History of HAO Slideshow

Seventy-Five Years of HAO History
The Climax, Colorado Observatory in 1940
Climax, Colorado Observatory

In 1940, Harvard graduate student Walter Orr Roberts and his doctoral adviser, astrophysicist Donald Menzel, founded a small solar observing station high on the Continental Divide in Climax, Colorado. Here, Walt Roberts installed the Western Hemisphere's first Lyot coronagraph, an instrument that uses a metal occulting disc to block off the face of the Sun, creating an artificial eclipse and rendering the corona visible.

Walt and Janet Roberts in Climax, ~1940
Walter and Janet Roberts

Walt and Janet Enjoying fresh snow around the Climax Observatory.

The Climax Observatory in the 1940s
The original Climax Observatory

Walter Orr Roberts

Walt Roberts' assignment at the Climax Observatory was to last only one year, but, with the country's sudden entry into the war, he remained at Climax as sole observer, making daily observations of the solar chromosphere and corona.

Solar spicules observed (top) and sketched (below), 1944
Observations and Sketch of Solar Spicules

Observations (top) and observer sketch (bottom) of solar spicules from the Climax Observatory.

Granddaddy Prominence observed in 1946
Granddaddy Prominence

Some filaments and prominences can reach impressive sizes, and remain visible very far above the solar disk. This prominence was photographed in June 1946 again through a filter centered on H-alpha, and extends some 200000 km above the solar surface; the Earth would easily fit under it. The bright arch at the bottom of the picture delineates the solar limb. Prominences extending so far up above the photosphere are usually not static, but are expanding outward in an eruptive phase.

Bernard Lyot visits Climax, 1946
Bernard Lyot visits Climax

Bernard Lyot (left), the inventor of the coronagraph, visits the HAO installation on Fremont Pass during July 1946. Earlier that year, the efforts were formally incorporated in "The High Altitude Observatory of Harvard College and the University of Colorado." HAO's first two employees were John (Jack) Wainwright Evans Jr. (center) and Walt Roberts (right).

HAO at CU, 1948
Climax Observatory becomes HAO

HAO's laboratories were relocated to the CU campus in 1948. HAO's laboratories were relocated to the CU campus. In the mid-50's HAO and CU cooperated to establish the Summers-Bausch Observatory (seen on left side of photo). During the last half of the 1950s, HAO scientists pooled their talents with CU's faculty to form the University's Department of Astro-Geophysics. The Astro-Geophysics building (seen on right side of the photo) was dedicated October 8, 1960.

New site for observatory at Chalk Mountain, 1949
Construction begins at Chalk Mountain

The new site at Chalk mountain was found and prepared beginning in 1949. In 1952, the observatory facilities were moved 5 miles to the west from the original site to avoid the impact of airborne particulate matter produced by the neighboring mining operations at Climax Molybdenum Company.

Jack Evans measuring quartz crytals, 1950
Jack Evans

Jack Evans makes preliminary measurements on two large quartz crystals in order to construct a quartz monochromator. Quartz slabs cut from these crystals were layered and spaced to create a "birefringent filter". Bernard Lyot had pointed out how such a filter could operate, but it was Evans who perfected the construction process. The birefringent filters are capable of transmitting very narrow wavelength (~5 angstroms at a time in any part of the spectrum) bands of electromagnetic radiation.

Chalk Mountain prominence, 1951
Early image from Chalk Mountain observatory

An early H-alpha image showing a prominence

Frederick B. Pearson, chief optician for the observatory, and Dr. John W. Evans grind a coronagraph lens, 1951
Grinding Coronagraph Lens

The delicate job of grinding a 16 inch lens for an "inside-out" telescope or coronagraph is under way in the Boulder optical shop of HAO. Pictured adjusting the grinding mechanism are Frederick B. Pearson (left) chief optician for the observatory, and Dr. John W. Evans, noted optical physicist and member of the observatory staff. Two 26 foot coronagraphs, the world's largest, were then under construction by the Westinghouse Electric Corporation at Sunnyvale, California. The instruments were used for solar research programs conducted by HAO, which at that time was affiliated with Harvard University, Harvard College Observatory, and the University of Colorado.

1952 Khartoum Eclipse Expedition
Khartoum Eclipse Expedition

In collaboration with the Naval Research Laboratory, HAO observed the 25 February 1952 eclipse in Khartoum, Sudan with a spectrograph. A large number of spectrograms were obtained by the eclipse team of Jack Evans, Robert Cooper, and Robert Lee.

The Khartoum coronagraph is deployed, 1952
Khartoum Eclipse Expedition

This remarkable eclipse experiment -- the most advanced of its kind at that time -- studied the spectrum of elements present in the solar chromosphere with unprecedented height discrimination and high spectral resolution. The spectra provided the first experimental evidence for the newly developed concept of non-local thermodynamic equilibrium conditions in the solar atmosphere. Results from the experiment formed the basis for numerous publications at HAO and elsewhere in the 1953 - 1960 period and, in fact, provided the impetus for HAO to develop into a broad, research-oriented institution.

Chalk Mountain dome in 1954
Observatory at Chalk Mountain

The new dome at Chalk Mountain was completed in 1954. The larger dome housed a 16 inch coronagraph and its associated spectrograph and magnetograph. The smaller dome contained the older 5 inch coronagraph and the H-alpha flare patrol telescope which operated constantly during clear daylight hours.

Climax Observatory houses first k-coronameter, 1956
Climax Observatory is Home To First K-coronameter

In 1956, HAO built the world’s first K-coronameter (the Mk1) and deployed it to Climax. The K-coronameter was designed to view polarized light from the Sun that is scattered in the outer solar atmosphere known as the corona. Light is polarized when many of the light waves vibrate in a preferred direction (determined by the magnetic field) instead of vibrating in random directions. Detection of this polarized, scattered light allowed HAO scientists to measure the brightness of the corona out to greater heights. Climax observations of the corona revealed that the brightness of the corona changed over the 11-year sunspot cycle, with the brightest parts being located over regions where the magnetic field was strongest: sunspots and active regions. HAO scientist, Gordon Newkirk, produced a sophisticated model of coronal density and magnetic field in 1958, based on the interpretation of coronal data from Climax. It remained a standard reference model for many decades. The Climax observatory continued to acquire important observations of the Sun and remained HAO’s primary observing site until it closed in 1972.

Sydney Chapman
Sydney Chapman

Sydney Chapman, distinguished author of hundreds of research works on the upper atmosphere, earth magnetism, the aurora, and the solar corona, had a great influence on the course of HAO's research. Beginning in 1957, Chapman returned to HAO each summer as a visiting scientist. He spent his winters at the University of Alaska's Geophysical Institute at Fairbanks. He also served as international president of the International Geophysical Year.

Eclipse expedition to Pukapuka, Northern Cook Islands, 1958
Eclipse Expedition to The Northern Cook Islands

HAO took its equipment to Pukapuka in the North Cook Islands to observe an eclipse.

Gordon Newkirk Jr. Coronascope-I Balloon Experiment, 1960
Gordon Newkirk, Jr. Coronascope-I Balloon Experiment

Extended observation of the intermediate corona was the ultimate purpose of balloon experiments such as the one pictured. This project used an unmanned stratospheric balloon to raise a coronagraph above the dust and smoke of the lower atmosphere for several hours of continuous operation. At the end of the day's observation, the instrument and its photographs were returned to the ground by parachute. The gondola holding the instrumentation was the same one used by Princeton physicist Martin Schwarzschild to take images of the solar granulation with his "stratoscope" in 1959. The first two successful deployments of Coronascope-I were made outside of Minneapolis, in cooperation with the General Mills Company, in September and October of 1960. An improved version of the instrument, The Coronascope II, was launched at the National Scientific Balloon Facility in Palestine, Texas in March of 1964 and produced the first images of the outer corona without a solar eclipse. The Coronascope II instrument flew in two other flights in 1965 and served as a test-bed for the development of the HAO Skylab coronagraph that was launched into space in 1973.

Construction of the NCAR Mesa Lab in Boulder, 1965
Construction of the NCAR Mesa Lab

In 1960, NCAR began construction operations in Boulder, Colorado. The building was designed by the architect I. M. Pei who decided not to compete with the scale of the Rockies but to make a building that was without conventional scale. Pei designed NCAR to impinge minimally on the vegetation and topography of Boulder’s Mesa by returning to elemental forms of sheer walls and unfinished concrete the color of the mountains. The National Center for Atmospheric Research (NCAR) was dedicated in Boulder Colorado on May 10, 1967.

Mauna Loa Solar Observatory, 1965
Construction of the Mauna Loa Solar Observatory

HAO established the Mauna Loa Solar Observatory in 1965, and over time instruments from the Climax site were moved here to take advantage of the superior seeing conditions.

 Interior view of MLSO's dome showing the tracking spar
Mauna Loa Solar Observatory Spar

An interior view of MLSO's dome showing the tracking spar holding the Mk1 instrument.

Jack Eddy, John Firor, and Bob Lee prepare the eclipse expedition coronagraph for 1966 eclipse expedition to Bolivia
Eclipse Expedition to Pulacayo, Bolivia

Jack Eddy, John Firor, and Bob Lee prepare the eclipse expedition coronagraph at the HAO Astro-Geophysics Department building on the University of Colorado campus. Two different HAO teams were involved in this eclipse. A coronal camera designed by Gordon Newkirk Jr. made its debut with photometric and polarimetric observations from a site near Pulacayo, Bolivia.

HAO image of 1966 eclipse in Bolivia
Eclipse Expedition to Pulacayo, Bolivia

This eclipse photograph was the first to be made with the Newkirk camera that contained a special filter to offset the rapid change in brightness of the solar corona with height. It allowed scientists to record the solar corona for the first time out to nearly 2 million miles (4 ½ times the radius of the Sun) using a single exposure setting. The two teams acquired data that yielded information needed to construct the densities and temperatures in the various bright white structures, known as streamers, visible in the eclipse image. The team was surprised when the results showed that the properties of the different streamers sometimes varied significantly from one streamer to the next. It pointed to the need for more detailed observations throughout the solar atmosphere to understand these variations. The Newkirk coronal camera continued to produce some of the most spectacular and useful pictures ever taken of the white-light corona at eclipses for the next 30 years (see the HAO Eclipse page).

Near-infrared iron line observations were conducted with a new instrument carried by a NASA aircraft based at Porto Alegre, Brazil.
Eclipse Expedition to Pulacayo, Bolivia

While the coronagraph was deployed on the ground, near-infrared iron line observations were conducted with a new instrument carried by a NASA aircraft based at Porto Alegre, Brazil.

Roger Kopp and Jack Gosling working on an instrument for the 7 March, 1970 eclipse in San Carlos Yautepec, Mexico.
Constructing an Instrument for the 1970 Eclipse Expedition

Roger Kopp and Jack Gosling working on an instrument for the 7 March, 1970 eclipse in San Carlos Yautepec, Mexico.

HAO Scientists using NCAR Vacuum Tunnel Facility, 1971
HAO Scientists using NCAR Vacuum Tunnel Facility

HAO staff working with ATM Instrument in NCAR Vacuum Tunnel Facility, NVTF (in picture: Ross, Hanson, Newkirk, and Lacey)

Skylab launched in 1973 with HAO coronagraph

Skylab was the United States' first space station (the first ever space station was the Soviet Salyut 1). Skylab was a 77-ton outpost launched on May 14, 1973 on a modified Saturn V rocket from Kennedy Space Center (formally Cape Canaveral). It remained in Earth orbit from 1973 to 1979 and was visited by crews three times between 1973 and 1974. They reached the station by a Command/Service Module (CSM) launched atop the smaller Saturn IB. Skylab program objectives were twofold: To prove that humans could live and work in space for extended periods, and to expand our knowledge of solar astronomy well beyond Earth-based observations. Nearly 300 scientific and technical experiments were performed including medical experiments on humans' adaptability to zero gravity, solar observations, and detailed Earth resources experiments. The astronauts recorded 127,000 frames of film of the Sun, confirming the existence of coronal holes on the Sun, which are sources of the solar wind.

An image from HAO's coronagraph aboard Skylab showing a coronal mass ejection.
HAO's Skylab Coronagraph

Skylab astronauts operated a coronagraph designed by and built for the NCAR High Altitude Observatory (HAO). The HAO coronagraph recorded 115 explosive solar events known as coronal mass ejections (CMEs), as shown in the above image. CMEs are the sudden expulsion of magnetized plasma from the Sun’s atmosphere that are ejected into the solar wind with an average speed of 1 million mph. The fastest CMEs have been recorded traveling near the Sun at 9 million mph. The Sun can produce up to 4 or 5 CMEs per day during solar maximum activity and as few as a couple per week during solar minimum activity. The HAO Skylab observations established important clues about the relationship of CMEs to other forms of solar activity, such as erupting prominences and flares and they provided the best set of observations on CME basic properties for their time.

False-color corona by HAO's coronagraph aboard Skylab
False-color image of corona

This false-color image of the solar corona was made with the white-light coronagraph aboard the Skylab spacecraft, with the moon (upper left) approaching the sun to create the total eclipse of 30 June 1973. Here, the light from the solar disk is blocked by an occulting disk, which appears as the solid black circle in the center of the field. The black gap at the bottom is the shadow of a pylon, which holds the occulting disk in place. The colors were added to the image by computer processing after the data were analyzed.

Delivery of the new CRAY-1 to NCAR in 1977
CRAY-1 comes to NCAR

NCAR accepts the first production model of the CRAY-1 supercomputer. The five-ton machine is lowered through the ceiling of a newly built underground computing center. Subsequent machines from Cray Research dominated NCAR computing into the 1990s.

Rocket-borne HAO coronagraph, 1979
Rocket-borne Coronagraph

In the late 1970s, HAO/NCAR joined forces with the Smithsonian Astrophysical Observatory to launch two coronagraphs on a Black-Brant V rocket (left). The coronagraphs were designed to observe the outer atmosphere of the Sun known as the corona in order to determine its temperature and the density, and to detect outflows of coronal material. This information was needed to understand how the corona is heated to over a million degrees and how regions of the corona are accelerated with enough energy to escape into interplanetary space to form the solar wind. The first coronagraph was an HAO/NCAR instrument used to determine the brightness and of the corona (right). Bright areas of the corona occur where the atmosphere is held down by gravity and the Sun’s magnetic field. Dark areas are regions where the atmosphere escapes the Sun and flows outward to form the solar wind.

Mk3 Coronameter installed at MLSO, 1979
The Mk3 Coronameter Installed at MLSO

In 1957, HAO built the world’s first K-coronameter and deployed it to their observatory at Climax, Colorado. It was able to measure the brightness of the corona at several heights. A major advancement was made in 1979 when a new state-of-the-art K-coronameter, the Mk3, was installed in HAO’s Mauna Loa Solar Observatory. The Mk3 was the first ground-based instrument to produce artificial eclipse images of the corona in white light, acquiring images every 3 minutes during each observing day. It was the only instrument able to routinely record white light images of the very low corona. This was a major breakthrough, providing daily information on the variation of the structure and brightness of the Sun’s corona. The Mk3 recorded hundreds of explosive events known as coronal mass ejections (CMEs), providing information on the formation, acceleration and sources of these events. Mk3 measurements demonstrated that the brightness of the corona varies by nearly a factor of 6 over the 11-year sunspot cycle, attaining its brightest levels at activity.

K Emission Line Polarimeter composite with Mk3 image, 1980
The K Emission Line Polarimeter (KELP)

The K Emission Line Polarimeter (KELP) was built in 1974 by the High Altitude Observatory (HAO) / NCAR in collaboration with the Sacramento Peak Observatory. KELP was designed to measure polarized light from the Sun’s atmosphere. Light is said to be polarized when many different waves of light vibrate along the same direction, instead of in all different directions. In the Sun’s corona, the magnetic field provides the preferred direction to polarize light. By measuring the polarization you can learn about the magnetic field, which is important because the field organizes the structure of the corona and the field can release energy that creates solar activity. KELP made successful observations of the direction of the coronal magnetic field that helped to prove the power of the technique of using polarization. KELP observations became even more informative in 1980 when they were combined with new daily images of the solar corona from the Mauna Loa Mk3 K-coronameter (as shown in the blue/white photo). Scientists could relate the direction of the magnetic field provided by KELP, to the structures of the corona shown in Mk3 images. These data gave scientists a better understanding of the shape of the coronal magnetic field and helped to determine the sources of the solar wind, the continuous stream of particles that escape the Sun and travel throughout the solar system.

The Solar Maximum Mission satellite repair mission, 1984
The Solar Maximum Mission

The Solar Maximum Mission (SMM) was launched on 14 February 1980 to study the Sun during the most active part of the Sun’s activity cycle. It carried a variety of instruments to study solar activity such as flares and explosive events known as Coronal Mass Ejections (CMEs) and to measure the Sun’s total irradiance (power emitted by sunlight at all wavelengths) for climate studies. SMM malfunctioned one year after launch. In April 1984 it became the first satellite to be repaired in orbit by astronauts aboard the Space Shuttle (pictured). The repair provided five more years of valuable observations. Increases in solar activity acted to swell the Earth’s atmosphere and increase satellite drag. As a result of the increase in activity in 1988 and 1989, the orbital height of SMM decreased and it burned up in the Earth’s atmosphere on December 2, 1989.

HAO's coronagraph aboard the SMM satellite records a CME and Halley's Comet
The Solar Maximum Mission Coronagraph

HAO/NCAR designed and operated the coronagraph onboard SMM. The coronagraph recorded over 1,300 CME events (such as the one in the above image, top-center) that helped scientists to better understand how these events form by measuring their basic properties and how they relate to other types of solar activity such as flares. The HAO coronagraph was also used to discover ten sungrazing comets belonging to the Kreutz sungrazer group, which formed when a comet broke up several centuries ago. In 1986, the HAO SMM coronagraph pointed towards Halley’s comet as it made its closest approach to the Sun, revealing new information about the conditions in the comet’s head and tail are effected by the solar wind, a steady stream of particles escaping from the Sun (above, lower-right).

Fourier Tachometer data, 1980s
The Fourier Tachometer

Scientists have long been aware of oscillations in the photosphere (sun's surface). These oscillations can be measured in wavelengths of light (Doppler shifts). A Fourier tachometer was developed in the 1980s by Timothy Brown of the High Altitude Observatory in order to measure these Doppler shifts. The bands in this image denote changes in velocity, or oscillations, produced by the sun's rotation. Data from the oscillating Doppler shifts provide clues to the sun's temperature, composition, rotation, flows, and magnetic field strength.

The Redwood Telescope for measuring atmospheric scintillation
The Redwood Telescope

Tim Brown is shown with what was called the Redwood Telescope. Its aim was to measure atmospheric scintillation noise in stellar photometry, using the multiple panes of glass as mirrors to feed light from a star to a single 8-inch telescope. Since each pane sees the star through a different volume of atmosphere, the scintillation noise for the sum should be smaller than for the same-size telescope looking directly at the star. The redwood part was designed and built by Lee Lacey.

The Earth's Aurora Australius
NCAR's Upper Atmosphere Group Joins HAO

HAO's connections to upper-atmosphere and magnetosphere science expanded as the upper atmosphere group from NCAR's Atmospheric Chemistry and Aeronomy Division transferred in.

Advanced Stokes Polarimeter data, 1991
The Advanced Stokes Polarimeter

Spectropolarimetry provides the most complete and detailed measurement and analysis of light, its interaction with matter and information about the state of magnetic fields. It is the study of polarized light in a narrow range of wavelengths that are produced by known states of atoms. One of the most successful HAO spectropolarimeters was the Advanced Stokes Polarimeter (ASP). By all accounts, this instrument ushered in a new era of quantitative, high-resolution vector magnetic field observations. Operated at Sacramento Peak Observatory, it inferred the three-dimensional magnetic structure of sunspots and other magnetic features.

Spartan 201's instruments included an HAO coronagraph, 1993
The Spartan Spacecraft

The Spartan spacecraft were a series of experiments carried by the Space Shuttle. The program was based on the idea of a simple, low-cost platform deployed from a space shuttle in orbit for a 2-3 day flight, then recovered and returned to Earth. Spartan 201 carried a coronagraph designed by HAO/NCAR. It was launched and retrieved by Space Shuttle astronauts five times between April 1993 and October 1998, and studied the Sun's extremely hot corona and the solar wind. The coronagraph was used to determine the density of the corona and to study explosive events in the Sun’s atmosphere known as Coronal Mass Ejections (CMEs). The Spartan 201 spacecraft now resides at the National Air and Space Museum.

Model merger
HAO/NCAR Model Blend

A landmark union joins two key NCAR models, the Thermosphere/Ionosphere/Mesosphere-Electrodynamics General Circulation Model (TIME-GCM) and version 2 of the Community Climate Model (CCM2). The union evolved by 2000 into the Whole Atmosphere CCM (WACCM), that can simulate the Earth's atmosphere from top to bottom.

The STARE telescope with simulated transit image, 1999
The STARE Exoplanet Telescope

The STellar Astrophysics and Research on Exoplanets (STARE) telescope consisted of a small 10 cm (~ 4 inch) aperture designed to search for planets around other stars (known as exoplanets) and to study the stars themselves. The instrument was housed in a small dome on Tenerife in the Canary Islands, Spain. It was designed, built and operated by HAO/NCAR in conjunction with the Astrophysical Institute of the Canaries (IAC). STARE used a method of finding planets that relies on the edge-on alignment of the extrasolar system. If a planetary system is oriented so that Earth lies near the plane of the planet's orbit, then once per orbit the planet passes between its star and the Earth (simulated in the above image), causing a transit. During a transit, the planet blocks some of the light from the star, causing the star to appear dimmer. This orientation method favors finding larger planets orbiting close to their parent star. STARE has successfully detected large planets around other stars. The observations were used to determine the planets sizes, masses and density, which provided the information needed to determine if the planet was a gas giant like Jupiter, or a rocky planet like Earth.

HAO 60th anniversary cake
HAO's 60th Anniversary

HAO celebrated its 60th anniversary in style, with Walt Roberts-themed cake and cookies.

The TIMED spacecraft, 2001
The TIMED spacecraft

The TIMED (Thermosphere Ionosphere Mesosphere Energetics and Dynamics) spacecraft was launched in 2001 by NASA to study the influence of the Sun and humans on the least explored region of Earth’s atmosphere – the mesosphere and lower thermosphere (MLT). The MLT region between 50 and 200 km is a gateway between Earth’s environment and space. The TIMED mission helps scientists to understand how solar variability and lower atmospheric processes combine together to make the MLT region the most dynamic and variable part of Earth’s upper atmosphere.

The TIMED spacecraft carries four instruments: a Global Ultraviolet Imager (GUVI), and infrared limb-sounder (SABER), a solar ultraviolet spectrometer (SEE), and a Fabry-Perot interferometer (TIDI). The TIDI instrument measures the neutral winds in the MLT region by monitoring the Doppler shift in the airglow. The TIDI data are being used for studying tides and planetary waves in the MLT region. HAO/NCAR is primarily responsible for the TIDI project, in collaboration with the Space Physics Research Laboratory at the University of Michigan and Northwest Research Associates.

2005 numerical simulations of Sun
Numerical simulations of Sun

(clockwise, from top-left)

The image is a Molleweide projection located just below the solar surface, with yellow/white tones representing warmer plasma and blue/black tones representing cooler plasma. The solar equator is a few Kelvin warmer than the poles in this simulation, while localized spots of cool plasma dot the layer, corresponding to swirling downflow plumes.

Here we see the radial velocity field just below the solar surface in one such simulation, shown in a Molleweide projection. Bright and dark tones denote upflowing and downflowing plasma respectively. An intricate network of strong, narrow downflow lanes blankets the entire surface, often forming localized, swirling plumes.

This ghostly image shows the enstrophy, which is the magnitude of the vorticity vector squared, in a numerical simulation of solar convection. A Molleweide projection is shown near the middle of the convection zone, about 100 Mm below the solar surface. The enstrophy is very intermittent, confined to very strong downflow plumes and lanes which produce vortex rings and sheets through the entrainment of surrounding plasma.

BC Low, 2005
BC Lowe giving a talk

HAO scientist Boon Chye (known as BC) Low gives a talk in front of a white board full of equations. Dr. Low was a senior scientist at NCAR (retired). He studied the solar atmosphere, with particular interest in the theory of basic physical processes and the solar corona as an integral natural system. He is also interested in applied and computational mathematics and collaborates with colleagues in the Institute of Mathematics for Geosciences.

Sunrise Gondola at launch, 2009
Sunrise Science Flight

Sunrise is a unique research project designed to capture features on the solar surface as small as 30 kilometers across (about 19 miles), more than double the resolution achieved by any other instrument to date. Carrying the largest solar telescope ever to have left Earth, Sunrise was launched on a gigantic helium balloon larger than a Boeing 747 jumbo jet, from the ESRANGE Space Centre in Kiruna, northern Sweden on June 8, 2009. The total equipment weighed in at more than six tons and reached a cruising altitude of 37 kilometers (23 miles) above the Earth's surface. The observations (an example is show as an inset above) are helping unlock important mysteries about the structure of the Sun's magnetic field and how it creates solar activity that can cause electromagnetic storms in the Earth’s upper atmosphere. It is also designed to study ultraviolet light from the Sun. Ultraviolet light has shorter wavelengths than our eyes can see. The amount of ultraviolet light produced by the Sun varies over the sunspot activity cycle which has implications for climate on Earth. Ultraviolet light does not reach the surface of the Earth but is absorbed in the ozone layer, where it deposits heat. Sunrise was carried high enough up to detect ultraviolet light carrying out the first ever study of small-scale bright magnetic structures on the solar surface in an important range of ultraviolet light. Sunrise is an international collaboration involving NCAR, NASA, Germany, Spain, Sweden, Lockheed Martin Corporation and the University of Chicago.

Sunrise Gondola recovery
Sunrise Gondola recovery

The Sunrise gondola and telescope landed on Somerset Island, an unpopulated island not too far away from Resolute Bay, a small air base. From there, the recovery operation was started and gondola, telescope, instruments and the data disks were successfully recovered.

Fabry-Perot Interferometer at Palmer Station, Antarctica, 2010
Palmer Station Fabry-Perot Interferometer

In 2010, an HAO-built Fabry-Perot interferometer was installed in Palmer Station, Antarctica (64S, 64W), with funding from the American Recovery and Reinvestment Act of 2009. The instrument measures upper-atmospheric winds by observing the Doppler shift of nightglow emissions. The wind measurements help scientists understand the cause of unusual patterns of the ionosphere like the Weddell Sea Anomaly, where the ionospheric density is greater at night than at day during the summer. The instrument filled a critical data gap.

HiWind launch

HiWind, led by PI Qian Wu, is the first balloon-borne Fabry-Perot interferometer specialled conceived to measure the daytime thermospheric winds by monitoring the neutral wind induced Doppler shift in the airglow emission O 630 nm.

Shown above is the launch from Kiruna, Sweden.

EMP at 2012 Australian eclipse
Eclipse Megamovie Project in Australia

The Eclipse Megamovie Project brings people together to share their solar eclipse images and experiences. The project invites the public, via common technologies, to share their total solar eclipse images at the project website (eclipsemegamovie.org/). Using the many contributed images, ultra-high time resolution movies of total solar eclipses will be created. These movies will open the door to learning about the Sun's corona, solar physics, and orbits of the Earth and Moon around the Sun. The November, 2012 eclipse in northern Australia was the first event, designed to test the concept. "The early morning sky was cloudy to the point where we missed 'first contact', the time at which the Moon starts to block out the Sun," said HAO's Scott McIntosh, who is heading up the Eclipse Megamovie Project with colleagues at NCAR and the University of California, Berkeley. This scientific cliffhanger had a happy ending: the clouds parted just before totality, allowing people on hand to witness the Sun fully obscured by the Moon above the Coral Sea for about two minutes.

The Australian was the first of several solar eclipse opportunities, culminating in August of 2017 when tens of millions of Americans—from Oregon on the west coast to South Carolina on the east—will have an outstanding opportunity to view a total solar eclipse. This extensive land-based total eclipse event will provide the opportunity to assemble a very large number of images—obtained by observers all along the path—into a continuous record of chromospheric and coronal evolution lasting an hour and a half!