Leuschner Observatory
Encyclopedia
Leuschner Observatory, originally called the Students' Observatory, is an observatory operated by the University of California, Berkeley
. The observatory was built in 1886 on the Berkeley campus. For many years, it was directed by Armin Otto Leuschner
, for whom the observatory was renamed in 1951. In 1965, it was relocated to its present home in Lafayette, California
, approximately 10 miles (16.1 km) east of the Berkeley campus.
Presently, Leuschner Observatory has two operating telescopes. One is a 30 inches (762 mm) optical telescope
, equipped with a CCD for observations in visible light and an infrared
detector used for infrared astronomy
. The other is a 4-meter radio
dish used for an undergraduate radio astronomy
course. The observatory has been used to perform professional astronomy
research, such as orbit
determination of small solar system bodies in the early 1900s, and supernova
surveys in the 1980s and 1990s. It has also served as a primary tool in the education of graduate
and undergraduate students at UC Berkeley.
. This contributed to the separation of the departments of civil engineering and astronomy in the mid 1890s, with the Students' Observatory becoming the home of the Berkeley Astronomy Department.
In 1898, Armin Otto Leuschner was appointed the director of the Students' Observatory, a post that he held until his retirement in 1938. During this time, "the observatory became a center for the computation of the orbits of comets, minor planets, and satellites." Astronomer Simon Newcomb
said that Leuschner organized the department and observatory into "a thorough school of astronomy, than which [...] there is none better." After he stepped down, the observatory was directed by a series of well regarded astronomers, including Otto Struve
from 1950–59 and Louis G. Henyey
from 1959–64. The Students' Observatory was renamed Leuschner Observatory by the Regents of the University of California in 1951 in honor of A. O. Leuschner. The Space Sciences Lab, which operates SETI
, began operations in 1960 at Leuschner Observatory until a permanent home in the Berkeley hills was completed in 1966.
In 1965, the observatory was relocated a short distance east of the Berkeley campus in the hills of Lafayette, California
, on the 283 acres (1.1 km²) Russell Reservation. In 1968, the observatory was equipped with a new 30 inches (762 mm) Ritchey-Chretien telescope
built by Tinsley Laboratories. Since, the observatory has been used as a testing ground for a variety of experiments and instruments. The predecessor to the Katzman Automatic Imaging Telescope
was tested at Leuschner Observatory in the early 1990s, and in the early 2000s, the first prototype of the telescopes used at the Allen Telescope Array
was unveiled at Leuschner. As of 2010, Leuschner Observatory's 30 inches (762 mm) telescope is regularly used in undergraduate astronomical instruction, while the 20 inches (508 mm) telescope has been decommissioned and is in disrepair.
s, one with a 30 inches (762 mm) diameter and the other with a 20 inches (508 mm) diameter. As of 2010, the 20 inches (508 mm) telescope is not usable, and the 30 inches (762 mm) telescope is undergoing upgrades. The 30 inches (762 mm) telescope is of Ritchey-Chretien design, and is equipped with both a charge coupled device (CCD) for observations in visible light and an infrared
detector that was fabricated in 2000 in order to create an infrared laboratory course for undergraduate students at UC Berkeley. Both optical telescopes are also outfitted with control systems which allow them be automated, meaning observations are made with minimal human intervention.
. The telescope was one of the prototypes for the Allen Telescope Array that were tested at Leuschner, and has since been used in the undergraduate radio astronomy lab. The telescope operates between 1320–1740 MHz
and uses an 8192 element spectrometer
with spectral resolution
of about 1.5 kHz and a 12 MHz bandwidth. The operating range allows for it to be used to observe the 21-cm hydrogen line
as well as hydroxyl
lines from astrophysical maser
s.
in order to determine orbit
s for newly discovered comet
s. When Clyde Tombaugh
reported the discovery of Pluto
in 1930, Leuschner began observing it using the instruments at Students' Observatory to determine its orbit. Within months of its discovery, Leuschner cast the first doubt on Pluto's status as a planet, suggesting instead that it was unclear whether Pluto was a large asteroid
, a planet
, or a comet. Using a few weeks of observation at the Students' Observatory, he and his students Fred Whipple and E. C. Bower found determined the orbital elements for Pluto and an upper limit of one half the mass of Earth
. This mass meant Pluto was insufficiently massive to be the Planet X
thought to cause discrepancies between the predicted and observed orbit of Neptune
.
surveys. The Berkeley Automated Supernova Search, led by Saul Perlmutter
, who went on to head the Supernova Cosmology Project
, used the 30 inches (762 mm) telescope at Leuschner to scan the skies nightly for supernova
. The Leuschner Observatory Supernova Search (LOSS) began in 1992, as the Berkeley Automated Imaging Telescope (BAIT) also searched for supernova, in this case under Alex Filippenko. Both were used as testing grounds for automated searches at other sites, with BAIT eventually being succeeded by the Katzman Automatic Imaging Telescope
located at Lick Observatory. While LOSS operated at Leuschner, it discovered SN 1992bt, SN 1993G, SN 1993R, SN 1993X, SN 1993Z, SN 1994D
, and SN 1994ae.
The 30 inches (762 mm) telescope was also used as part of a program called Hands-On Universe that allows elementary and high school students to request observations on the telescope. In late March 1994, two high school students in Oil City
, Pennsylvania
, requested observations of the Whirlpool Galaxy
. When astronomers discovered SN 1994I
in the Whirlpool Galaxy a few days later, they realized that the observations made with the 30 inches (762 mm) telescope at Leuschner had captured the earliest images of the supernova. Even more, the images provided astronomers some of "earliest supernovae light curve data on record."
experiment, carried out under the direction of UC Berkeley astronomer Dan Werthimer
. The program consists of a targeted search for bright pulses of short duration around 2500 nearby star
s using the automated 30 inches (762 mm) telescope. Similar efforts are carried out at Lick Observatory
using the Nickel telescope.
reported observing two strange objects. A graduate student at Berkeley used the 30 inches (762 mm) telescope at Leuschner Observatory to make the first identification of the two objects as being elliptical galaxies
. Once it was known what they were, the two objects were named Maffei 1
and Maffei 2
after their discover. In identifying the nature of the objects, astronomer
s realized they were very nearby objects, perhaps even belonging to the Local Group
. While eventually membership in the Local Group was ruled out, Maffei 1 is now recognized as being the nearest major elliptical galaxy.
and Jack Sepkoski
suggested that extinction
events on Earth followed a periodic trend. Richard Muller
, a professor of physics at Berkeley, was part of a team that suggested that the Sun had an unseen stellar companion
which caused this periodicity, with this hypothetical companion being dubbed Nemesis
. Muller was already involved in the automated supernova searches underway at Leuschner, and began the search for Nemesis using the optical telescopes at Leuschner Observatory.
University of California, Berkeley
The University of California, Berkeley , is a teaching and research university established in 1868 and located in Berkeley, California, USA...
. The observatory was built in 1886 on the Berkeley campus. For many years, it was directed by Armin Otto Leuschner
Armin Otto Leuschner
Armin Otto Leuschner was an American astronomer and educator.Leuschner was born in the US but raised in Germany. He returned to the US for university studies, graduating from the University of Michigan in 1888 with a degree in mathematics...
, for whom the observatory was renamed in 1951. In 1965, it was relocated to its present home in Lafayette, California
Lafayette, California
Lafayette is a city in Contra Costa County, California, United States. As of the 2010 census, the city's population was 23,893. It was named after the Marquis de Lafayette, a French military hero of the American Revolutionary War...
, approximately 10 miles (16.1 km) east of the Berkeley campus.
Presently, Leuschner Observatory has two operating telescopes. One is a 30 inches (762 mm) optical telescope
Optical telescope
An optical telescope is a telescope which is used to gather and focus light mainly from the visible part of the electromagnetic spectrum for directly viewing a magnified image for making a photograph, or collecting data through electronic image sensors....
, equipped with a CCD for observations in visible light and an infrared
Infrared
Infrared light is electromagnetic radiation with a wavelength longer than that of visible light, measured from the nominal edge of visible red light at 0.74 micrometres , and extending conventionally to 300 µm...
detector used for infrared astronomy
Infrared astronomy
Infrared astronomy is the branch of astronomy and astrophysics that studies astronomical objects visible in infrared radiation. The wavelength of infrared light ranges from 0.75 to 300 micrometers...
. The other is a 4-meter radio
Radio Wave
Radio Wave may refer to:*Radio frequency*Radio Wave 96.5, a radio station in Blackpool, UK...
dish used for an undergraduate radio astronomy
Radio astronomy
Radio astronomy is a subfield of astronomy that studies celestial objects at radio frequencies. The initial detection of radio waves from an astronomical object was made in the 1930s, when Karl Jansky observed radiation coming from the Milky Way. Subsequent observations have identified a number of...
course. The observatory has been used to perform professional astronomy
Astronomy
Astronomy is a natural science that deals with the study of celestial objects and phenomena that originate outside the atmosphere of Earth...
research, such as orbit
Orbit
In physics, an orbit is the gravitationally curved path of an object around a point in space, for example the orbit of a planet around the center of a star system, such as the Solar System...
determination of small solar system bodies in the early 1900s, and supernova
Supernova
A supernova is a stellar explosion that is more energetic than a nova. It is pronounced with the plural supernovae or supernovas. Supernovae are extremely luminous and cause a burst of radiation that often briefly outshines an entire galaxy, before fading from view over several weeks or months...
surveys in the 1980s and 1990s. It has also served as a primary tool in the education of graduate
Graduate school
A graduate school is a school that awards advanced academic degrees with the general requirement that students must have earned a previous undergraduate degree...
and undergraduate students at UC Berkeley.
History
The Students' Observatory was constructed in 1886 on the Berkeley campus, with the original funds provided by the California legislature in order for the observatory to provide practical training to civil engineers. Very quickly, the Students' Observatory became seen as a training ground for students studying astronomy, so that they would be better prepared to go on to use the facilities at Lick ObservatoryLick Observatory
The Lick Observatory is an astronomical observatory, owned and operated by the University of California. It is situated on the summit of Mount Hamilton, in the Diablo Range just east of San Jose, California, USA...
. This contributed to the separation of the departments of civil engineering and astronomy in the mid 1890s, with the Students' Observatory becoming the home of the Berkeley Astronomy Department.
In 1898, Armin Otto Leuschner was appointed the director of the Students' Observatory, a post that he held until his retirement in 1938. During this time, "the observatory became a center for the computation of the orbits of comets, minor planets, and satellites." Astronomer Simon Newcomb
Simon Newcomb
Simon Newcomb was a Canadian-American astronomer and mathematician. Though he had little conventional schooling, he made important contributions to timekeeping as well as writing on economics and statistics and authoring a science fiction novel.-Early life:Simon Newcomb was born in the town of...
said that Leuschner organized the department and observatory into "a thorough school of astronomy, than which [...] there is none better." After he stepped down, the observatory was directed by a series of well regarded astronomers, including Otto Struve
Otto Struve
Otto Struve was a Russian astronomer. In Russian, his name is sometimes given as Otto Lyudvigovich Struve ; however, he spent most of his life and his entire scientific career in the United States...
from 1950–59 and Louis G. Henyey
Louis G. Henyey
Louis George Henyey was an American astronomer.His parents, Albert and Mary Henyey, were immigrants from Hungary...
from 1959–64. The Students' Observatory was renamed Leuschner Observatory by the Regents of the University of California in 1951 in honor of A. O. Leuschner. The Space Sciences Lab, which operates SETI
SETI
The search for extraterrestrial intelligence is the collective name for a number of activities people undertake to search for intelligent extraterrestrial life. Some of the most well known projects are run by the SETI Institute. SETI projects use scientific methods to search for intelligent life...
, began operations in 1960 at Leuschner Observatory until a permanent home in the Berkeley hills was completed in 1966.
In 1965, the observatory was relocated a short distance east of the Berkeley campus in the hills of Lafayette, California
Lafayette, California
Lafayette is a city in Contra Costa County, California, United States. As of the 2010 census, the city's population was 23,893. It was named after the Marquis de Lafayette, a French military hero of the American Revolutionary War...
, on the 283 acres (1.1 km²) Russell Reservation. In 1968, the observatory was equipped with a new 30 inches (762 mm) Ritchey-Chretien telescope
Ritchey-Chrétien telescope
A Ritchey–Chrétien telescope is a specialized Cassegrain telescope designed to eliminate coma, thus providing a large field of view compared to a more conventional configuration. An RCT has a hyperbolic primary and a hyperbolic secondary mirror. It was invented in the early 1910s by American...
built by Tinsley Laboratories. Since, the observatory has been used as a testing ground for a variety of experiments and instruments. The predecessor to the Katzman Automatic Imaging Telescope
Katzman Automatic Imaging Telescope
The Katzman Automatic Imaging Telescope is an automated telescope used in the search for supernovae.The KAIT is a computer-controlled reflecting telescope with a 76 cm mirror and a CCD camera to take pictures. It is located at the Lick Observatory near San Jose, California.KAIT can take close to...
was tested at Leuschner Observatory in the early 1990s, and in the early 2000s, the first prototype of the telescopes used at the Allen Telescope Array
Allen Telescope Array
The Allen Telescope Array , formerly known as the One Hectare Telescope , was a joint effort by the SETI Institute and the Radio Astronomy Laboratory at the University of California, Berkeley to construct a radio interferometer that is dedicated to astronomical observations and a simultaneous...
was unveiled at Leuschner. As of 2010, Leuschner Observatory's 30 inches (762 mm) telescope is regularly used in undergraduate astronomical instruction, while the 20 inches (508 mm) telescope has been decommissioned and is in disrepair.
Optical/Infrared
Leuschner Observatory houses two optical telescopeOptical telescope
An optical telescope is a telescope which is used to gather and focus light mainly from the visible part of the electromagnetic spectrum for directly viewing a magnified image for making a photograph, or collecting data through electronic image sensors....
s, one with a 30 inches (762 mm) diameter and the other with a 20 inches (508 mm) diameter. As of 2010, the 20 inches (508 mm) telescope is not usable, and the 30 inches (762 mm) telescope is undergoing upgrades. The 30 inches (762 mm) telescope is of Ritchey-Chretien design, and is equipped with both a charge coupled device (CCD) for observations in visible light and an infrared
Infrared
Infrared light is electromagnetic radiation with a wavelength longer than that of visible light, measured from the nominal edge of visible red light at 0.74 micrometres , and extending conventionally to 300 µm...
detector that was fabricated in 2000 in order to create an infrared laboratory course for undergraduate students at UC Berkeley. Both optical telescopes are also outfitted with control systems which allow them be automated, meaning observations are made with minimal human intervention.
Radio
Leuschner Observatory is home to a single 3.6 m radio telescopeRadio telescope
A radio telescope is a form of directional radio antenna used in radio astronomy. The same types of antennas are also used in tracking and collecting data from satellites and space probes...
. The telescope was one of the prototypes for the Allen Telescope Array that were tested at Leuschner, and has since been used in the undergraduate radio astronomy lab. The telescope operates between 1320–1740 MHz
Hertz
The hertz is the SI unit of frequency defined as the number of cycles per second of a periodic phenomenon. One of its most common uses is the description of the sine wave, particularly those used in radio and audio applications....
and uses an 8192 element spectrometer
Spectrometer
A spectrometer is an instrument used to measure properties of light over a specific portion of the electromagnetic spectrum, typically used in spectroscopic analysis to identify materials. The variable measured is most often the light's intensity but could also, for instance, be the polarization...
with spectral resolution
Spectral resolution
The spectral resolution of a spectrograph, or, more generally, of a frequency spectrum, is a measure of its ability to resolve features in the electromagnetic spectrum...
of about 1.5 kHz and a 12 MHz bandwidth. The operating range allows for it to be used to observe the 21-cm hydrogen line
Hydrogen line
The hydrogen line, 21 centimeter line or HI line refers to the electromagnetic radiation spectral line that is created by a change in the energy state of neutral hydrogen atoms. This electromagnetic radiation is at the precise frequency of 1420.40575177 MHz, which is equivalent to the vacuum...
as well as hydroxyl
Hydroxyl
A hydroxyl is a chemical group containing an oxygen atom covalently bonded with a hydrogen atom. In inorganic chemistry, the hydroxyl group is known as the hydroxide ion, and scientists and reference works generally use these different terms though they refer to the same chemical structure in...
lines from astrophysical maser
Astrophysical maser
An astrophysical maser is a naturally occurring source of stimulated spectral line emission, typically in the microwave portion of the electromagnetic spectrum...
s.
Orbit determination
Research at the Students' Observatory under A. O. Leuschner was primarily focused on performing astrometryAstrometry
Astrometry is the branch of astronomy that involves precise measurements of the positions and movements of stars and other celestial bodies. The information obtained by astrometric measurements provides information on the kinematics and physical origin of our Solar System and our Galaxy, the Milky...
in order to determine orbit
Orbit
In physics, an orbit is the gravitationally curved path of an object around a point in space, for example the orbit of a planet around the center of a star system, such as the Solar System...
s for newly discovered comet
Comet
A comet is an icy small Solar System body that, when close enough to the Sun, displays a visible coma and sometimes also a tail. These phenomena are both due to the effects of solar radiation and the solar wind upon the nucleus of the comet...
s. When Clyde Tombaugh
Clyde Tombaugh
Clyde William Tombaugh was an American astronomer. Although he is best known for discovering the dwarf planet Pluto in 1930, the first object to be discovered in what would later be identified as the Kuiper Belt, Tombaugh also discovered many asteroids; he also called for serious scientific...
reported the discovery of Pluto
Pluto
Pluto, formal designation 134340 Pluto, is the second-most-massive known dwarf planet in the Solar System and the tenth-most-massive body observed directly orbiting the Sun...
in 1930, Leuschner began observing it using the instruments at Students' Observatory to determine its orbit. Within months of its discovery, Leuschner cast the first doubt on Pluto's status as a planet, suggesting instead that it was unclear whether Pluto was a large asteroid
Asteroid
Asteroids are a class of small Solar System bodies in orbit around the Sun. They have also been called planetoids, especially the larger ones...
, a planet
Planet
A planet is a celestial body orbiting a star or stellar remnant that is massive enough to be rounded by its own gravity, is not massive enough to cause thermonuclear fusion, and has cleared its neighbouring region of planetesimals.The term planet is ancient, with ties to history, science,...
, or a comet. Using a few weeks of observation at the Students' Observatory, he and his students Fred Whipple and E. C. Bower found determined the orbital elements for Pluto and an upper limit of one half the mass of Earth
Earth mass
Earth mass is the unit of mass equal to that of the Earth. 1 M⊕ = 5.9722 × 1024 kg. Earth mass is often used to describe masses of rocky terrestrial planets....
. This mass meant Pluto was insufficiently massive to be the Planet X
Planets beyond Neptune
Following the discovery of the planet Neptune in 1846, there was considerable speculation that another planet might exist beyond its orbit. The search began in the mid-19th century but culminated at the start of the 20th with Percival Lowell's quest for Planet X...
thought to cause discrepancies between the predicted and observed orbit of Neptune
Neptune
Neptune is the eighth and farthest planet from the Sun in the Solar System. Named for the Roman god of the sea, it is the fourth-largest planet by diameter and the third largest by mass. Neptune is 17 times the mass of Earth and is slightly more massive than its near-twin Uranus, which is 15 times...
.
Supernova
The observatory was for a time home to two automated supernovaSupernova
A supernova is a stellar explosion that is more energetic than a nova. It is pronounced with the plural supernovae or supernovas. Supernovae are extremely luminous and cause a burst of radiation that often briefly outshines an entire galaxy, before fading from view over several weeks or months...
surveys. The Berkeley Automated Supernova Search, led by Saul Perlmutter
Saul Perlmutter
Saul Perlmutter is an American astrophysicist at the Lawrence Berkeley National Laboratory and a professor of physics at the University of California, Berkeley. He is a member of the American Academy of Arts & Sciences, and was elected a Fellow of the American Association for the Advancement of...
, who went on to head the Supernova Cosmology Project
Supernova Cosmology Project
The Supernova Cosmology Project is one of two research teams that determined the likelihood of an accelerating universe and therefore a positive Cosmological constant, using data from the redshift of Type Ia supernovae...
, used the 30 inches (762 mm) telescope at Leuschner to scan the skies nightly for supernova
Supernova
A supernova is a stellar explosion that is more energetic than a nova. It is pronounced with the plural supernovae or supernovas. Supernovae are extremely luminous and cause a burst of radiation that often briefly outshines an entire galaxy, before fading from view over several weeks or months...
. The Leuschner Observatory Supernova Search (LOSS) began in 1992, as the Berkeley Automated Imaging Telescope (BAIT) also searched for supernova, in this case under Alex Filippenko. Both were used as testing grounds for automated searches at other sites, with BAIT eventually being succeeded by the Katzman Automatic Imaging Telescope
Katzman Automatic Imaging Telescope
The Katzman Automatic Imaging Telescope is an automated telescope used in the search for supernovae.The KAIT is a computer-controlled reflecting telescope with a 76 cm mirror and a CCD camera to take pictures. It is located at the Lick Observatory near San Jose, California.KAIT can take close to...
located at Lick Observatory. While LOSS operated at Leuschner, it discovered SN 1992bt, SN 1993G, SN 1993R, SN 1993X, SN 1993Z, SN 1994D
SN 1994D
Supernova 1994D was a Type Ia supernova on the outskirts of galaxy NGC 4526. It was discovered in 1994 by Treffers, Filippenko, Van Dyk, and Richmond using the automated 30-inch telescope at Leuschner Observatory....
, and SN 1994ae.
The 30 inches (762 mm) telescope was also used as part of a program called Hands-On Universe that allows elementary and high school students to request observations on the telescope. In late March 1994, two high school students in Oil City
Oil City
Oil City may refer to:in the United States*Casper, Wyoming, nicknamed "The Oil City"* Oil City, California, community in Kern County, California* Oil City, Kentucky, community in Barren County, Kentucky* Oil City, Louisiana, town in Caddo Parish, Louisiana...
, Pennsylvania
Pennsylvania
The Commonwealth of Pennsylvania is a U.S. state that is located in the Northeastern and Mid-Atlantic regions of the United States. The state borders Delaware and Maryland to the south, West Virginia to the southwest, Ohio to the west, New York and Ontario, Canada, to the north, and New Jersey to...
, requested observations of the Whirlpool Galaxy
Whirlpool Galaxy
The Whirlpool Galaxy is an interacting grand-design spiral galaxy that is estimated to be 23 ± 4 million light-years from the Milky Way Galaxy. in the constellation Canes Venatici...
. When astronomers discovered SN 1994I
SN 1994I
SN 1994I is a Type Ic supernova discovered on April 2, 1994 in the Whirlpool Galaxy by amateur astronomers Tim Puckett and Jerry Armstrong of the Atlanta Astronomy Club. Type Ic supernova are a rare type of supernova that result from the explosion of a very massive star that has shed its outer...
in the Whirlpool Galaxy a few days later, they realized that the observations made with the 30 inches (762 mm) telescope at Leuschner had captured the earliest images of the supernova. Even more, the images provided astronomers some of "earliest supernovae light curve data on record."
SETI
Leuschner Observatory is also home to an optical SETISETI
The search for extraterrestrial intelligence is the collective name for a number of activities people undertake to search for intelligent extraterrestrial life. Some of the most well known projects are run by the SETI Institute. SETI projects use scientific methods to search for intelligent life...
experiment, carried out under the direction of UC Berkeley astronomer Dan Werthimer
Dan Werthimer
Dan Werthimer is co-founder and chief scientist of the SETI@home project and directs other UC Berkeley SETI searches at radio, infrared and visible wavelengths, including the Search for Extra-Terrestrial Radio Emissions from Nearby Developed Intelligent Populations...
. The program consists of a targeted search for bright pulses of short duration around 2500 nearby star
Star
A star is a massive, luminous sphere of plasma held together by gravity. At the end of its lifetime, a star can also contain a proportion of degenerate matter. The nearest star to Earth is the Sun, which is the source of most of the energy on Earth...
s using the automated 30 inches (762 mm) telescope. Similar efforts are carried out at Lick Observatory
Lick Observatory
The Lick Observatory is an astronomical observatory, owned and operated by the University of California. It is situated on the summit of Mount Hamilton, in the Diablo Range just east of San Jose, California, USA...
using the Nickel telescope.
Maffei 1 and 2
In 1968, Italian astronomer Paolo MaffeiPaolo Maffei
Paolo Maffei was an Italian astronomer and science writer.He was born in Foligno and he has been former director of the Catania Observatory and an astronomer at Arcetri, Bologna, Asiago and Hamburg...
reported observing two strange objects. A graduate student at Berkeley used the 30 inches (762 mm) telescope at Leuschner Observatory to make the first identification of the two objects as being elliptical galaxies
Elliptical galaxy
An elliptical galaxy is a galaxy having an approximately ellipsoidal shape and a smooth, nearly featureless brightness profile. They range in shape from nearly spherical to highly flat and in size from hundreds of millions to over one trillion stars...
. Once it was known what they were, the two objects were named Maffei 1
Maffei 1
Maffei 1 is a giant elliptical galaxy in the constellation Cassiopeia. It is the closest giant elliptical galaxy to the Milky Way. Once believed to be a member of the Local Group, it is now known to belong to the IC 342/Maffei Group...
and Maffei 2
Maffei 2
Maffei 2 is an intermediate spiral galaxy about 10 million light-years away in the constellation Cassiopeia. Maffei 2 and Maffei 1 were both discovered by Paolo Maffei in 1968 from their infrared emission. Maffei 2 lies in the Zone of Avoidance and is about 99.5% obscured by the Milky Way's...
after their discover. In identifying the nature of the objects, astronomer
Astronomer
An astronomer is a scientist who studies celestial bodies such as planets, stars and galaxies.Historically, astronomy 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...
s realized they were very nearby objects, perhaps even belonging to the Local Group
Local Group
The Local Group is the group of galaxies that includes Earth's galaxy, the Milky Way. The group comprises more than 30 galaxies , with its gravitational center located somewhere between the Milky Way and the Andromeda Galaxy...
. While eventually membership in the Local Group was ruled out, Maffei 1 is now recognized as being the nearest major elliptical galaxy.
Nemesis
In 1984, paleontologists David M. RaupDavid M. Raup
David M. Raup is a University of Chicago paleontologist. Raup studied the fossil record and the diversity of life on Earth. Raup contributed to the knowledge of extinction events along with his colleague Jack Sepkoski...
and Jack Sepkoski
Jack Sepkoski
J. John Sepkoski Jr., , was a University of Chicago paleontologist. Sepkoski studied the fossil record and the diversity of life on Earth. Sepkoski and David Raup contributed to the knowledge of extinction events...
suggested that extinction
Extinction
In biology and ecology, extinction is the end of an organism or of a group of organisms , normally a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and recover may have been lost before this point...
events on Earth followed a periodic trend. Richard Muller
Richard Müller
Richard Müller/Muller/Mueller may refer to:* Richard Müller , German chemist* Richard Müller , Slovak singer...
, a professor of physics at Berkeley, was part of a team that suggested that the Sun had an unseen stellar companion
Binary star
A binary star is a star system consisting of two stars orbiting around their common center of mass. The brighter star is called the primary and the other is its companion star, comes, or secondary...
which caused this periodicity, with this hypothetical companion being dubbed Nemesis
Nemesis (star)
Nemesis is a hypothetical hard-to-detect red dwarf star, white dwarf star or brown dwarf, originally postulated in 1984 to be orbiting the Sun at a distance of about 95,000 AU , somewhat beyond the Oort cloud, to explain a perceived cycle of mass extinctions in the geological record, which seem to...
. Muller was already involved in the automated supernova searches underway at Leuschner, and began the search for Nemesis using the optical telescopes at Leuschner Observatory.