Figure 4.
Observations of 2 Pallas
with GPI recorded
with the J, H, and K1
gratings on March
22 during VC2 at
high airmass (>1.5).
The asteroid with an
angular diameter of
0.7” is well-resolved
and displays a potato
shape typical for a
500-km asteroid. The
surface remains mostly
featureless but detailed
analysis may confirm
small difference in
composition between
the north and southern
hemisphere of the
asteroid. No moons
with a diameter
larger than 0.5 km
and at less than 1.2”
were seen. Pallas
was observed with
the same geometry,
~7.8h later with the
SOFIA telescope and its
mid-IR spectrograph
called FORCAST. The
combination of these
two set of observations
could reveal the
composition of this
asteroid.
14
tion in the 60 hertz vibration that the CCRs
were propagating to the rest of the instrument. Synchronizing the controllers reduced
the intensity of the vibration and completely
eliminated the beating effect caused as the
controllers drifted in and out of phase.
Following lab characterization, GPI was given
the green light to recommence on-sky verification and commissioning, beginning March
20, 2014. Gemini prepared “Verification and
Commissioning” contracts with Stanford University, Lawrence Livermore National Laboratories, “Search for Extraterrestrial Intelligence”
Institute, University California Berkeley, University California