Robert E. Holmes Jr. (b. 1956^[1]) is an American amateur astronomer and professional photographer.

In 2002 Holmes founded Astronomical Research Institute (ARI), a non-profit organization offering students observation time from telescopes installed at the Astronomical Research Observatory originally in Charleston, Illinois and later at Westfield, Illinois.

The Minor Planet Center credits him with the discovery of thirteen asteroids made between 2004 and 2010, partly in collaboration with Harlan Devore and Tomáš Vorobjov. In 2008, with 24-inch (0.61 m) and 32-inch (0.81 m) robotic telescopes at his Charleston observatory that he built himself, Holmes reported 11,593 observations of asteroids and near-earth objects to the Minor Planet Center, more than any other professional or amateur observatory.^[2]

Holmes discovered comet C/2008 N1 (Holmes).^[3][4]

The asteroid 5477 Holmes is named for him.^[1]

• List of minor planet discoverers

• Billy Hurley (October 11, 2018), "How Robert Holmes Finds Near-Earth Asteroids from His Home-Built Observatories", Tech Briefs, SAE Media Group (SAE International)
• NASA Planetary Defense: Backyard Asteroid Observer, Jet Propulsion Laboratory, June 30, 2017, Backyard astronomer Robert Holmes of Westfield, Illinois, is part of NASA's army of observers scanning the night sky for asteroids.
• Tony Reid (May 18, 2009). "There's no escaping his scope: Charleston man tracks dangerous asteroids for NASA". Herald & Review. Decatur, Illinois. CHARLESTON - Sleep tight: Robert E. Holmes Jr. is keeping watch.(subscription required)

• Astronomical Research Institute
• Robert Holmes: Shoemaker NEO Grant recipient profile, The Planetary Society