Thanks to the kind efforts of
Andrea Pelloni, Roberto Haver, and Fabio Anzellini, an Italian
version of this site is also available
- Level Two Menu
- Specifying attributes of, and executing operations on, the subject minor
planet
For several
operations (e.g., processing visual magnitude data, looking for known bodies
whose positions agree with the observations of the subject minor planet), it is
critical that CODES understand whether the subject minor planet is a comet or
an asteroid.
Thus, this
designation should be made immediately upon creating a new minor planet.
From the Level Two
Menu, simply click on "Designate"; on the resulting frame, select
whether the minor planet is a comet or asteroid, then click on
"Submit".
The designation
being made, CODES will save the data to disk and return to the Level Two Menu.
From the Level Two
Menu, simply click on "Add". From the resulting frame, the user can
then select from the following options:
Simply click on
"Optical". The user will then encounter three successive frames:
The first frame
allows the user to specify the UTC date of the optical observation, the
astrometric right ascension and declination (with uncertainties), the visual
magnitude, and the fundamental catalog/epoch to which the observation refers.
Note: CODES supports observations and predictions for the
range 1900-2200.
The second frame
allows the user to specify either the MPC observatory code, or the geodetic
latitude, east longitude, and altitude, from which the observation was made.
Additionally, the user may check a box telling CODES to generate default Earth
Orientation Parameters; the third frame would then be skipped.
Note: For typical optical observations, where
uncertainties are on the order of 0.1 arc seconds or greater, the default
EOPs generated by CODES are sufficient.
The third frame
allows the user to specify the Earth Orientation Parameters (EOPs) at the time
of the observation. EOPs allow calculation of the ultra-precise location of the
observer. These EOPs include the x and y coordinates of the Celestial Ephemeris
Pole, the values of UT1-UTC, and the Celestial Pole Offsets dPsi and dEpsilon.
(Note that these EOPs are required for four dates surrounding the observation;
Besselian interpolation is then used to approximate the values of the EOPs at
the precise observation time.) Additionally, the user must specify the number
of leap seconds and the Earth's angular velocity at the time of observation.
Note: The option to specify EOPs for optical observations
will allow future support of more precise astrometric techniques.
Note: An excellent source of EOPs is the International
Earth Rotation Service (IERS) web site.
IMPORTANT: Do not leave any data fields blank! This can cause a
run-time error.
IMPORTANT: From either of the three input frames, it is possible to cancel
the input function and return to the Level Two Menu; the new
(and incomplete) observation will be deleted.
When complete,
CODES will save the data to disk and return to the Level Two Menu.
Simply click on
"Radar". The user will then encounter three successive frames:
The first frame
allows the user to specify the UTC time of observation, whether this
observation is a delay or a doppler measurement, the measurement and its
uncertainty, and the transmitter frequency.
Note: CODES supports observations and predictions for the
range 1900-2200.
The second frame
allows the user to specify the location of both the transmitter site and the
receiver site. In each case, the user may either select one of several common
radar sites (in which case the lat/long/alt data fields may safely be left
blank), or select "other" and specify the geodetic latitude, east
longitude, and altitude of the transmitter/receiver.
The third frame
allows the user to specify the Earth Orientation Parameters (EOPs) at the time
of the observation. EOPs allow calculation of the ultra-precise location of the
observer. These EOPs include the x and y coordinates of the Celestial Ephemeris
Pole, the values of UT1-UTC, and the Celestial Pole Offsets dPsi and dEpsilon.
(Note that these EOPs are required for four dates surrounding the observation;
Besselian interpolation is then used to approximate the values of the EOPs at
the precise observation time.) Additionally, the user must specify the number
of leap seconds and the Earth's angular velocity at the time of observation.
Note: For radar data, accuracies of 0.1 microsecond or 30 meters
are typical. My sensitivity analyses indicate that 1 meter accuracy could be
supported without interpolating the published EOPs. However, the
state-of-the-art is advancing so rapidly that I feel it prudent to accommodate
future radar technology (up to 0.1 meter accuracy); thus, second-order
interpolation of the EOPs is used.
Note: An excellent source of EOPs is the International
Earth Rotation Service (IERS) web site.
IMPORTANT: Unless otherwise noted, do not leave any data fields
blank! This can cause a run-time error.
IMPORTANT: From either of the three input frames, it is possible to cancel
the input function and return to the Level Two Menu; the new
(and incomplete) observation will be deleted.
When complete,
CODES will save the data to disk and return to the Level Two Menu.
The Minor Planet
Center (MPC) provides free web-based electronic circulars
containing formatted tables of new observations of recently discovered and
high-interest minor planets. The MPC also provides an Extended Computer Service
called MPCOBS which enables users to extract files containing all observations
of a specific minor planet.
With some help from
the user, CODES can batch-process the entire set of observations contained in
each of these files, thus avoiding the need for manual input.
Simply click on
"MPC". The next frame will ask the user to save the MPEC or MPCOBS
file (from the web browser o