A Ground-Based Scope That Flexes For Better Focus

Steve0987 writes "EE Times Online has an interesting article on a deformable telescope mirror that the University of Arizona has built. It uses 336 magnetic coils to deform the 2 foot secondary mirror and change its shape to compensate for everything from wind blowing against the telescope to atmospheric aberations. It is purported to provide 3 times the resolution of the Hubble telescope. (And you don't have to go into space to fix it."

Comments

--same tech

[zogger]

...same/similar mirror flexing tech they are using for the AirBorneLaser weapon, if I recall correctly.

Good, God. The feedback required.

[robslimo]

Wow!

As a person who's spent about 15 years working with closed-loop controls in computer systems, my mind boggles at the thought of the quantity and variety of feedback devices required to pull this off.

Accelerometers and strain transducers for wind forces, ground vibration and thermal effects on structures at the very least (and multitudes of them, all calibrated with respect to their location, etc). What I'm really having trouble with is how they are managing the thermal and atmospheric compensations.

OTOH, this is an acedemic project and the statement "we have the *potential* to get images that are three times sharper than the Hubble" (my emphesis added) from the article doesn't inspire great confidence in what they may *really* have.

Anyway, I'm off to look for answers at this link to the Center for Astronomical Adaptive Optics at the University of Arizona, the folks doing this work.

What's so great about this telescope?

[bill_mcgonigle]

And that's not sarcasm. I couldn't figure out from the article what's really new and great about this particular telescope. Comparing it to one I've read about, the Starfire:

this vs. Starfire:

The 40-kHz closed-loop adaptive optics (AO) system adjusted the position of 336 points 941 actuator adaptive optics system on its 640-mm (2.1-foot) 3.5 Meter deformable mirror 550 times per second

"This is the first time that anybody has done adaptive optics with a mirror that is an integral part of the telescope itself" said Lloyd-Hart. Primary mirror has actuators ...winds of up to 30 mph had no effect on the final image. "Closing the feedback loop is something that nobody else in the world has -- feedback enables us to make our adjustments very, very precisely, because of our constant stream of position feedback," said Lloyd-Hart. Wind buffeting is reduced by the telescope's very stiff structure and high-torque motors and by angular acceleration sensors which control fast-steering mirrors designed to optically cancel out wind induced jitter.

I'm just a layman who likes reading about telescope technology, but it sure looks like they're making claims of being first when they aren't. Still, the Air Force is funding this, and they have a telescope that can image a basketball at a thousand miles, so there's obviously something good here.

Is it the 550Hz sampling rate? Maybe it's the first one available to civilian astronomers? Does anybody know?