Loyal Blaine Aldrich was an American

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 astrophysicist and 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...

 of the Smithsonian Institution

Smithsonian Institution

The Smithsonian Institution is an educational and research institute and associated museum complex, administered and funded by the government of the United States and by funds from its endowment, contributions, and profits from its retail operations, concessions, licensing activities, and magazines...

. Upon graduation from the University of Wisconsin in 1907, Aldrich became a Smithsonian Astrophysical Observatory

Smithsonian Astrophysical Observatory

The Smithsonian Astrophysical Observatory is a research institute of the Smithsonian Institution headquartered in Cambridge, Massachusetts, where it is joined with the Harvard College Observatory to form the Harvard-Smithsonian Center for Astrophysics .-History:The SAO was founded in 1890 by...

 assistant to Charles Greeley Abbot

Charles Greeley Abbot

Charles Greeley Abbot was an American astrophysicist, astronomer and Secretary of the Smithsonian Institution. He was born in Wilton, New Hampshire.-Life:...

. The observatory conducted astrophysical research on solar radiation and the amount of energy from the sun that strikes the outer edge of the earth's atmosphere. Abbot became director of the observatory in 1907 and established solar observing stations in the United States, South America, and Africa to carry out research on solar radiation. Aldrich became director of the observatory from 1942 to 1955. Harvard University

Harvard University

Harvard University is a private Ivy League university located in Cambridge, Massachusetts, United States, established in 1636 by the Massachusetts legislature. Harvard is the oldest institution of higher learning in the United States and the first corporation chartered in the country...

 astronomy department chairman Fred Lawrence Whipple

Fred Lawrence Whipple

Fred Lawrence Whipple was an American astronomer, who worked at the Harvard College Observatory for over 70 years...

 became director of the observatory when Aldrich retired.

Family

Aldrich married Elizabeth Stanley (born 9 October 1896). Their son, Stanley Loyal Aldrich, assisted his father operating the observing station in the Chile

Chile

Chile ,officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far...

an Andes

Andes

The Andes is the world's longest continental mountain range. It is a continual range of highlands along the western coast of South America. This range is about long, about to wide , and of an average height of about .Along its length, the Andes is split into several ranges, which are separated...

 until returning to the United States in 1957 so his daughters might receive education at Windham, Maine

Windham, Maine

Windham is a town in Cumberland County, Maine, United States. The population was 17,001 at the 2010 census. It includes the villages of South Windham and North Windham...

, where he taught high school mathematics.

Studies

Aldrich assisted Abbott's mapping of the 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...

 solar spectrum

Spectrum

A spectrum is a condition that is not limited to a specific set of values but can vary infinitely within a continuum. The word saw its first scientific use within the field of optics to describe the rainbow of colors in visible light when separated using a prism; it has since been applied by...

 and carried out systematic studies of variation in solar radiation, its relation to the sunspot

Sunspot

Sunspots are temporary phenomena on the photosphere of the Sun that appear visibly as dark spots compared to surrounding regions. They are caused by intense magnetic activity, which inhibits convection by an effect comparable to the eddy current brake, forming areas of reduced surface temperature....

 cycle, and its effect on weather

Weather

Weather is the state of the atmosphere, to the degree that it is hot or cold, wet or dry, calm or stormy, clear or cloudy. Most weather phenomena occur in the troposphere, just below the stratosphere. Weather refers, generally, to day-to-day temperature and precipitation activity, whereas climate...

 variation. He also studied the nature of atmospheric

Earth's atmosphere

The atmosphere of Earth is a layer of gases surrounding the planet Earth that is retained by Earth's gravity. The atmosphere protects life on Earth by absorbing ultraviolet solar radiation, warming the surface through heat retention , and reducing temperature extremes between day and night...

 transmission and absorption and assisted Abbot perfecting various standardised instruments now widely used for measuring the sun

Sun

The Sun is the star at the center of the Solar System. It is almost perfectly spherical and consists of hot plasma interwoven with magnetic fields...

's heat.

Publications

• A study of the lead voltameter
  Voltameter
  A Voltameter is a scientific instrument used for measuring quantity of electricity. It should not be confused with a voltmeter which measures electric potential...
  
   (1907)
• Smithsonian pyrheliometry revised (1913 with Charles Greeley Abbot)
• New evidence on the intensity of solar radiation outside the atmosphere (1915 with Abbot & Frederick E. Fowle)
• The pyranometer
  Pyranometer
  A pyranometer is a type of actinometer used to measure broadband solar irradiance on a planar surface and is a sensor that is designed to measure the solar radiation flux density from a field of view of 180 degrees...
  
   : an instrument for measuring sky radiation (1916 with Abbot)
• On the use of the pyranometer (1916 with Abbot)
• On the distribution of radiation over the sun's disk and new evidences of the solar variability (1916 with Abbot & Fowle)
• The Smithsonian eclipse
  Eclipse
  An eclipse is an astronomical event that occurs when an astronomical object is temporarily obscured, either by passing into the shadow of another body or by having another body pass between it and the viewer...
  
   expedition of June 8, 1918 (1919)
• The reflecting power of cloud
  Cloud
  A cloud is a visible mass of liquid droplets or frozen crystals made of water and/or various chemicals suspended in the atmosphere above the surface of a planetary body. They are also known as aerosols. Clouds in Earth's atmosphere are studied in the cloud physics branch of meteorology...
  
  s (1919)
• The melikeron - an approximately black-body pyranometer (1922)
• The distribution of energy in the spectra of the sun and stars (1923 with Abbot & Fowle)
• A study of body radiation (1928)
• An improved water-flow pyrheliometer
  Pyrheliometer
  A pyrheliometer is an instrument for direct measurement of solar irradiance. Sunlight enters the instrument through awindow and is directed onto a thermopile which converts heat to an electrical signal that can be recorded. The signal voltage is converted via a formula to measure watts per square...
  
  and the standard scale of solar radiation (1932 with Abbot)
• Supplementary notes on body radiation (1932)
• The standard scale of solar radiation (1934 with Abbot)
• Smithsonian pyrheliometry and the Andean volcanic eruptions of April 1932 (1944)
• The solar constant and sunspot numbers (1945)
• Smithsonian pyrheliometry and the standard scale of solar radiation (1948 with Abbot)
• Energy spectra of some of the brighter stars (1948 with Abbot)
• The Abbot silver-disk pyrheliometer (1949)
• Note on Fowle's spectroscopic method for the determination of aqueous vapor in the atmosphere (1949)