Nomenclature of Interstellar Objects and Stars I posted this question on the space exploration SE but people recommended that it would be more on-topic here. Could someone please help by giving some definite laws of nomenclature for celestial objects, like the provisional names given before a proper name is decided... I am copy-pasting the question here:
I tried searching the answer to this on Google for hours and visited the IAU website as well, but it didn't really clarify my doubt. I was reading about Black Widow Pulsar, which is an &quot;eclipsing binary millisecond pulsar in the Milky Way&quot; and after its common name, in brackets is given PSR B1957+20. How is this named? What nomenclature rules are used? Was this the provisional name given before it was named Black Widow Pulsar or is this the scientific name of the neutron star?
This is the case with most interstellar objects and stars. Like Ultima Thule has another name 486958 Arrokoth? Is this a scientific name? Please explain what nomenclature conventions are used to name the asteroids and stars.
Names are common enough for solar system bodies, but generally stars don't have names, they have identifiers from various catalogues.
In the case of Pulsars. they are named by their location in the sky.  Just like Earth has longitude and latitude, every point in the sky has a &quot;right ascension&quot; and &quot;declination&quot;.  Due to the slow movement of the Earth's axis, to identify the location in the sky you also need to mention a date, though you can look up the positions of stars in 1950 (B1950) or 2000 (J2000). Also, for historic reasons, the angle of right ascension (or &quot;longitude&quot;) is measured in hours and minutes (24hr = 360 degrees)
Now the Black Widow pulsar is located at 19hr 57 minutes of right ascension and +20 degrees of declination (in the B1950 coordinates).  So its designation is PSR B1957+20.