atsa observatory are off-the-shelf. If built by amateurs, this would probably be a six-figure project – not a million-dollar project. Perhaps someone like the X-Prize Foundation or NASA’s Centennial Challenges would put a prize for such an amateur project?

Building a space telescope doesn’t have to be rocket science any more.

Written by Astro1 on March 28th, 2012 , Astronomy, Innovation, XCOR Aerospace

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