ASTRO: NEO 2014 CU13 The Movie

Near earth asteroid 20114CU13 passed by us March 11 about 5 hours UT.
Since it was forecast (and really was) cloudy at that time I tried for
it just before dawn the night before, March 10. There were some clouds
but they soon cleared. I was able to get 30 minutes of data before dawn
started to brighten the sky. First few frames were dimmed a bit by the
clouds but otherwise it worked well. The asteroid was about 1.2 million
miles from us at the time of the movie and about 1.1 million miles at
closest approach the following night so the difference is rather small.
We had three other asteroids pass by, one only 38,000 miles out the
last few days but all were either clouded out or too far south or lost
in the sun from my view.

2014CU14 was discovered exactly one month ago, February 11, 2014. It is
quite large so it is good it kept its distance. Estimates put it at
about 200 meters in diameter.

The movie consists of 30 one minute frames and covers about 32 minutes
of time as it takes a few seconds to download each frame. The frames
were taken at 1.5" per pixel then downsized to 3" per pixel to reduce
the size of the animation but keep the full frame. Due to the bright
moon not far away the image is rather noisy which greatly enlarged the
file. During the imaging run the mount was tracking on the asteroid
rather than the stars. No alignment of the frames was needed. While
its motion was calculated from orbital data a couple days prior to the
night the earth hadn't perturbed the orbit to any great extent so the
values I used to offset from the sidereal rate were sufficient to keep
the asteroid near the center of the frame. Computers and today's
robotic mounts make such feats rather easy to accomplish. Not long ago
even the pros had a hard time doing this type of tracking. The asteroid
moved about 1 minute of arc per minute of time. So the star trails
pretty well define 1 minute of arc.

14" LX200R @ f/10, 30x1' binned 3x3, STL-11000XM, Paramount ME

Movie is too big for USENET and it's klutzy 7 bit attachments so I've
just provided a link to the animation. The first frame is attached as a
JPG.
http://www.prairieastronomyclub.org/...2014CU13-3.wmv

Rick
--
Prefix is correct. Domain is arvig dot net

Rick,

without the ability of the mount to track on the asteroid that would have
been almost impossible.
It's speed is quite impressive.

Stefan

"Rick Johnson" schrieb im Newsbeitrag
...

Near earth asteroid 20114CU13 passed by us March 11 about 5 hours UT.
Since it was forecast (and really was) cloudy at that time I tried for
it just before dawn the night before, March 10. There were some clouds
but they soon cleared. I was able to get 30 minutes of data before dawn
started to brighten the sky. First few frames were dimmed a bit by the
clouds but otherwise it worked well. The asteroid was about 1.2 million
miles from us at the time of the movie and about 1.1 million miles at
closest approach the following night so the difference is rather small.
We had three other asteroids pass by, one only 38,000 miles out the
last few days but all were either clouded out or too far south or lost
in the sun from my view.

2014CU14 was discovered exactly one month ago, February 11, 2014. It is
quite large so it is good it kept its distance. Estimates put it at
about 200 meters in diameter.

The movie consists of 30 one minute frames and covers about 32 minutes
of time as it takes a few seconds to download each frame. The frames
were taken at 1.5" per pixel then downsized to 3" per pixel to reduce
the size of the animation but keep the full frame. Due to the bright
moon not far away the image is rather noisy which greatly enlarged the
file. During the imaging run the mount was tracking on the asteroid
rather than the stars. No alignment of the frames was needed. While
its motion was calculated from orbital data a couple days prior to the
night the earth hadn't perturbed the orbit to any great extent so the
values I used to offset from the sidereal rate were sufficient to keep
the asteroid near the center of the frame. Computers and today's
robotic mounts make such feats rather easy to accomplish. Not long ago
even the pros had a hard time doing this type of tracking. The asteroid
moved about 1 minute of arc per minute of time. So the star trails
pretty well define 1 minute of arc.

14" LX200R @ f/10, 30x1' binned 3x3, STL-11000XM, Paramount ME

Movie is too big for USENET and it's klutzy 7 bit attachments so I've
just provided a link to the animation. The first frame is attached as a
JPG.
http://www.prairieastronomyclub.org/...2014CU13-3.wmv

Rick
--
Prefix is correct. Domain is arvig dot net

The Paramount with The Sky 6 makes it very easy. Just hit the button to
add orbit offsets to the tracking rate and it makes the calculations.
It does turn off if you give any other command to the mount and the
button is on a menu I have to pull down so I have to center a tad ahead
of the asteroid then find the menu and hit the button. Other than that
task its simple to do. Will track satellites the same way but since it
doesn't go through the meridian that's not all that useful. I've not
tried it.

Rick

On 3/17/2014 4:28 PM, Stefan Lilge wrote:
Rick,

without the ability of the mount to track on the asteroid that would
have been almost impossible.
It's speed is quite impressive.

Stefan

"Rick Johnson" schrieb im Newsbeitrag
...

Near earth asteroid 20114CU13 passed by us March 11 about 5 hours UT.
Since it was forecast (and really was) cloudy at that time I tried for
it just before dawn the night before, March 10. There were some clouds
but they soon cleared. I was able to get 30 minutes of data before dawn
started to brighten the sky. First few frames were dimmed a bit by the
clouds but otherwise it worked well. The asteroid was about 1.2 million
miles from us at the time of the movie and about 1.1 million miles at
closest approach the following night so the difference is rather small.
We had three other asteroids pass by, one only 38,000 miles out the
last few days but all were either clouded out or too far south or lost
in the sun from my view.

2014CU14 was discovered exactly one month ago, February 11, 2014. It is
quite large so it is good it kept its distance. Estimates put it at
about 200 meters in diameter.

The movie consists of 30 one minute frames and covers about 32 minutes
of time as it takes a few seconds to download each frame. The frames
were taken at 1.5" per pixel then downsized to 3" per pixel to reduce
the size of the animation but keep the full frame. Due to the bright
moon not far away the image is rather noisy which greatly enlarged the
file. During the imaging run the mount was tracking on the asteroid
rather than the stars. No alignment of the frames was needed. While
its motion was calculated from orbital data a couple days prior to the
night the earth hadn't perturbed the orbit to any great extent so the
values I used to offset from the sidereal rate were sufficient to keep
the asteroid near the center of the frame. Computers and today's
robotic mounts make such feats rather easy to accomplish. Not long ago
even the pros had a hard time doing this type of tracking. The asteroid
moved about 1 minute of arc per minute of time. So the star trails
pretty well define 1 minute of arc.

14" LX200R @ f/10, 30x1' binned 3x3, STL-11000XM, Paramount ME

Movie is too big for USENET and it's klutzy 7 bit attachments so I've
just provided a link to the animation. The first frame is attached as a
JPG.
http://www.prairieastronomyclub.org/...2014CU13-3.wmv

Rick


--
Prefix is correct. Domain is arvig dot net