The designation can be typed in a free format, for example
the following:
N4486
M87
ARP 152
will all point to:
NGC4486
It is also possible to find an object from a positional cross-identification
by following the examples:
nearest:J123049.2+122329
nearest:ned:Virgo A
nearest:[J123049.2+122329,10]
which mean respectively:
the nearest object to the position J123049.2+122329, or
the nearest object to the NED position of object named in NED: Virgo A. The last example specify that the cross-match is done within a radius
of 10 arcsec at maximum (by default it is 90 arcsec).
In these expressions the celestial position accepts several variants, see
documentation.
The recognition of the name, ie. its cross-matching within the database,
depends on the actual database where the request is sent to (HyperLeda or NED).
In other words, in some fortunately rare cases, the same name may be
cross-matched with different objects in the different databases.
HyperLeda recognizes the names as they are often written in the frame of
extragalactic astronomy. That is, it recognizes N4486 to be
NGC4486 which is an ambigous form in a more general context
(see Simbad).
Extended search and list of objects
When searching in HyperLeda it is possible to provide a short list of
objects or a regular expression. This facility is naturally not
allowed when passing a name to a remote service (like NED) or
when searching coordinates or selecting a group of physically associated
galaxies.
To pass a list of names simply use the syntax above and separate each name
with a coma. For example: ngc 4486,nearest:ned:m51.
Extended search can be done using the SQL wildcard character %
to replace any number of characters at any location in the designation.
For example NGC4486% will select NGC4486 , NGC4486A
and NGC4486B. Another example: LGG% will select all the
LGG objects.
Note that extended search is based on the standard spelling of the names,
ie. the spelling HyperLeda uses for each template name. n4486%
will not work...
It is possible to combine lits of names and extended searches. For
example NGC4486%,NGC337%
Principal designation and output spelling
When a designation is returned out of HyperLeda it is chosen out of the whole
list of names descending the hierarchy:
NGC ou IC
UGC or ESO
HD or BD (stars)
PGC (including recent additions)
But avoiding the designations which were found unsafe to cross-correlate with
NED (we are putting large effort to identify names which are ambigously
recognized between the different services and databases).
Each template name in the database has a cannonical form which is used
as a standard format for output. Take examples in the LEDA catalogue.