KBO encounters Options

[xtruel]

Hi,

I’m regular follower of NH and I’m also interested in the 2nd leg of the mission, i.e the 2016+ KBOs encounters. Does anyone know when operations about this leg (starting with searching objects of interest with HST or some other earth-based means, I suppose) are expected to begin ?

[hendric]

John,
Thanks for the update! I was curious, are you using a 16 or 32 bit FITS workflow? It seems like some of the images are suffering from a weird clipping like the subtraction was done on signed data but the conversion to an image format was done on unsigned data. Maybe you could provide a couple of sample images and we could hold a contest for the best subtraction algorithm.


You said binary KBOs are likely to still be point sources on these images, what about binary asteroids/centaurs?

Also, is there a fixed image scale for these pictures, or do they vary?

[john_s]

John,
Thanks for the update! I was curious, are you using a 16 or 32 bit FITS workflow? It seems like some of the images are suffering from a weird clipping like the subtraction was done on signed data but the conversion to an image format was done on unsigned data. Maybe you could provide a couple of sample images and we could hold a contest for the best subtraction algorithm.

I can pass on this question to Marc Buie, who is doing the subtraction algorithms, but I'd be very surprised if there were artifacts related to bit clipping. The subtraction of different point-spread functions, even after convolution to try to match them, can produce some pretty strange artifacts though. Maybe you could PM an example to me...

As to subtraction algorithms, part of the trick is to have something that works automatically on hundreds of different image pairs- we don't have the resources to manually fine-tune every example. However some preliminary tests on our 2011 data suggest that we'll be able to do better subtractions than we've achieved on the 2004 data- we'll see when we turn the crank on the full data set.

You said binary KBOs are likely to still be point sources on these images, what about binary asteroids/centaurs?

Probably the same- again most binary asteroids have been discovered using adaptive optics or Hubble.

Also, is there a fixed image scale for these pictures, or do they vary?

All are the same scale, 0.2"/pixel in the case of SuprimeCam on Subaru, which produced all the beta images.

John