HIGH PRECISION ASTROMETRY OF
OCCULTATION ASTEROIDS
Sarah Estabrook
Mentor: Dr. William
Owen, Jr.
Consortium for
Undergraduate
Research Experience
(CURE)
Jet Propulsion
Laboratory
CSULA
Table Mountain Observatory
0.6 m Ritchey–Chrétien
telescope
Typical prediction of a
star’s location
•
Beta angle must be greater than
90º
•
Declination must be greater
than -30º
•
Significant number of
background stars
Data Collection
•
Right ascension
and declination
coordinates are
entered
•
Picture taken
•
Coordinates and
temperature,
pressure and
humidity are
recorded
•
Typically two to
five shots taken
for each target
All the images from the
night are then reduced into
precise coordinates of each
target.
•
Update orbital information
•
Determine asteroid’s mass
•
Optical Navigation for use in
certain spacecraft
Antiope—Double Asteroid
http://www.asteroidoccultation.com
Optical Navigation in Spacecraft
Our data and data like ours is used to
assist in the navigation of many longdistance spacecraft
Differenced
Doppler: Another
method of navigation
Saturn’s rings and
Enceladus—one of
many satellites