Conversation

Dwarf Planet candidate ED138 was not discovered until now because it currently lies in a region of the sky close to the plane of the Milky Way — a region filled with millions of stars.

The video below shows the orbital path of ED138, as observed by the NSF–DOE Vera C. Rubin Observatory from 4 March 2026 to 11 July 2026, against a background filled with stars.

The angular distance traveled in the 4 months is quite small, ~1°, given its orbital period of 281 years.

https://www.youtube.com/watch?v=_ssnabPxqxk
7/n

Here is the approx. location of dwarf planet candidate 2026 ED138 as seen in the evening sky from Cerro Pachón, Chile, home to the Vera C. Rubin Observatory.

It is quite close to the plane of the Milky Way, which is teeming with stars.

https://stellarium-web.org/

For more detailed co-ordinates, see https://www.minorplanetcenter.net/db_search/show_object?object_id=2026+ED138
8/n