Heinrich Schwabe
Encyclopedia
Samuel Heinrich Schwabe (25 October 1789 – 11 April 1875) a German
astronomer
remembered for his work on sunspot
s.
Schwabe was born at Dessau
. At first an apothecary
, he turned his attention to astronomy
, and in 1826 commenced his observations on sunspot
s. Schwabe was trying to discover a new planet
inside the orbit
of Mercury
which was tentatively called Vulcan
. Because of the proximity to the Sun
, it would have been very difficult to observe Vulcan, and Schwabe believed one possibility to detect the planet might be to see it as a dark spot when passing in front of the Sun. For 17 years, from 1826 to 1843, on every clear day, Schwabe would scan the sun and record its spots trying to detect Vulcan among them. He didn’t find the planet but noticed the regular variation in the number of sunspots and published his findings in a short article entitled "Solar Observations during 1843". In it he made the suggestion of a probable ten year period
(i.e. that at every tenth year the number of spots reached a maximum). This paper at first attracted little attention, but Rudolf Wolf
who was at that time the director of Bern observatory, was impressed so he began regular observations of sunspots. Schwabe's observations were afterwards utilized in 1851 by Alexander von Humboldt
in the third volume of his Kosmos
. The periodicity of sunspots is now fully recognized; and to Schwabe is thus due the credit of one of the most important discoveries in astronomy.
In 1857 Schwabe was awarded the Gold Medal of the Royal Astronomical Society
.
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
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...
remembered for his work on 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....
s.
Schwabe was born at Dessau
Dessau
Dessau is a town in Germany on the junction of the rivers Mulde and Elbe, in the Bundesland of Saxony-Anhalt. Since 1 July 2007, it is part of the merged town Dessau-Roßlau. Population of Dessau proper: 77,973 .-Geography:...
. At first an apothecary
Apothecary
Apothecary is a historical name for a medical professional who formulates and dispenses materia medica to physicians, surgeons and patients — a role now served by a pharmacist and some caregivers....
, he turned his attention to astronomy
Astronomy
Astronomy is a natural science that deals with the study of celestial objects and phenomena that originate outside the atmosphere of Earth...
, and in 1826 commenced his observations on 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....
s. Schwabe was trying to discover a new 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,...
inside the 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...
of Mercury
Mercury (planet)
Mercury is the innermost and smallest planet in the Solar System, orbiting the Sun once every 87.969 Earth days. The orbit of Mercury has the highest eccentricity of all the Solar System planets, and it has the smallest axial tilt. It completes three rotations about its axis for every two orbits...
which was tentatively called Vulcan
Vulcan (hypothetical planet)
Vulcan was a small planet proposed to exist in an orbit between Mercury and the Sun. In an attempt to explain peculiarities of Mercury's orbit, in the 19th-century French mathematician Urbain Jean Joseph Le Verrier hypothesized that they were the result of another planet, which he named Vulcan...
. Because of the proximity to 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...
, it would have been very difficult to observe Vulcan, and Schwabe believed one possibility to detect the planet might be to see it as a dark spot when passing in front of the Sun. For 17 years, from 1826 to 1843, on every clear day, Schwabe would scan the sun and record its spots trying to detect Vulcan among them. He didn’t find the planet but noticed the regular variation in the number of sunspots and published his findings in a short article entitled "Solar Observations during 1843". In it he made the suggestion of a probable ten year period
Frequency
Frequency is the number of occurrences of a repeating event per unit time. It is also referred to as temporal frequency.The period is the duration of one cycle in a repeating event, so the period is the reciprocal of the frequency...
(i.e. that at every tenth year the number of spots reached a maximum). This paper at first attracted little attention, but Rudolf Wolf
Rudolf Wolf
Johann Rudolf Wolf was a Swiss astronomer and mathematician best known for his research on sunspots.Wolf was born in Fällanden, near Zurich. He studied at the universities of Zurich, Vienna, and Berlin. Encke was one of his teachers. Wolf became professor of astronomy at the University of Bern in...
who was at that time the director of Bern observatory, was impressed so he began regular observations of sunspots. Schwabe's observations were afterwards utilized in 1851 by Alexander von Humboldt
Alexander von Humboldt
Friedrich Wilhelm Heinrich Alexander Freiherr von Humboldt was a German naturalist and explorer, and the younger brother of the Prussian minister, philosopher and linguist Wilhelm von Humboldt...
in the third volume of his Kosmos
Kosmos (Humboldt)
Kosmos was an influential treatise on science and nature written by the German scientist and explorer Alexander von Humboldt. Kosmos began as a lecture series delivered by Humboldt at the University of Berlin, and was published in five volumes between 1845 and 1862...
. The periodicity of sunspots is now fully recognized; and to Schwabe is thus due the credit of one of the most important discoveries in astronomy.
In 1857 Schwabe was awarded the Gold Medal of the Royal Astronomical Society
Gold Medal of the Royal Astronomical Society
-History:In the early years, more than one medal was often awarded in a year, but by 1833 only one medal was being awarded per year. This caused a problem when Neptune was discovered in 1846, because many felt an award should jointly be made to John Couch Adams and Urbain Le Verrier...
.
External links
- Excerpts from Solar Observations During 1843 by Heinrich Schwabe http://www.phy6.org/Education/whschwab.html.
- Address delivered by the President of the RAS on presenting the Gold Medal of the Society to M. Schwabe http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?1857MNRAS..17..126.
- HAO "S. Heinrich Schwabe (1789-1875)" http://www.hao.ucar.edu/Public/education/bios/schwabe.html
- HAO "S. Heinrich Schwabe (1789-1875)" http://web.hao.ucar.edu/public/education/sp/images/schwabe.html with portrait.
- Chris Plicht "Schwabe, Samuel Heinrich (1789 - 1875)" http://www.plicht.de/chris/32schwab.htm
- The Sun—History http://www-istp.gsfc.nasa.gov/Education/whsun.html