The National Solar Observatory or NSO is an astronomy organization that focuses on studying the Sun and whose main mission is to advance our knowledge about the Sun, both as an object of astronomy and as a very dominant external factor that influences the Earth. It aims to provide tools, resources, and forefront observational opportunities to communities and individuals who are researching about the Sun.

The organization operates cutting edge observational facilities. It continues to develop advanced instrumentation in studying the Sun both in-house and through outside partnerships, conducts solar research, as well as expands public and educational outreach regarding their studies and researches.

The National Solar Observatory currently runs two facilities. They are located in two different locations. One is located at Sacramento Peak in New Mexico while the other one is at Kitt Peak in Arizona. The facility in Sacramento Peak boasts of a telescope called the Dunn Solar Telescope that has a de-rotated 100 meter vacuum column.

The Association of Universities for Research in Astronomy operates the National Solar Observatory under an agreement which was entered into with the National Science Foundation. The Observatory is being operated for the benefit of the astronomical research community.

Researchers who wish to make use of the facilities of the NSO will have to apply first before they can conduct any kind of research there. Uses of the telescopes on the sites are also often fully booked. It is therefore best that researchers request telescope time in advance to make sure they get the access time they need.

The National Solar Observatory facilities are open for visitors during the day. Guided tours as well as private tours can be arranged depending on the current schedules on the facilities. Night time stargazing programs are also being offered at the Kitt Peak facility. Kitt Peak is located 56 miles southwest of Tucson, Arizona.