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Discoveries, Credit and Naming

This page covers nightly observation coverage, discovery procedures, how credit is assigned and the naming process for minor planets.

What about coverage on a single night?

You should always supply at least two observations of each object on each night. If you are observing objects in dense starfields, you should plan your observing session with this recommendation in mind.

If you are stacking images, try and ensure that you produce at least two stacks, remembering that the stacks have to be independent, so an image cannot be used in more than one stack. If you can produce only one stack, ensure that the observation is marked as a stack (for 80-column format this means a K in column 14, for ADES this means including a <notes>K</notes> field for each stacked observation). If you produce more than one stack, mark the observations as stacked unless there is another note you wish to use. If you are observing at a site that uses codes to distinguish between different programs, the "K" should appear on the submitted observation, but will be replaced by the program code during processing.

Two-nighter vs. single-nighter new objects

There is no difference between submitting single night or multiple nights of observation of a "new" object. It is therefore recommended that you report observations of potential new objects nightly, ensuring that each object has a unique designation on each night.

What if I can't follow up a new discovery?

If you have observed a new NEO, please submit the observations to the MPC (see also How do I report my astrometry?).

If you have observed a new MBO on one night and you are not able to obtain a second night within a week or so, you should report the tracklet anyway.

The observations will be subject to the normal checking procedures of the Minor Planet Center (see Do I need to identify objects?):

  • If the object is confirmed as a new NEO, it will go on the NEO Confirmation Page and it may get follow-up from other telescopes.
  • If the object is not an NEO, but it is identified with a known MBO, then the observations will be published.
  • If the object is not an NEO and it cannot be identified with any known objects, then the observations are sent to the Isolated Tracklet File (ITF). ITF is regularly checked against new orbits and matches are extracted and published under the assigned designations.

If you wish someone else to follow up your new discovery, you may use the New Object Ephemeris Generator to generate ephemerides to enable your colleague to find the object after the first night.

If someone does follow up for your new objects, you will get credit for the discovery even if you have obtained only one night's observations. However, there is nothing preventing your colleague from getting two nights on your new object and then reporting it to us as a new object. In such a case, credit will be given to your colleague. For this reason, you should not distribute observations of the new object and you should only send ephemerides to colleagues that you trust (see also Who gets credit when single nighters are linked?).

When should I mark a discovery?

Submitters may mark an observation record to indicate the discovery observations of an unidentified object.

In 80-column format, the discovery asterisk is placed in column 13 of the observation record. In ADES format, the discovery asterisk is indicated by including a <disc>*</disc> field for the discovery observation.

It is permissible for there to be no discovery asterisk/field, in which case the MPC will assume that the chronologically earliest observation is to be treated as the discovery observation. There must not be more than one discovery observation per object (a common error is to mark every observation on the discovery night).

Discovery asterisks/fields on submitted observations must only appear on observations with observer-assigned temporary designations. They must never appear on submitted observations with MPC-assigned designations.

There can be more than one discovery asterisk/field for objects that have not yet been numbered. The MPC will assign the final asterisk/field when the number and the discovery credits are assigned. See also this Editorial Note for a more extensive explanation.

The information is published in the monthly Minor Planet Circulars (MPCs).

How do I get a provisional designation?

New provisional designations are assigned to newly-reported objects that cannot be identified with a known numbered, multi-opposition unnumbered or recently-discovered one-opposition (with or without a general orbit) minor planet.

Note that following the Editorial Note on MPEC 2010-U20 the assignment of a new provisional designation does not mean that you will be credited with the discovery of the object when it is numbered. The afore-mentioned MPEC should be read to see the new rules regarding discovery credit and the grandfathering of old multiple-opposition objects. The use of the terms "discoverer" and "discovery" in this document are to be interpreted according to those rules.

New designations are assigned when we have enough observations to compute a reliable orbit. You may use the online New Object Ephemeris Generator to generate ephemerides to enable you to find the object after the first night.

Who gets credit when single nighters are linked?

The credit for the assignment of a new designation is given to the chronologically earliest observation that is identifiable at the time the designation is to be assigned. If earlier undesignated observations are subsequently located (these will often be isolated observations), the assignment credit does not change.

Note that this linking process requires the earlier observations be on a different night (at least 12 hours separation) and to be of good quality.

What's the best way to get my discovery numbered?

The first requirement for getting your discovery numbered is to ensure that the observations at your discovery opposition cover a sufficient arc to enable recovery at a subsequent or previous opposition. Note that "your discovery" does not imply that this will be the discovery apparition when the object is numbered, if previously-reported observations satisfying the requirements listed in MPEC 2010-U20 are located.

Once identified (or recovered as a result of a direct search), observations should be made on pairs of nights in each of two dark runs at each opposition until the object is numbered. For main-belt objects this can occur after the object has been observed at four oppositions (although this depends on the number and distribution [preferably two nights in each of two dark runs in at least three of the oppositions] of the observations as well as their quality); NEOs can receive a number after two or three well-observed oppositions. In addition, the uncertainty parameter, U, must be less than or equal to two for objects to be numbered. Note that newly-identified multiple-opposition objects are not eligible for numbering: numbering of such objects can only take place after the first multiple-opposition orbit has appeared in the MPCs and after further observations have been reported (these can be at the latest opposition, or at an earlier or subsequent opposition). The selection of objects for numbering is an automatic process performed just before the preparation of each batch of MPCs. There is no need to ask us "What do I need to do to get such-and-such numbered?". Simply follow the guidelines above and the object will be numbered when it is ready.

When can I name my discovery?

Asteroid naming is handled by IAU Working Group on Small Body Nomenclature (WGSBN) and not by the MPC. We encourage users to visit the WGSBN website for all matters related to the naming (and associated citation) for all minor planets and comets.

The MPC is not responsible for naming the natural satellites of planets. Naming is handled by the IAU Working Group Planetary System Nomenclature.

Just for sake of clarity, we report the main information about the asteroid naming process:

If you need more information about how to write the citation and submit the name, what names are acceptable, how long it takes for the name to be approved, please contact directly WGSBN, using their contact email address contact@wgsbn-iau.org.