2002 MS₄ was discovered on 18 June 2002 by Chad Trujillo and Michael Brown at Palomar Observatory.
The discovery was announced by the Minor Planet Center on 21 November 2002.

In 2007, an archive search revealed the existence of several precovery observations of 2002 MS₄, the earliest of which was taken on 8 April 1954, as part of the Digitized Sky Survey at Palomar Mountain.

In July 2016, 2002 MS₄ was observed by the New Horizons spacecraft, as part of its extended Kuiper belt mission.
The observations significantly improved the knowledge of 2002 MS₄'s orbit and phase curve.

As of November 2019, 2002 MS₄ has been observed 74 times.
It has an observation arc of 64 years.
2002 MS₄ was discovered on 18 June 2002 by Chad Trujillo and Michael Brown at Palomar Observatory. The discovery was announced by the Minor Planet Center on 21 November 2002.
In 2007, an archive search revealed the existence of several precovery observations of 2002 MS₄, the earliest of which was taken on 8 April 1954, as part of the Digitized Sky Survey at Palomar Mountain.
In July 2016, 2002 MS₄ was observed by the New Horizons spacecraft, as part of its extended Kuiper belt mission. The observations significantly improved the knowledge of 2002 MS₄'s orbit and phase curve.
As of November 2019, 2002 MS₄ has been observed 74 times. It has an observation arc of 64 years.
(307261) 2002 MS4