astronomy

Hipparchus of Nicaea and the Precession of the Equinoxes

Hipparchus of Nicaea and the Precession of the Equinoxes

Hipparchus of Nicaea was a Greek astronomer, geographer, and mathematician in the second century BC. He is considered the founder of trigonometry but is most famous for his incidental discovery of precession of the equinoxes. His other reputed achievements include the discovery and measurement of Earth‘s precession, the compilation of the first comprehensive star catalog of the western world, and possibly the invention of the astrolabe, also of the armillary…
Karl Jansky and the Discovery of Cosmic Radio Waves

Karl Jansky and the Discovery of Cosmic Radio Waves

On October 22, 1905, American physicist and radio engineer Karl Guthe Jansky was born. In August 1931 Jansky first discovered radio waves emanating from the Milky Way. He is considered one of the founding figures of radio astronomy. Karl Jansky was born the third of six children in what was then the Territory of Oklahoma where his father, Cyril M. Jansky, the descendent of Czech immigrants, was Dean of the College…
Ejnar Hertzsprung and the Hertzsprung-Russell Diagram

Ejnar Hertzsprung and the Hertzsprung-Russell Diagram

On October 8, 1873, Danish chemist and astronomer Ejnar Hertzsprung was born. Together with Henry Norris Russell, Hertzsprung developed the Hertzsprung–Russell diagram, a scatter graph of stars showing the relationship between the stars‘ absolute magnitudes or luminosities versus their spectral classifications or effective temperatures, which has become fundamental to the study of stellar evolution. Ejnar Hertzsprung was probably not formally educated, but studied in technological colleges in Denmark and became a…
ALMA – the largest and most expensive ground-based astronomical project

ALMA – the largest and most expensive ground-based astronomical project

On October 3, 2011, first images produced by the Atacama Large Millimeter Array were released to the press. The Atacama Large Millimeter/submillimeter Array (ALMA) is an astronomical interferometer of radio telescopes in the Atacama desert of northern Chile. ALMA is currently the largest and most expensive ground-based astronomical project, costing between US$1.4 and 1.5 billion. ALMA is an interferometer, i.e. ,amy small radio telescopes working together as a single large…
Sir Martin Ryle and Radio Astronomy

Sir Martin Ryle and Radio Astronomy

On September 27, 1918, English radio astronomer and Nobel Laureate Sir Martin Ryle was born. Ryle developed revolutionary radio telescope systems and used them for accurate location and imaging of weak radio sources. He was Astronomer Royal from 1972 to 1982 and shared the Nobel Prize in Physics in 1974 with Antony Hewish, the first Nobel prize awarded in recognition of astronomical research. Martin Ryle was the son of Professor John Alfred Ryle…
The first Observation of Gravitational Waves

The first Observation of Gravitational Waves

On September 14, 2015, the LIGO Scientific Collaboration observed gravitational waves from a 410 megaparsec (1.3 billion light years) distant merger of two black holes. Previously, gravitational waves had only been inferred only indirectly, via their effect on the timing of pulsars in binary star systems. It was also the first observation of a binary black hole merger, demonstrating both the existence of binary stellar-mass black hole systens, and the…
Leonid Kulik and the Tunguska Event

Leonid Kulik and the Tunguska Event

On August 19, 1883, Russian mineralogist Leonid Alekseyevich Kulik was born. Kulik is noted for his research in meteorites. In 1927, Kulik conducted the first scientific expedition (for which records survive) to study the Tunguska meteor impact site, the largest impact event in recorded history, which had occurred on 30 June 1908.[1] Leonid Kulik was born in Tartu, Estonia, which was later to become part of the Soviet Union, and was…
Jerry R. Ehman and the Wow! Signal

Jerry R. Ehman and the Wow! Signal

On August 15, 1977, a strong narrowband radio signal was received by the Big Ear radio telescope of the Ohio State University, United States, then assigned to a SETI project. Astronomer Jerry R. Ehman discovered the signal a few days later, while reviewing the recorded data and was so impressed that he circled the reading on the computer printout and wrote the comment Wow! on its side. Jerry R. Ehman…
Helen Hogg and the Globular Clusters

Helen Hogg and the Globular Clusters

On August 1, 1905, American-Canadian astronomer Helen Battles Sawyer Hogg was born. Hogg is noted for pioneering research into globular clusters (stars with cyclical changes of brightness found within huge, dense conglomerations of stars located in the outer halo of the Milky Way galaxy) and variable stars. She was the first female president of several astronomical organizations and a notable woman of science in a time when many universities would…
The Gran Telescopio Canarias

The Gran Telescopio Canarias

On July 14, 2007, the Gran Telescopio Canarias saw first light, also known as the Great Canary Telescope (GTC), located at the Roque de los Muchachos Observatory on the island of La Palma, in the Canaries, Spain. With an aperture of 10.4m, as of 2015, it is the world’s largest single-aperture optical telescope. It has a segmented mirror, i.e. an array of smaller mirrors designed to act as segments of…
Relation Browser
Timeline
0 Recommended Articles:
0 Recommended Articles: