Donatiello I, also known as Mirach's Goblin, is a dwarf spheroidal galaxy in the constellation Andromeda, located between 8.1 and 11.4 million light-years from Earth.

Follow-up observations with the Roque de los Muchachos Observatory led to a scientific paper on its discovery being published in December 2018.

[22][24] The discovery was corroborated using images from the Sloan Digital Sky Survey's ninth data release, which showed a faint object in the same area,[18][24] and was announced by Donatiello on 23 September 2016, via a post on Facebook.

[26][23] The team's scientific paper on the discovery and their follow-up observations was submitted to the journal Astronomy & Astrophysics in April 2018, and was accepted and published in December 2018,[27] with a preprint released on arXiv in October.

[25] Further detailed observations with the Hubble Space Telescope have been suggested by the paper's authors as a way to better determine the galaxy's distance from Earth and its relationship with NGC 404,[28] along with Donatiello I's size and mass.