Anders Jonas Angstrom



Anders Jonas Angstrom was raised in Sweden where he attended the University of Uppsala. It was there that in 1839 he became the private docent of physics. Then he moved on to the Uppsala Observatory where a year later he became the observer. During that time he became interested in terrestrial magnetism. He worked analyzing the magnetic data a Swedish frigate. He also succeeded the former chair of physics at Uppsala before he died in 1874. [1]




Insight and Infulences


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image courtesy of NNDB
Anders Jonas Angstrom was born into a wealthy, upper class family in Logodo, Sweeden in 1814 during a solar eclipse. He whent to the University of Uppsala where he studied physics and astronomy and eventually became the privat doccent of physics. He also got his doctorate at the Univeristy of Uppsala in 1839. Anders had a better chance at a education and a good life because he was born into the clergy, which is what the uppper class was called in Europe. Back then your social class made all the difference so him being in the clergy which is the highest and has connections with the church gives him the advantages and opportunities.

Also in 1839 he became a professor at Uppsala Univeristy and got his own observatory. Since he was first to discover hydrogen in our atmoshphere he got to study the aurora borealis also known as the northern lights, which was a bright line in the yellow green region, at his observatory. He then was able to diprove the hypothesis about the Northern Lights that said that they were caused by sunlight being reflected through airborne ice crystals and proved that it was excited oxogen atoms. The oxogen atoms emitted the light because they were "super charged" by then sun in a way which made them produce color. He also invented an instument that became standard in 1905 for measuring solar radiation. With this knowledge he also helped invent spectroscopy which is the study of spectra.

His most known work was on Optiska Undersökningar. Optsika was one of his optical studies. It dealt mainly with electrical sparks and the two spectras that it produced. In this he also determined that gas emits light at the same wavelength that it takes it in. He also worked in thermal studies. He invented a way to measure the temperature consitering its electrical conductivity. He also studied geomagnitism which is also known as terestial magnitism which is the magnitism of the earth. Most all of his work dealt with spectrums which he was first to discover a lot about in many different fields of it such as solar, and atomic spectrums. Despite how realevant his work was, he was never honored even in his own country or abroad. He was honored more at the university than in the scienfic community. A reward at the University of Uppsala was, for example, recieving the chair of physics. Though he did get rewarded Secretary of the Royal Society of Science in Uppsala and other organization. His name was used as a name for a unit, the Angstrom, but was officially changed to the micrometer. [2]



Major Contributions



Anders Jonas Angstrom contributed many things to physics. He was first to do a few thing and invented stuff that scientists and spectroscopes’ still use today. One of which being spectroscopy. Spectroscopy is the study of spectra’s. Almost all of his work dealt with spectra’s. An example of a spectrum is the Aurora Borealis or is the Northern Lights which he was the first to analyze using a prism. He was able to disprove the accepted theory that the northern lights came from sun reflecting off of airborne ice crystals and prove that it was exited oxygen atoms. They were considered "exited because they were charged from the sun which made them produce colors in the sky. He is also known for working on the atomic and solar spectra’s. In the atomic spectra his major work was with the Optical Investigations in 1853 where he wrote about measurements of electric sparks. With this he was able to show that gas produces light at about the same wavelength that it absorbs it. So with his principles of spectroscopy he moved on to the solar spectra. In his research of the solar spectra he was able to find that the sun had hydrogen in it. While doing this he found Fraunhofer lines that had six significant did gets. They used his name, Angstrom, as the name for this measurement.

As I talked about in the previous paragraph, they used the name Angstrom as a measurement. The angstrom is more commonly known as the micrometer. The micrometer is still used to day in spectroscopy. The micrometer is 10–6 of a meter, or one-millionth of a meter. For a comparison, a human hair is about 50 micrometers wide. Anders Jonas Angstrom used this measurement to measure more than 1000 spectral lines in the Solar Spectra. It is still used today even though it is not a standard SI unit. The measurement is commonly used to measure wavelengths of light and size determination in microscopy. The angstrom is also used to describe atomic dimensions and molecular dimensions.

In Angstrom's study of the solar spectra and the spectra of hot gasses he found relationships in the Fraunhofer lines. To measure this he invented the pyrheliometer which was designed to show the instantaneous amount of incident solar radiation. That means that it
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image courtesy of meteor
measures the duration of time that the surface of the earth receives sunlight and how intense the sunlight actually is as well. The instrument contains a receiver that takes in and absorbs the sun's rays near the focus of a convex lens, where the flux, or the rate of flow of energy or particles across a given surface, is concentrated. The irradiated receiver area is isothermal which makes it able to be small and head conductive so you only need one because it is distinctive enough to not get mixed with the other surrounding temperature. The flux is then calculated by substituting the recorded temperature difference into a "linear experiment calibration chart" or into a "linear characteristic formula" that was derived analytically. [3]





Affects and Effects


Anders Jonas Angstrom effected many people in his region of the world and studies. One thing such as the pyrheliometer. Scientists that study direct solar radiation today still use the pyrheliometer to measure the fraunhofer lines. Though his largest affect on someone was probably on his grandson who followed in his footsteps with studying spectras.

Dr. Anders Angstrom, named after his grandfather Anders Jonas Angstrom, was the 3rd generation in his family to work with atmospheric physics and atmospheric radiation. Dr. Angstrom started to work with his father at the University of Uppsala. Working there he got to do many observations, handle instruments, do outdoor work and tag along on expeditions. After his father died he went to work with C. G. Abbot in Algeria. At his time Angstrom was 24 years old. Together they were able to do many great calibrations. Angstrom was delighted to finnaly be able to use his grandfathers solar radiation equipment. After that expediton he traveled back to the U.S.A. with the Abbot family to continue his studies. Angstrom, while at Cornell University, met
Dr. E. Kennard and went on an expedition with him to Mount Whitney. They made the expedition to Mt. Whitney so that Angstrom could use his father's pyrgeomter to measure outgoing long-wave radiation. There on Mt. Whitney he conducted calculations of carbon dioxide on radiation in the atmosphere which had been neglected for many years.

Anders received his doctorate in 1916 at the University of Uppsala. He worked there for the next 2 years as the associate professor. Afterwards he joined the Swedish Meteorological and Hydrological Institute and quickly began studying the relationship between solar radiation and climatology. Some of the methods he invented for calculating global radiation from sunlight are still used today. Eventually he became the director of the institute before he retired 6 years later in 1955. Though he still continued regular studies at the Eppley laboratory until 1965. Although his main field of study was energy exchange and solar radiation, he wrote 151 or more scientific papers on climatology. He also developed ways to predict frost and even forest fires from his studies. Angstrom's contributions to the scientific community did not come unnoticed. He received many rewards such as becoming a member of the Swedish Forestry and Agricultural Academy, being made a member of the Swedish Military Science Academy, and elected into the Swedish Royal Academy of Science. Also he was given the IMO price internationally. Dr. Angstrom was a very polite, friendly, humorous and of course intelligent man. Throughout his long life he retained all of these qualities. He, like his father and grandfather, made his fair share of contributions to the field of solar radiation.

All the success that Dr. Angstrom had all came from his father and mainly his grandfather, Anders Jonas Angstrom. Anders Jonas Angstrom was the first of his family to be a physicist and was not the last. His son and grandson followed in his footsteps making major contributions to the scientific community, specifically spectras and solar radiation, and also climatology. [4]




The Things they Left Behind


Anders Jonas Angstrom contiributed many things to the scienficic community and left a legacy in his son and grandson. They pyrheliometer that he invented that measures solar radiation is still used today. Also he invented the micrometer which was named the angstrom when he invented it. The micrometer is still a standard SI unit today when measuring the small lines in spectra's. Anders Jonas Angstrom made many contriubutions to the scientific field involved with spectras. He was the first to examine the Northern Lights and figure out why they actually show up as colors. Anders Jonas Angstrom was also the start of a 3 generation long chain of scientists that contribute to the area of specra's. His son and grandson both contriubted much to the scientific field of spectra's. His son, Knut Angstrom, was known for the research that he did while at the University of Uppsala. Also, Knut was known for making his father's invention, the pyrheliometer, electronic. Knut's son, Dr. Anders Angstrom, named after his grandfather, used his father's and grandfather's inventions and tools to do field work. All three of them received many awards, though mainly just in Sweden but none the less, they were recognized for their major contributions in the field of spectra's. Even though Anders Jonas Angstrom died in 1874 his work, in a way, carried on for almost another century through his son and grandson.



References



1. The introduction http://www.nndb.com/people/929/000100629/
2. Insights and influences http://micro.magnet.fsu.edu/optics/timeline/people/angstrom.html /http://www.pa.msu.edu/sciencet/ask_st/112697.html/http://www.answers.com/topic/anders-jonas-ngstrom
3. Major Contributions http://www.astro.uu.se/history/angstrom.html / http://micro.magnet.fsu.edu/optics/timeline/people/angstrom.html / http://www.todayinsci.com/8/8_13.htm / http://whatis.techtarget.com/definition/0,,sid9_gci866387,00.html / http://www.britannica.com/EBchecked/topic/484874/pyrheliometer / http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JSEEDO000126000003000915000001&idtype=cvips&gifs=yes
4. Affects and Effects http://www.wmo.int/pages/publications/bulletin_en/interviews/angstrom_en.html

5. Pictures http://www.nndb.com/people/929/000100629/ / http://www.meteor.gov.tr/genel/meteorolojikaletler.aspx?a=j