Nige C wrote:I follow a lot of the electromagnetic spectrum including light
Unless you're living on top of Mauna Kea where the only ground-based infrared telescope is located, you're missing one important part of the spectrum. I'm waiting to be scheduled for flights aboard the NASA and DLR (the German version of NASA) Stratospheric Observatory For Infrared Astronomy (SOFIA) highly-modified 747SP in 2014 for NASA's Airborne Astronomy Ambassador (AAA) program. The aircraft carries a 17-ton, 10-foot diameter reflector telescope built for the DLR that peers out through a 10 x 12 foot opening to the stratosphere in flight in the port side of the fuselage, aft of the wing. A second pressure bulkhead was installed forward of the telescope, which is in the former aft end of the coach section of the former Pan Am Clipper and United Airlines airliner.
The telescope is balanced on a 3-foot diameter solid steel sphere at the center of the bulkhead with a one-foot diameter optically transparent quartz Nasmith tube passing through it. There are two tertiary planar mirrors on the telescope, one with a sparse gold atom matrix where the atoms are close enough together to reflect far-infrared energy (just above the cosmic background microwave radiation from the Big Bang), but far enough apart to allow visible light wavelengths to pass through.
A second traditional aluminum-coated mirror is about 18 inches behind the first mirror due to the differences in focal length of the two wavelength ranges (those red f-stop numbers on camera lenses are the infrared values). Both energy beams pass through the Nasmith tube to up to four sensor packages positioned on the counterweight on the interior side of the bulkhead and they perform infrared or visible light imaging, spectroscopy, interferometry, energy intensity measurement, etc. About 30 sensors are planned for development over the next couple of decades that the aircraft will be flying, with improved sensitivity, accuracy, etc., as technology gets better.
The AAA program is the closest thing NASA has to the Teachers in Space program that ended when teacher Christa McAuliffe died in the Space Shuttle Challenger explosion. Educators fly aboard the aircraft on collection missions that last about 8 - 10 hours overnight at 45,000 feet and assist world-class astronomers, telescope operators, and mission specialists with collection, processing, analysis, and mission track decisions. We also document the activities for our students and those all over the world via social media, which includes the years of training and preprations leading up to a flight, the missions themselves, and post-flight processing, in-depth analysis, follow-on long-term research, etc. All of the data is recorded on petabytes' worth of removable disk drives (for post-mission research) and there is a massively-parallel high-performance computing system on board that performs near-real-time image and other sensor data processing.
As data is collected and given a quick-look by the astronomers on-board, decisions are made in conjunction with the mission director at their side (who monitor aircraft navigation along the planned track) whether to continue collection or move on to lower-priority targets. Subsets of images and data are also transmitted via the NASA Tracking and Data Relay Satellites (TDRS) to researchers around the world over gigabit-per-second research internetworks so those who can't make a given flight can also make recommendations about continued target collection vs. moving on to the next target.
The sphere in the bulkhead acts as a pivot point to isolate the telescope from small aircraft roll, pitch, and yaw motions, and dozens of truck air shock absorbers around the periphery of the bulkhead that are computer controlled based on multi-axis accelerometer inputs to damp out even miniscule aircraft vibrations and movements. The telescope can remain boresighted on a target the size of a dime at over a mile away, which has been verified by putting the entire aircraft on a shake table and measuring the telescope's stability.
I'll be bringing all of my Pii aboard the aircraft (probably connected to lapdocks), and since they provide TDRS-Internet-connected WiFi for the laptops the crew and researchers bring aboard, I hope to be able to provide access to the Pi community during mission flights. They left the original first-class seating aboard (now over 30 years old as the aircraft was mothballed by United in the early 1990s), so we get to ride in (ye olde) style during takeoff and landing. Pan Am's first class section was in the upper section behind the cockpit and business class was in the forward part of the lower deck, but United swapped them because the windows at the forward-most seats provide views looking directly ahead of the aircraft.
The entire coach section seating was replaced by the telescope, second pressure bulkhead, and consoles for telescope operators, astronomers, and mission specialists. Because the airliner emergency oxygen system was removed from the coach section during conversion, there are masks and hoses at the consoles, but we have to carry portable masks and tanks whenever we're out of our seats. We also have to go through special emergency procedure and evacuation egress training because of modifications to the aircraft.
The program website is at: http://www.nasa.gov/mission_pages/SOFIA/index.html
and the research site is at: http://www.sofia.usra.edu