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22-465: This concept was devised by American astronomers R. Edward Nather and Don E. Winget of the University of Texas at Austin . The consortium consists of individual astronomers interested in collaborating to study targets designated by a principal investigator. Where colleagues are not available, astronomers are dispatched to sites that allow telescope time to visitors. Initial funding for WET came from

44-599: A continuous sequence of data that can then be processed. After constructing a light curve , the data is subject to a Fourier transform to obtain the frequencies of pulsation . Referred to as an XCov, the typical observing run with the WET lasts from 10 to 14 days, and is scheduled for once or twice a year. The first observation run took place in March, 1988, and it included the Multiple Mirror Telescope in

66-438: A few weeks per year. Analysis of observed phenomena, along with making predictions as to the causes of what they observe, takes the majority of observational astronomers' time. Astronomers who serve as faculty spend much of their time teaching undergraduate and graduate classes. Most universities also have outreach programs, including public telescope time and sometimes planetariums , as a public service to encourage interest in

88-505: A grant by the US National Science Foundation , which lasted through 1998. For each site, an observing run begins when the sky is dark, and continues until stopped by weather or dawn. A photometer is used to observe the target object, a nearby comparison star, and the background sky. The data is then sent to the control center. Each site in turn takes up an overlapping observation run, so the result is, ideally,

110-421: A long period is vulnerable to weather conditions, the need to allocate time for each telescope, and the situation of each participating astronomer. It was recognized that satellites could accomplish the same task with fewer issues, but at a far higher cost. The MOST spacecraft , launched in 2003, was an early effort to pursue this application. It was able to monitor individual stars for periods of up to 30 days, but

132-605: A network of small telescopes around the world to capture small variations in the light output of a white dwarf caused by its seismic oscillations. One of Winget's projects involves studying white dwarfs using the Z machine pulsed-power electromagnetic wave generator at the Sandia National Lab in New Mexico . In 1983, Winget was awarded the Robert J. Trumpler Award for an outstanding doctoral dissertation by

154-426: A star of this class, fulfilling the prediction of his dissertation and marking the first time in which a class of variable stars was predicted to exist before any instances of it were observed. With Ed Nather , his colleague at University of Texas, Winget introduced the technique for studying the seismology and the inner structure of white dwarfs called " Whole Earth Telescope ". The technique involves coordinating

176-465: A university distinguished teaching professor at the University of Texas at Austin . Much of Winget's research concerns the study of white dwarf stars. Winget's doctoral research at the University of Rochester predicted the existence of DBV stars , a certain class of pulsating white dwarf . After becoming a faculty member at the University of Texas, he and his colleagues discovered GD 358 ,

198-720: The Astronomical Society of the Pacific . He received the 1987 Newton Lacy Pierce Prize in Astronomy from the American Astronomical Society . Astronomer An astronomer is a scientist in the field of astronomy who focuses on a specific question or field outside the scope of Earth . Astronomers observe astronomical objects , such as stars , planets , moons , comets and galaxies – in either observational (by analyzing

220-553: The DOV, DBV, and DAV types, Delta Scuti variables , a rapidly oscillating Ap star , and cataclysmic variables . A total of 16 XCov runs had been completed by May 1998, often covering more than one target per run. Only one failure was reported, for the roAp star HD 166473. Operations for WET moved to Iowa State University in 1995 when the International Institute for Theoretical and Applied Physics offered to help fund

242-545: The PhD level and beyond (as of 2024). Contrary to the classical image of an old astronomer peering through a telescope through the dark hours of the night, it is far more common to use a charge-coupled device (CCD) camera to record a long, deep exposure, allowing a more sensitive image to be created because the light is added over time. Before CCDs, photographic plates were a common method of observation. Modern astronomers spend relatively little time at telescopes, usually just

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264-673: The US, a 1.8 m aperture telescope at the South African Astronomical Observatory , and the IUE observatory in orbit around the Earth. The first target for the run was the star PG 1346+082, or CR Boötis , an AM CVn star . The second target was V803 Centauri , a cataclysmic binary . The campaign was able to monitor the star systems for a continual period of 15 days from six participating sites. The early focus of

286-660: The WET program. In 2004, the governing council of WET agreed to study private funding for its operations. This resulted in the formation of the Delaware Astroseismic Research Center (DARC) the following year, and WET operations were moved from Iowa to Delaware. The first run supported by DARC was XCONV25 during May 2006. Operations are supported by the Mount Cuba Astronomical Observatory and the University of Delaware . The ability to collect photometric data over

308-421: The core sciences, a competency examination, experience with teaching undergraduates and participating in outreach programs, work on research projects under the student's supervising professor, completion of a PhD thesis , and passing a final oral exam . Throughout the PhD training, a successful student is financially supported with a stipend . While there is a relatively low number of professional astronomers,

330-536: The data) or theoretical astronomy . Examples of topics or fields astronomers study include planetary science , solar astronomy , the origin or evolution of stars , or the formation of galaxies . A related but distinct subject is physical cosmology , which studies the Universe as a whole. Astronomers usually fall under either of two main types: observational and theoretical . Observational astronomers make direct observations of celestial objects and analyze

352-903: The data. In contrast, theoretical astronomers create and investigate models of things that cannot be observed. Because it takes millions to billions of years for a system of stars or a galaxy to complete a life cycle, astronomers must observe snapshots of different systems at unique points in their evolution to determine how they form, evolve, and die. They use this data to create models or simulations to theorize how different celestial objects work. Further subcategories under these two main branches of astronomy include planetary astronomy , astrobiology , stellar astronomy , astrometry , galactic astronomy , extragalactic astronomy , or physical cosmology . Astronomers can also specialize in certain specialties of observational astronomy, such as infrared astronomy , neutrino astronomy , x-ray astronomy , and gravitational-wave astronomy . Historically , astronomy

374-419: The field is popular among amateurs . Most cities have amateur astronomy clubs that meet on a regular basis and often host star parties . The Astronomical Society of the Pacific is the largest general astronomical society in the world, comprising both professional and amateur astronomers as well as educators from 70 different nations. As with any hobby , most people who practice amateur astronomy may devote

396-489: The field. Those who become astronomers usually have a broad background in physics, mathematics , sciences, and computing in high school. Taking courses that teach how to research, write, and present papers are part of the higher education of an astronomer, while most astronomers attain both a Master's degree and eventually a PhD degree in astronomy, physics or astrophysics . PhD training typically involves 5-6 years of study, including completion of upper-level courses in

418-694: The majority of their time working on research, although they quite often have other duties such as teaching, building instruments, or aiding in the operation of an observatory. The American Astronomical Society , which is the major organization of professional astronomers in North America , has approximately 8,200 members (as of 2024). This number includes scientists from other fields such as physics, geology , and engineering , whose research interests are closely related to astronomy. The International Astronomical Union comprises about 12,700 members from 92 countries who are involved in astronomical research at

440-513: The program was the study of pulsating white dwarfs . Most such stars exhibiting non-radial pulsations have multiple pulsation modes, with some having frequencies on the order of a cycle per day. The only way to observe these extended frequencies is continually over durations longer than 24 hours. The observations of PG 1159-035 with the WET, reported in 1991, initiated the study of white dwarf seismology, later termed asteroseismology . By 1998, WET runs had been performed on pulsating white dwarfs of

462-605: Was limited to a visual magnitude of 6 or brighter. The Kepler space telescope was launched in 2009 and was able to observe some stars continuously for up to four years. As of 2021, the TESS satellite is performing asteroseismology down to magnitude 17. Don Winget Don E. Winget is an American astronomer and astrophysicist who studies white dwarf stars. He is the Harlan J. Smith Centennial Professor in Astronomy and

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484-498: Was more concerned with the classification and description of phenomena in the sky, while astrophysics attempted to explain these phenomena and the differences between them using physical laws . Today, that distinction has mostly disappeared and the terms "astronomer" and "astrophysicist" are interchangeable. Professional astronomers are highly educated individuals who typically have a PhD in physics or astronomy and are employed by research institutions or universities. They spend

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