McDonald Observatory was originally endowed by the Texas banker William Johnson McDonald (1844–1926), who left about $1 million — the bulk of his fortune — to The University of Texas at Austin to endow an astronomical observatory.

The provision of the will was challenged by McDonald's relatives, but after a long legal fight, the university received about $800,000 from the estate and construction began at Mt.

[3] Research today at the McDonald Observatory encompasses a wide variety of topics and projects, including the search for and understanding of planetary systems, stars and stellar spectroscopy, the interstellar medium, extragalactic astronomy, and theoretical astronomy.

It works closely with the astronomy department of The University of Texas at Austin while maintaining administrative autonomy.

[citation needed] The high and dry peaks of the Davis Mountains make for some of the darkest and clearest night skies in the region and provide excellent conditions for astronomical research.

Additionally, The University of Texas at Austin is a founding partner of the international collaboration to build the Giant Magellan Telescope.

[18][19] The two peaks also host a number of other instruments: The observatory experiences a semi-arid climate (Köppen BSk) with cool, dry winters and hot, wetter summers.

The Visitors Center conducts daily live solar viewings in a large theater and tours of the observatory's largest telescopes.