The High Altitude Observatory (HAO) is a laboratory of the US National Center for Atmospheric Research (NCAR). HAO operates the Mauna Loa Solar Observatory on Hawaii and a research institute in Boulder, Colorado.
Its staff conduct research and provide support and facilities for the solar-terrestrial physics research community. Topics covered include solar physics, the heliosphere, and the effects of space weather on Earth's magnetosphere, ionosphere, and upper atmosphere.[1]
HAO was originally founded in 1940 as a branch of the Harvard College Observatory, was transferred to the University of Colorado in the late 1940s, before becoming part of NCAR when the latter was founded in 1960.
HAO's mission is to understand the behavior of the Sun and its impact on the Earth, to support, enhance, and extend the capabilities of the university community and the broader scientific community, nationally and internationally, and to foster the transfer of knowledge and technology. As articulated in its Strategic Plan for 2011–2015, HAO's vision is to: Perform world-leading science to understand fundamentally and with predictive capability the sources and nature of solar and geospace variability; Provide scientific leadership and facilities to serve the wider community in common pursuit of these science objectives, and both support and benefit from the NCAR community; Support the education and training of early-career researchers in solar-terrestrial physics and instrumentation; and Provide advocacy for solar-terrestrial physics, promoting its results, and articulating its societal importance, to the rest of NCAR, the NSF, the university community, and the public.
HAO's telescopes are located at its Mauna Loa Solar Observatory, near the summit of that volcano on the big island of Hawaii. NCAR's solar observatory shares space on the campus of NOAA's larger Mauna Loa Observatory. HAO's researchers are based at NCAR headquarters, in Boulder, Colorado.
1952 - Khartoum, Sudan This was a joint HAO – Naval Research Laboratory expedition, which obtained 50 spectra of the eclipse features of the sun.
1958 – Pukapuka, Cook Islands in the PacificThis was a joint HAO – Sacramento Peak expedition that was unable to obtain a single photo due to rainstorms.
1959 – Fuertaventura, Canary Islands of SpainA joint HAO – Sacramento Peak expedition
1962 – Lae, New Guinea
1963 – Alaska and Canada
1965 – Bellingshausen Island, South Pacific
1966 – Pulacayo, Bolivia[2]
1970 - San Carlos Youtepec, Mexico[3]
1972 – Cap Chat, Canada
1973 – Loiengalani, Kenya[4]
1980 – Palem, IndiaHAO in collaboration with Southwestern at Memphis College, Tennessee
1981 – Tarma, Siberia, USSRHAO in collaboration with the Astronomical Council of the Academy of Sciences of the USSR, Moscow
1983 – Tanjung Kodok, Indonesia
1988 - Mindanao, PhilippinesIn Provocation No. 214, Dr. Roberts discusses the High Altitude Observatory (HAO) expedition to the Philippines to observe the eclipse of March 18. HAO expedition staff included Dick Fisher, Kristy Rock, Mike McGrath, and Lee Lacey.[5]
1991 - Mauna Loa, HawaiiHAO in collaboration with Rhodes College, Tennessee
1994 - Putre, Chile
1998 – Curaçao, Dutch Antilles[6]
2012 – Palm Cove, Queensland, Australia[7]
2017 - Preparing for the 2017 Eclipse[8]
Walter Orr Roberts was a graduate student under Donald Menzel at Harvard, and helped him set up a solar telescope at the Oak Ridge Station of Harvard College Observatory. In 1939, Menzel located a site for a western station in the Colorado mountains. In his unpublished memoirs, Menzel writes: “I returned the following summer, supervised the building of the observatory and an observer’s residence [on the mining property of Climax Molybdenum Company at Climax, Colorado], and started the installation of the equipment.[9]
“This branch of the Harvard College Observatory informally opened on 8 September 1940 at Climax Colorado (elevation 11,520 ft.). Its sole purpose was to study the sun, using the first coronagraph in the western hemisphere.” [10]
Walter Roberts and his wife arrived in the summer of 1940, and remained at the observatory for 7 years (throughout WWII and beyond). Menzel continues: “In the summer of 1940, however, Walter and I quickly solved the problems of our coronagraph. After I left, he soon had it working properly. He obtained daily records of the spectrum of the corona, which furnished us with a valuable index of solar activity.
At Climax, Walter Roberts quickly proved observationally what most astronomers had previously suspected, that the corona itself rotated with the same period as the solar surface, in something over twenty-five days. He initiated a study of the fine structure of the solar atmosphere, determining the behavior of what he called “spicules,” a phenomenon that I had myself briefly discussed while at Lick Observatory. These studies formed the basis for his doctorate thesis submitted for the degree a year or two later.” [11]
Work at the observatory was classified during WWII because of its value in predicting radio disturbances from the study of the corona. "The wartime work of the observatory was done under the auspices of the Navy, although overall direction remained in the hands of Harvard.” Post WWII, The National Bureau of Standards contracted the observatory for reports on solar activity. In 1946, CU Boulder became a joint sponsor with Harvard of the observatory, while the Central Radio Propagation Laboratory (CRPL) of the NSB funded HAO's operational costs. The headquarters of HAO was moved to Boulder in 1947.[12]
The founding director of the High Altitude Observatory was Walter Orr Roberts. The current director is Scott McIntosh. A list of all HAO directors since the founding of the observatory is given below.
| HAO Director | Dates in office | |
|---|---|---|
| 1940 - 1960 | ||
| 1961 - 1968 | ||
| 1968 - 1979 | ||
| 1980 - 1986 | ||
| Peter A. Gilman | 1987 - 1989 | |
| Thomas E. Holtzer | 1990 - 1995 | |
| Michael T. F. Knölker | 1995 - 2009 | |
| Michael J. Thompson | 2010 - 2014 | |
| Scott W. McIntosh | 2014 - |