This is simbad2k. To query for a sidereal object, use /&lt;object&gt;?target_type=&lt;sidereal or non_sidereal&gt;. For non_sidereal targets, you must include scheme, which can be either mpc_minor_planet or mpc_comet.Ex: <a href="/103P?target_type=non_sidereal&scheme=mpc_comet">/m51?target_type=sidereal&scheme=mpc_comet</a>