MPChecker: Minor Planet Checker
Use the form below to prepare a list of known minor planets in a specified
region. Notes on using this form are given at the bottom
of this page.
If you wish to
report the non-functioning of (or errors in) this service, please
use this feedback
form. But ensure that you have seen this note on
computing limits before reporting anything.
We hope that the information given below will be useful in helping you to use
the minor-planet checker form properly.
- The date to be entered is the UT date of your observation (given to 0.1 or
0.01 of a day). The default is now. The date should be within two
years of the present. If you have an older suspect you wish to
check, please contact the
Central Bureau for Astronomical
Telegrams (for novae and supernovae) or the
Minor Planet Center (for minor
- Absolute Position
- The J2000.0 right ascension should be entered in one of the following forms:
HH MM; HH MM.d; HH MM.dd; HH MM SS; HH MM SS.d; or HH MM SS.dd. HH
represents the hours, MM the minutes, SS the seconds and d/dd any decimal
part of the minutes or seconds. Leading zeroes are to be given when
any quantity is less than 10.
The J2000.0 declination should be entered in one of the following forms:
sDD MM; sDD MM.d; sDD MM.dd; sDD MM SS; or sDD MM SS.d. s represents the
sign (`+' or `-', must be given), DD the degrees, MM the minutes, SS the
seconds and d/dd any decimal part of the minutes or seconds. Leading
zeroes are to be given when any quantity is less than 10.
Some examples of valid input follow.
- If the position you wish to search around is 7h13.7m, -14°2', you
would enter `07 13.7' and `-14 02' in the relevant boxes
- If the position is 14h3m8s, +1°48'.3, you would enter
`14 03 08' and `+01 48.3'.
- One or more 80-column observation records can be typed or pasted into the
writable icon. The date of the search, central position and observatory
code will be taken from the observation record. Multiple observations of the
same object will be reduced to a single observation. If you are entering
search fields, rather than observations, ensure that each search field has
a unique "designation".
- Radius of search
- The default setting of 15 arcminutes is thought to be appropriate for the
standard amateur setup, considering the motion of main-belt asteroids. It
may be lowered (down to 5 arcminutes) or raised (up to 300 arcminutes) as
desired. If your
specified radius exceeds the maximum allowable radius, the maximum value will
- Limiting magnitude for search
- The default setting of V = 20.0 may be changed as necessary.
Note that you should set this value to be at least 1.0 magnitude fainter
than your telescope's limiting magnitude to allow for poorly-known minor-planet
- Observatory code
- By default, the calculation is performed for the geocenter (code 500).
If you wish to do the calculations for a specific site, enter the appropriate
observatory code in the writable icon.
- By default all types of objects are searched for. By selecting other
options you can restrict the search to just numbered or unnumbered minor planets
or nearly-numberable minor planets. If this latter option is chosen, the
maximum search radius is 900 arcminutes. It is important to remember when
using the nearly-numberable option that the vast majority of the
nearly-numberable objects are in fact numbered in the next batch of
MPCs. This means that in the period immediately after MPC
preparation there may be very few objects selected.
- Computing Limits
- Note that this form is not intended for checking large number of
fields. There is a maximum limit for CPU time associated with this
script. It this limit is exceeded, the job will be aborted. This prevents
a handful of users running long lists of checks from clogging up the web
server for other users. It is far more efficient to submit large batches
of unidentified observations to the MPC for automatic processing than it
is to try and id the objects through this service.
We are very pleased to acknowledge the support of
Process Software Corporation
and their excellent VMS Web server, Purveyor.
This service runs on the
Foundation Computing Network.