Leuschner Observatory, originally called the Students' Observatory, is an observatory jointly operated by the
University of California, Berkeley
The University of California, Berkeley (UC Berkeley, Berkeley, Cal, or California) is a public land-grant research university in Berkeley, California. Established in 1868 as the University of California, it is the state's first land-grant u ...
and
San Francisco State University
San Francisco State University (commonly referred to as San Francisco State, SF State and SFSU) is a public research university in San Francisco. As part of the 23-campus California State University system, the university offers 118 different b ...
. The observatory was built in 1886 on the Berkeley campus. For many years, it was directed by
Armin Otto Leuschner
Armin Otto Leuschner (January 16, 1868 – April 22, 1953) was an American astronomer and educator.
Biography
Leuschner was born on January 16, 1868, in the United States but raised in Germany. He returned to the United States for univers ...
, for whom the observatory was renamed in 1951. In 1965, it was relocated to its present home in
Lafayette, California
Lafayette (formerly La Fayette) is a city in Contra Costa County, California, United States. As of 2020, the city's population was 25,391. It was named after the Marquis de Lafayette, a French military officer of the American Revolutionary War. ...
, approximately east of the Berkeley campus. In 2012, the physics and astronomy department of
San Francisco State University
San Francisco State University (commonly referred to as San Francisco State, SF State and SFSU) is a public research university in San Francisco. As part of the 23-campus California State University system, the university offers 118 different b ...
became a partner.
Presently, Leuschner Observatory has two operating telescopes. One is a
optical telescope
An optical telescope is a telescope that gathers and focuses light mainly from the visible part of the electromagnetic spectrum, to create a magnified image for direct visual inspection, to make a photograph, or to collect data through electro ...
, equipped with a
CCD for observations in
visible light
Light or visible light is electromagnetic radiation that can be perceived by the human eye. Visible light is usually defined as having wavelengths in the range of 400–700 nanometres (nm), corresponding to frequencies of 750–420 te ...
and an
infrared
Infrared (IR), sometimes called infrared light, is electromagnetic radiation (EMR) with wavelengths longer than those of visible light. It is therefore invisible to the human eye. IR is generally understood to encompass wavelengths from around ...
detector used for
infrared astronomy
Infrared astronomy is a sub-discipline of astronomy which specializes in the observation and analysis of astronomical objects using infrared (IR) radiation. The wavelength of infrared light ranges from 0.75 to 300 micrometers, and falls in betwee ...
. The other is a
radio
Radio is the technology of signaling and communicating using radio waves. Radio waves are electromagnetic waves of frequency between 30 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a transmit ...
dish used for an undergraduate
radio astronomy
Radio astronomy is a subfield of astronomy that studies celestial objects at radio frequencies. The first detection of radio waves from an astronomical object was in 1933, when Karl Jansky at Bell Telephone Laboratories reported radiation coming f ...
course. The observatory has been used to perform professional
astronomy
Astronomy () is a natural science that studies astronomical object, celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and chronology of the Universe, evolution. Objects of interest ...
research, such as
orbit
In celestial mechanics, an orbit is the curved trajectory of an object such as the trajectory of a planet around a star, or of a natural satellite around a planet, or of an artificial satellite around an object or position in space such as a p ...
determination of
small solar system bodies
A small Solar System body (SSSB) is an object in the Solar System that is neither a planet, a dwarf planet, nor a natural satellite. The term was first IAU definition of planet, defined in 2006 by the International Astronomical Union (IAU) as fol ...
in the early 1900s and
supernova
A supernova is a powerful and luminous explosion of a star. It has the plural form supernovae or supernovas, and is abbreviated SN or SNe. This transient astronomical event occurs during the last evolutionary stages of a massive star or when ...
surveys in the 1980s and 1990s. It has also served as a primary tool in the education of
graduate and
undergraduate
Undergraduate education is education conducted after secondary education and before postgraduate education. It typically includes all postsecondary programs up to the level of a bachelor's degree. For example, in the United States, an entry-lev ...
students at UC Berkeley.
History
![Leuschner plaque](https://upload.wikimedia.org/wikipedia/commons/6/60/Leuschner_plaque.jpg)
The Students' Observatory was constructed in 1886 on the Berkeley campus, with the original funds provided by the
California legislature
The California State Legislature is a bicameral state legislature consisting of a lower house, the California State Assembly, with 80 members; and an upper house, the California State Senate, with 40 members. Both houses of the Legisla ...
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 Observatory
The Lick Observatory is an astronomical observatory owned and operated by the University of California. It is on the summit of Mount Hamilton, in the Diablo Range just east of San Jose, California, United States. The observatory is managed by th ...
. 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
Armin Otto Leuschner (January 16, 1868 – April 22, 1953) was an American astronomer and educator.
Biography
Leuschner was born on January 16, 1868, in the United States but raised in Germany. He returned to the United States for univers ...
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 (March 12, 1835 – July 11, 1909) was a Canadian–American astronomer, applied mathematician, and autodidactic polymath. He served as Professor of Mathematics in the United States Navy and at Johns Hopkins University. Born in Nov ...
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 (August 12, 1897 – April 6, 1963) was a Russian-American astronomer of Baltic German origins. In Russian, his name is sometimes given as Otto Lyudvigovich Struve (Отто Людвигович Струве); however, he spent most o ...
from 1950–59 and
Louis G. Henyey
Louis George Henyey (February 3, 1910 – February 18, 1970) was an American astronomer.
His parents, Albert and Mary Henyey, were immigrants from Hungary. Louis George Henyey married Elizabeth Rose Belak, born in Budapest, on April 28, 1934; ...
from 1959–64. The Students' Observatory was renamed Leuschner Observatory by the
Regents
A regent (from Latin : ruling, governing) is a person appointed to govern a state '' pro tempore'' (Latin: 'for the time being') because the monarch is a minor, absent, incapacitated or unable to discharge the powers and duties of the monarchy ...
of the University of California in 1951 in honor of A. O. Leuschner.
The
Space Sciences Lab
Space is the boundless three-dimensional extent in which objects and events have relative position and direction. In classical physics, physical space is often conceived in three linear dimensions, although modern physicists usually conside ...
, which operates
SETI
The search for extraterrestrial intelligence (SETI) is a collective term for scientific searches for intelligent extraterrestrial life, for example, monitoring electromagnetic radiation for signs of transmissions from civilizations on other p ...
, 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 (formerly La Fayette) is a city in Contra Costa County, California, United States. As of 2020, the city's population was 25,391. It was named after the Marquis de Lafayette, a French military officer of the American Revolutionary War. ...
, on the Russell Reservation. In 1968, the observatory was equipped with a new
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
The Katzman Automatic Imaging Telescope (KAIT) is an automated telescope used in the search for supernovae.
The telescope had a first light in 1998, and is a noted robotic telescope. It had first recorded data in August 1996, and was formally ded ...
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.
Leuschner Observatory's telescope continues to be regularly used in undergraduate astronomical instruction, while the telescope was decommissioned and is in disrepair. In 2012, the physics and astronomy department of
San Francisco State University
San Francisco State University (commonly referred to as San Francisco State, SF State and SFSU) is a public research university in San Francisco. As part of the 23-campus California State University system, the university offers 118 different b ...
bought into the telescope. SF State and UC Berkeley staff jointly refurbished and upgraded the motors and control system of the larger telescope; SF State also installed a remote observing station based in its frequently fog-laden San Francisco campus.
Instruments
Optical/infrared
Leuschner Observatory houses two
optical telescope
An optical telescope is a telescope that gathers and focuses light mainly from the visible part of the electromagnetic spectrum, to create a magnified image for direct visual inspection, to make a photograph, or to collect data through electro ...
s, one with a diameter and the other with a diameter. As of 2010, the telescope is not usable, and the telescope is undergoing upgrades. The telescope is of Ritchey-Chretien design, and is equipped with both a
charge coupled device (CCD) for observations in
visible light
Light or visible light is electromagnetic radiation that can be perceived by the human eye. Visible light is usually defined as having wavelengths in the range of 400–700 nanometres (nm), corresponding to frequencies of 750–420 te ...
and an
infrared
Infrared (IR), sometimes called infrared light, is electromagnetic radiation (EMR) with wavelengths longer than those of visible light. It is therefore invisible to the human eye. IR is generally understood to encompass wavelengths from around ...
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
radio telescope
A radio telescope is a specialized antenna and radio receiver used to detect radio waves from astronomical radio sources in the sky. Radio telescopes are the main observing instrument used in radio astronomy, which studies the radio frequency ...
. 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
The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), equivalent to one event (or cycle) per second. The hertz is an SI derived unit whose expression in terms of SI base units is s−1, meaning that one he ...
and uses an 8192 element
spectrometer
A spectrometer () is a scientific instrument used to separate and measure spectral components of a physical phenomenon. Spectrometer is a broad term often used to describe instruments that measure a continuous variable of a phenomenon where the ...
with
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. It is usually denoted by \Delta\lambda, and is closely related to the resolvi ...
of about 1.5 kHz and a 12 MHz
bandwidth
Bandwidth commonly refers to:
* Bandwidth (signal processing) or ''analog bandwidth'', ''frequency bandwidth'', or ''radio bandwidth'', a measure of the width of a frequency range
* Bandwidth (computing), the rate of data transfer, bit rate or thr ...
. The operating range allows for it to be used to observe the 21-cm
hydrogen line
The hydrogen line, 21 centimeter line, or H I line is the electromagnetic radiation spectral line that is created by a change in the energy state of neutral hydrogen atoms. This electromagnetic radiation has a precise frequency of , w ...
as well as
hydroxyl
In chemistry, a hydroxy or hydroxyl group is a functional group with the chemical formula and composed of one oxygen atom covalently bonded to one hydrogen atom. In organic chemistry, alcohols and carboxylic acids contain one or more hydroxy ...
lines from
astrophysical maser
An astrophysical maser is a naturally occurring source of stimulated spectral line emission, typically in the microwave portion of the electromagnetic spectrum. This emission may arise in molecular clouds, comets, planetary atmospheres, stellar at ...
s.
Research and discoveries
Orbit determination
Research at the Students' Observatory under A. O. Leuschner was primarily focused on performing
astrometry
Astrometry is a branch of astronomy that involves precise measurements of the positions and movements of stars and other celestial bodies. It provides the kinematics and physical origin of the Solar System and this galaxy, the Milky Way.
His ...
in order to determine
orbit
In celestial mechanics, an orbit is the curved trajectory of an object such as the trajectory of a planet around a star, or of a natural satellite around a planet, or of an artificial satellite around an object or position in space such as a p ...
s for newly discovered
comet
A comet is an icy, small Solar System body that, when passing close to the Sun, warms and begins to release gases, a process that is called outgassing. This produces a visible atmosphere or coma, and sometimes also a tail. These phenomena ar ...
s. When
Clyde Tombaugh
Clyde William Tombaugh (February 4, 1906 January 17, 1997) was an American astronomer. He discovered Pluto in 1930, the first object to be discovered in what would later be identified as the Kuiper belt. At the time of discovery, Pluto was cons ...
reported the discovery of
Pluto
Pluto (minor-planet designation: 134340 Pluto) is a dwarf planet in the Kuiper belt, a ring of trans-Neptunian object, bodies beyond the orbit of Neptune. It is the ninth-largest and tenth-most-massive known object to directly orbit the S ...
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
An asteroid is a minor planet of the inner Solar System. Sizes and shapes of asteroids vary significantly, ranging from 1-meter rocks to a dwarf planet almost 1000 km in diameter; they are rocky, metallic or icy bodies with no atmosphere.
...
, a
planet
A planet is a large, rounded astronomical body that is neither a star nor its remnant. The best available theory of planet formation is the nebular hypothesis, which posits that an interstellar cloud collapses out of a nebula to create a you ...
, or a comet.
Using a few weeks of observation at the Students' Observatory, he and his students
Fred Whipple
Fred Lawrence Whipple (November 5, 1906 – August 30, 2004) was an American astronomer, who worked at the Harvard College Observatory for more than 70 years. Amongst his achievements were asteroid and comet discoveries, the " dirty snowball" h ...
and E. C. Bower determined the
orbital element
Orbital elements are the parameters required to uniquely identify a specific orbit. In celestial mechanics these elements are considered in two-body systems using a Kepler orbit. There are many different ways to mathematically describe the same ...
s 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
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 and continued at the start of the 20th with Percival Lowell's ...
thought to cause discrepancies between the predicted and observed orbit of
Neptune
Neptune is the eighth planet from the Sun and the farthest known planet in the Solar System. It is the fourth-largest planet in the Solar System by diameter, the third-most-massive planet, and the densest giant planet. It is 17 times ...
.
Supernova
The observatory was for a time home to two automated
supernova
A supernova is a powerful and luminous explosion of a star. It has the plural form supernovae or supernovas, and is abbreviated SN or SNe. This transient astronomical event occurs during the last evolutionary stages of a massive star or when ...
surveys. The Berkeley Automated Supernova Search, led by
Saul Perlmutter
Saul Perlmutter (born September 22, 1959) is a U.S. astrophysicist at the Lawrence Berkeley National Laboratory and a professor of physics at the University of California, Berkeley. He is a member of both the American Academy of Arts & Sciences ...
, who went on to head the
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. The project is headed by S ...
, used the telescope at Leuschner to scan the skies nightly for
supernova
A supernova is a powerful and luminous explosion of a star. It has the plural form supernovae or supernovas, and is abbreviated SN or SNe. This transient astronomical event occurs during the last evolutionary stages of a massive star or when ...
.
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
Alexei Vladimir "Alex" Filippenko (; born July 25, 1958) is an American astrophysicist and professor of astronomy at the University of California, Berkeley. Filippenko graduated from Dos Pueblos High School in Goleta, California. He received a Ba ...
.
Both were used as testing grounds for automated searches at other sites, with BAIT eventually being succeeded by the
Katzman Automatic Imaging Telescope
The Katzman Automatic Imaging Telescope (KAIT) is an automated telescope used in the search for supernovae.
The telescope had a first light in 1998, and is a noted robotic telescope. It had first recorded data in August 1996, and was formally ded ...
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 was a Type Ia supernova event in the outskirts of galaxy NGC 4526. It was offset by west and south of the galaxy center and positioned near a prominent dust lane. It was caused by the explosion of a white dwarf star composed of carbon ...
, and
SN 1994ae.
The 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
Pennsylvania (; ( Pennsylvania Dutch: )), officially the Commonwealth of Pennsylvania, is a state spanning the Mid-Atlantic, Northeastern, Appalachian, and Great Lakes regions of the United States. It borders Delaware to its southeast, ...
, requested observations of the
Whirlpool Galaxy
The Whirlpool Galaxy, also known as Messier 51a, M51a, and NGC 5194, is an interacting grand-design spiral galaxy with a Seyfert 2 active galactic nucleus.
It lies in the constellation Canes Venatici, and was the first galaxy to be classifie ...
. When astronomers discovered
SN 1994I in the Whirlpool Galaxy a few days later, they realized that the observations made with the 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
SETI
The search for extraterrestrial intelligence (SETI) is a collective term for scientific searches for intelligent extraterrestrial life, for example, monitoring electromagnetic radiation for signs of transmissions from civilizations on other p ...
experiment, carried out under the direction of UC Berkeley astronomer
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 Int ...
. The program consists of a targeted search for bright pulses of short duration around 2500 nearby
star
A star is an astronomical object comprising a luminous spheroid of plasma (physics), plasma held together by its gravity. The List of nearest stars and brown dwarfs, nearest star to Earth is the Sun. Many other stars are visible to the naked ...
s using the automated telescope.
Similar efforts are carried out at
Lick Observatory
The Lick Observatory is an astronomical observatory owned and operated by the University of California. It is on the summit of Mount Hamilton, in the Diablo Range just east of San Jose, California, United States. The observatory is managed by th ...
using the Nickel telescope.
The first optical probe SETI study was also conducted at Leuschner in 197
Maffei 1 and 2
In 1968, Italian astronomer
Paolo Maffei
Paolo Maffei (2 January 1926 – 1 March 2009) was an Italian astrophysicist and science writer.
He was born in Arezzo and was director of the Catania Observatory and an astronomer at Arcetri, Bologna, Asiago and Hamburg. He studied ...
reported observing two strange objects. A graduate student at Berkeley used the telescope at Leuschner Observatory to make the first identification of the two objects as being
elliptical galaxies
An elliptical galaxy is a type of galaxy with an approximately ellipsoidal shape and a smooth, nearly featureless image. They are one of the four main classes of galaxy described by Edwin Hubble in his Hubble sequence and 1936 work ''The Real ...
.
Once it was known what they were, the two objects were named
Maffei 1
Maffei 1 is a massive elliptical galaxy in the constellation Cassiopeia. Once believed to be a member of the Local Group of galaxies, it is now known to belong to a separate group, the IC 342/Maffei Group. It was named after Paolo Maffei, who ...
and
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 Avoidan ...
after their discover. In identifying the nature of the objects,
astronomer
An astronomer is a scientist in the field of astronomy who focuses their studies on a specific question or field outside the scope of Earth. They observe astronomical objects such as stars, planets, natural satellite, moons, comets and galaxy, g ...
s realized they were very nearby objects, perhaps even belonging to the
Local Group
The Local Group is the galaxy group that includes the Milky Way.
It has a total diameter of roughly , and a total mass of the order of .
It consists of two collections of galaxies in a "dumbbell" shape: the Milky Way and its satellites form ...
.
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,
paleontologist
Paleontology (), also spelled palaeontology or palæontology, is the scientific study of life that existed prior to, and sometimes including, the start of the Holocene epoch (roughly 11,700 years before present). It includes the study of fossi ...
s
David M. Raup and
Jack Sepkoski
Joseph John Sepkoski Jr. (July 26, 1948 – May 1, 1999) 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 is the termination of a kind of organism or of a group of kinds (taxon), usually 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 ...
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
In ancient Greek religion, Nemesis, also called Rhamnousia or Rhamnusia ( grc, Ῥαμνουσία, Rhamnousía, the goddess of Rhamnous), was the goddess who personifies retribution, a central concept in the Greek world view.
Etymology
The n ...
. 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.
See also
*
List of astronomical observatories
This is a list of astronomical observatories ordered by name, along with initial dates of operation (where an accurate date is available) and location. The list also includes a final year of operation for many observatories that are no longer in ...
*
Lists of telescopes
This is a list of lists of telescopes.
*List of astronomical interferometers at visible and infrared wavelengths
*List of astronomical observatories
*List of highest astronomical observatories
*List of large optical telescopes
*List of largest i ...
References
{{Good article
Astronomical observatories in California
University of California, Berkeley buildings
Lafayette, California
Buildings and structures in Contra Costa County, California
1886 establishments in California