In Search Of the Vulcans

jonerik writes: "No, not those Vulcans. The BBC has this article on the Southwest Research Institute's (SwRI) search for the Vulcanoids, a belt of perhaps a few hundred small asteroids (perhaps between one and 25 kilometers in diameter) theorized to exist inside of Mercury's orbit around the sun. Because of their closeness to the sun and small size, the asteroids - if they exist - would be hard to observe from the ground. To that end, a NASA F/A-18 is being used to conduct a search 'of the twilight sky near the Sun that is far darker and clearer than can be obtained from the ground,' says Dr. Dan Durda of SwRI. According to the article, 'The camera used in the latest search...is trained on the region of space close to the Sun after the star has dipped below the Earth's horizon. The camera grabs twilight images at a rate of 60 frames a second.' The researchers hope to have a better idea of whether or not the Vulcanoids exist in another month or two."

Comments

Re:Hey

[dpp]

I thought longer exposure times, sky conditions and a stable camera were key in astrophotography. If I'm wrong please correct me, but mounting a camera on an f-18 dosen't sound like good practice.

According to the SWUIS page the 60 fps rate of the camera is used for jitter compensation, so presumably the fast frame rate is quicker than the characteristic timescale of the aircraft motions.

An aside: for the larger aircraft-borne telescopes like the Stratospheric Observatory for Infrared Astronomy (SOFIA) the telescope is "as stable as a mountaintop telescope sitting on a 10 meter cement foundation" according to the FAQs. From that page:

So how do you do this? First, you isolate the telescope from the airplane by mounting it on a spherical pressurized oil bearing. The plane shakes and quakes, but the telescope doesn't feel it. Second, you direct the wind away from the telescope by shaping the side of the airplane so as to deflect it, and install a little deflector fence on the edge of the telescope cavity as well. Third, you stabilize the telescope against sudden motion (wind does get through) by spinning three orthogonal gyroscopes which are rigidly attached to the structure, and fourth, you steer the telescope so as to keep it steady, by tracking a distant star and giving the telescope magnetical nudges to point it toward a fixed direction.

The search for Planet Vulcan

[dexter riley]

The SEDS Nine Planets website has a nice review of the search for an intra-Mercurial planet (to be called, surprise surprise, Vulcan), back before Einstein explained away the discrepancies between Mercury's predicted and actual orbits.

-dexter "still looking for planet x" riley