Mary Lea Heger
   HOME
*





Mary Lea Heger
Mary Lea Heger (July 13, 1897 – July 13, 1983, later Mary Lea Shane) was an American astronomer who made important discoveries on the interstellar medium. She later founded the Lick Observatory Archives located in the Dean E. McHenry Library. In 1982, her monument at Lick was renamed the Mary Lea Shane Archives of Lick Observatory. Education and career She was born in Wilmington, Delaware. During childhood, Heger's family moved west to Belvedere on the San Francisco Bay, where she spent her youth. Heger received her bachelor's degree in 1919 from the University of California, Berkeley, becoming a graduate student in astronomy. After marrying C. Donald Shane in 1920 she completed her PhD in 1924, writing a thesis under the supervision of W. W. Campbell at Lick Observatory that was one of the first papers to recognize the sharp, stationary Na I absorption lines in the spectra of distant binaries as interstellar in origin. She was also the discoverer of the diffuse interstell ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Interstellar Medium
In astronomy, the interstellar medium is the matter and radiation that exist in the space between the star systems in a galaxy. This matter includes gas in ionic, atomic, and molecular form, as well as dust and cosmic rays. It fills interstellar space and blends smoothly into the surrounding intergalactic space. The energy that occupies the same volume, in the form of electromagnetic radiation, is the interstellar radiation field. The interstellar medium is composed of multiple phases distinguished by whether matter is ionic, atomic, or molecular, and the temperature and density of the matter. The interstellar medium is composed, primarily, of hydrogen, followed by helium with trace amounts of carbon, oxygen, and nitrogen. The thermal pressures of these phases are in rough equilibrium with one another. Magnetic fields and turbulent motions also provide pressure in the ISM, and are typically more important, dynamically, than the thermal pressure is. In the interstellar medium, ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

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 the University of California Observatories, with headquarters on the University of California, Santa Cruz campus, where its scientific staff moved in the mid-1960s. It is named after James Lick. The first new moon of Jupiter to be identified since the time of Galileo was discovered at this observatory; Amalthea, the planet's fifth moon, was discovered at this observatory in 1892. Early history Lick Observatory is the world's first permanently occupied mountain-top observatory. The observatory, in a Classical Revival style structure, was constructed between 1876 and 1887, from a bequest from James Lick of $700,000, . Lick, originally a carpenter and piano maker, had arrived from Peru in San Francisco, California, in late 1847; after ac ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Wilmington, Delaware
Wilmington ( Lenape: ''Paxahakink /'' ''Pakehakink)'' is the largest city in the U.S. state of Delaware. The city was built on the site of Fort Christina, the first Swedish settlement in North America. It lies at the confluence of the Christina River and Brandywine Creek, near where the Christina flows into the Delaware River. It is the county seat of New Castle County and one of the major cities in the Delaware Valley metropolitan area. Wilmington was named by Proprietor Thomas Penn after his friend Spencer Compton, Earl of Wilmington, who was prime minister during the reign of George II of Great Britain. At the 2020 census, the city's population was 70,898. The Wilmington Metropolitan Division, comprising New Castle County, Delaware, Cecil County, Maryland and Salem County, New Jersey, had an estimated 2016 population of 719,887. Wilmington is part of the Delaware Valley metropolitan statistical area, which also includes Philadelphia, Reading, Camden, and other urban are ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

San Francisco Bay
San Francisco Bay is a large tidal estuary in the U.S. state of California, and gives its name to the San Francisco Bay Area. It is dominated by the big cities of San Francisco, San Jose, and Oakland. San Francisco Bay drains water from approximately 40 percent of California. Water from the Sacramento and San Joaquin rivers, and from the Sierra Nevada mountains, flow into Suisun Bay, which then travels through the Carquinez Strait to meet with the Napa River at the entrance to San Pablo Bay, which connects at its south end to San Francisco Bay. It then connects to the Pacific Ocean via the Golden Gate strait. However, this entire group of interconnected bays is often called the ''San Francisco Bay''. The bay was designated a Ramsar Wetland of International Importance on February 2, 2017. Size The bay covers somewhere between , depending on which sub-bays (such as San Pablo Bay), estuaries, wetlands, and so on are included in the measurement. The main part of the bay meas ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

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 university and the founding campus of the University of California system. Its fourteen colleges and schools offer over 350 degree programs and enroll some 31,800 undergraduate and 13,200 graduate students. Berkeley ranks among the world's top universities. A founding member of the Association of American Universities, Berkeley hosts many leading research institutes dedicated to science, engineering, and mathematics. The university founded and maintains close relationships with three national laboratories at Berkeley, Livermore and Los Alamos, and has played a prominent role in many scientific advances, from the Manhattan Project and the discovery of 16 chemical elements to breakthroughs in computer science and genomics. Berkeley is ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

William Wallace Campbell
William Wallace Campbell (April 11, 1862 – June 14, 1938) was an American astronomer, and director of Lick Observatory from 1901 to 1930. He specialized in spectroscopy. He was the tenth president of the University of California from 1923 to 1930. Biography He was born on a farm in Hancock County, Ohio, the son of Robert Wilson and Harriet Welsh Campbell. After a few years of local schooling he entered in 1882 the University of Michigan to study civil engineering, graduating Bachelor of Science in 1886. Whilst at university he developed his interest in astronomy when he read Simon Newcomb's ''Popular Astronomy''. After graduating he was appointed Professor of Mathematics at the University of Colorado but soon moved back to Michigan as an instructor in astronomy. In 1891 he was invited to work on spectroscopy at Lick Observatory in California. Campbell was a pioneer of astronomical spectroscopy and catalogued the radial velocities of stars. He was also recognized for his work ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Spectral Line
A spectral line is a dark or bright line in an otherwise uniform and continuous spectrum, resulting from emission or absorption of light in a narrow frequency range, compared with the nearby frequencies. Spectral lines are often used to identify atoms and molecules. These "fingerprints" can be compared to the previously collected ones of atoms and molecules, and are thus used to identify the atomic and molecular components of stars and planets, which would otherwise be impossible. Types of line spectra Spectral lines are the result of interaction between a quantum system (usually atoms, but sometimes molecules or atomic nuclei) and a single photon. When a photon has about the right amount of energy (which is connected to its frequency) to allow a change in the energy state of the system (in the case of an atom this is usually an electron changing orbitals), the photon is absorbed. Then the energy will be spontaneously re-emitted, either as one photon at the same frequenc ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Diffuse Interstellar Bands
Diffuse interstellar bands (DIBs) are absorption features seen in the spectra of astronomical objects in the Milky Way and other galaxies. They are caused by the absorption of light by the interstellar medium. Circa 500 bands have now been seen, in ultraviolet, visible and infrared wavelengths. The origin of most DIBs remains unknown, with common suggestions being polycyclic aromatic hydrocarbons and other large carbon-bearing molecules. Only one DIB carrier has been identified: ionised buckminsterfullerene (C60+), which is responsible for several DIBs in the near-infrared. The carriers of most DIBs remain unidentified. Discovery and history Much astronomical work relies on the study of spectra - the light from astronomical objects dispersed using a prism or, more usually, a diffraction grating. A typical stellar spectrum will consist of a continuum, containing absorption lines, each of which is attributed to a particular atomic energy level transition in the atmosphere ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing military alliances: the Allies and the Axis powers. World War II was a total war that directly involved more than 100 million personnel from more than 30 countries. The major participants in the war threw their entire economic, industrial, and scientific capabilities behind the war effort, blurring the distinction between civilian and military resources. Aircraft played a major role in the conflict, enabling the strategic bombing of population centres and deploying the only two nuclear weapons ever used in war. World War II was by far the deadliest conflict in human history; it resulted in 70 to 85 million fatalities, mostly among civilians. Tens of millions died due to genocides (including the Holocaust), starvation, ma ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Myocardial Infarction
A myocardial infarction (MI), commonly known as a heart attack, occurs when blood flow decreases or stops to the coronary artery of the heart, causing damage to the heart muscle. The most common symptom is chest pain or discomfort which may travel into the shoulder, arm, back, neck or jaw. Often it occurs in the center or left side of the chest and lasts for more than a few minutes. The discomfort may occasionally feel like heartburn. Other symptoms may include shortness of breath, nausea, feeling faint, a cold sweat or feeling tired. About 30% of people have atypical symptoms. Women more often present without chest pain and instead have neck pain, arm pain or feel tired. Among those over 75 years old, about 5% have had an MI with little or no history of symptoms. An MI may cause heart failure, an irregular heartbeat, cardiogenic shock or cardiac arrest. Most MIs occur due to coronary artery disease. Risk factors include high blood pressure, smoking, diabetes, ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Scotts Valley, California
Scotts Valley is a small city in Santa Cruz County, California, United States, about thirty miles (48 km) south of downtown San Jose and six miles (10 km) north of the city of Santa Cruz, in the upland slope of the Santa Cruz Mountains. As of the 2020 census, the city population was 12,224. Principal access to the city is supplied by State Route 17 that connects San Jose and Santa Cruz. The city was incorporated in 1966. History Approximately ten thousand years ago there was a lake in the lowest elevation of Scotts Valley, and Paleo Indians lived near its shores. Archeological excavations of site CA-SCR-177 in 1983 and 1987 support dates for human settlement of this area as between 9,000 to 12,000 years before present (''YBP''). The lake later receded to form a peat bog. Later, around 2000 BC, Ohlone people occupied areas along the remaining creeks, spring and seep areas, along with permanent and seasonal drainages, and on flat ridges and terraces. Therefore, ar ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

1897 Births
Events January–March * January 2 – The International Alpha Omicron Pi sorority is founded, in New York City. * January 4 – A British force is ambushed by Chief Ologbosere, son-in-law of the ruler. This leads to a punitive expedition against Benin. * January 7 – A cyclone destroys Darwin, Australia. * January 8 – Lady Flora Shaw, future wife of Governor General Lord Lugard, officially proposes the name "Nigeria" in a newspaper contest, to be given to the British Niger Coast Protectorate. * January 22 – In this date's issue of the journal ''Engineering'', the word ''computer'' is first used to refer to a mechanical calculation device. * January 23 – Elva Zona Heaster is found dead in Greenbrier County, West Virginia. The resulting murder trial of her husband is perhaps the only capital case in United States history, where spectral evidence helps secure a conviction. * January 31 – The Czechoslovak Trade Union Association is f ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]