In the early 20th century, Danish astrophysicist Ejnar Hertzsprung and American astrophysicist Henry Norris Russell independently developed a graph now known as the Hertzsprung-Russell (H-R) diagram, which plots absolute brightness against spectral type. In this diagram, the brightest stars lie near the top of the diagram and the hottest stars lie to the left. On the H-R diagram, most of the stars, including the Sun, fall along a diagonal line that goes from the upper left to the lower right of the diagram. This line called the main sequence.The great majority of stars neighboring the Sun fall on the lower part of the H-R diagram's main sequence, and relatively few lie on the portion of the main sequence above the Sun. This means that most of the Sun's neighboring stars are both cooler and fainter (in absolute magnitude) than the Sun. A smaller population of brighter but cooler stars known as supergiants occupies the uppermost region of the diagram. Some stars, which are difficult to discover because they are so intrinsically faint, lie near the bottom of the H-R diagram. These faint stars are called white dwarfs.
Henry Norris Russell was a pioneering American astronomer known for his work in stellar evolution and classification. His development of the Hertzsprung-Russell diagram revolutionized our understanding of stars and their characteristics. Russell also played a key role in establishing the field of astrophysics as a distinct discipline within astronomy.
The concept of stellar evolution was significantly advanced by the work of astrophysicists such as Sir William Herschel in the 18th century, but it was further developed in the 20th century by scientists like Subrahmanyan Chandrasekhar, who studied the life cycles of stars and the processes leading to phenomena like supernovae and black holes. The Hertzsprung-Russell diagram, created by Ejnar Hertzsprung and Henry Norris Russell, also played a crucial role in understanding how stars evolve over time based on their luminosity and temperature. Overall, the discovery of stellar evolution is attributed to the contributions of many scientists over time.
Hertzsprung-Russell diagrams are also referred to by the abbreviation H-R diagram or HRD. The diagram was created circa 1910 by Ejnar Hertzsprung and Henry Norris Russell and represents a major step towards an understanding of stellar evolution or "the lives of stars".
Henry Horn, who played the character Apollo in the film "Apollo 13," was born on June 10, 1950.
The first American man in space was Alan Shepard. He made history on May 5, 1961, when he piloted the Freedom 7 spacecraft during the Mercury-Redstone 3 mission. Shepard's flight lasted only 15 minutes, but it paved the way for future American space exploration.
The Hertzsprung-Russell diagram was created - as the name suggests - by Ejnar Hertzsprung and Henry Norris Russell in 1910
This plot is commonly referred to as a Hertzsprung-Russell (H-R) diagram, named after the astronomers Ejnar Hertzsprung and Henry Norris Russell who independently developed it in the early 20th century.
Ejnar Hertzsprung and Henry Norris Russell,working independently, realized the relationship between a star's temperature and its brightness.Together, in 1910, they formed what is now known as the Hertzsprung--Russell diagram or HR Diagram.It's a scatter graph showing the relationship between a star's absolute magnitudes, their spectral types and temperatures.
Henry Norris Russell died on 1957-02-18.
Henry Norris Russell was born on 1877-10-25.
The diagram was created by Ejnar Hertzsprung and Henry Norris Russell aound 1910.
Ejnar Hertzsprung and Henry Russell H for Hertzsprung and R for Russell
The relationship between a star's temperature and brightness was discovered independently around 1910 by Ejnar Hertzsprung and Henry Norris Russell. The relationship between these to parameters is depicted in a Hertzsprung-Russell diagram or H-R diagram.
The Hertzsprung-Russell diagram, or H-R diagram, was created in 1911 by Ejnar Hertzsprung and Henry Norris Russell. They plotted the luminosity of stars against their surface temperature to classify and study stellar populations. This diagram revolutionized our understanding of stars and their life cycles.
The two people who discovered the relationship between a star's temperature and its brightness were Ejnar Hertzsrung and H.N. Russell. The two men were working from research that had been done by Ludwig Boltzmann and Joseph Stefan.
Henry Norris Russell died on February 18, 1957 in Princeton, New Jersey from a heart attack. He was 79 years old at the time of his death. Russell was a renowned American astronomer known for his work in stellar classification and the Hertzsprung-Russell diagram.
Ejnar Hertzsprung and Henry Norris Russell,working independently, realized the relationship between a star's temperature and its brightness.Together, in 1910, they formed what is now known as the Hertzsprung--Russell diagram or HR Diagram.It's a scatter graph showing the relationship between a star's absolute magnitudes, their spectral types and temperatures.