Ejnar Hertzsprung (, 8 October 1873 – 21 October 1967 ) was a Danish chemist and astronomer.

* Hertzsprung – Russell diagram – Relates absolute magnitude or luminosity versus spectral color or surface temperature.

These color-magnitude plots are known as Hertzsprung – Russell diagrams after their co-developers, Ejnar Hertzsprung and Henry Norris Russell.

In Potsdam in 1906, the Danish astronomer Ejnar Hertzsprung noticed that the reddest stars — classified as K and M in the Harvard scheme — could be divided into two distinct groups.

Of the red stars observed by Hertzsprung, the dwarf stars also followed the spectra-luminosity relationship discovered by Russell.

This name reflected the parallel development of this technique by both Hertzsprung and Russell earlier in the century.

The first color-magnitude diagrams of open clusters were published by Ejnar Hertzsprung in 1911, giving the plot for the Pleiades and Hyades star clusters.

A plot of the temperature of many stars against their luminosities, known as a Hertzsprung – Russell diagram ( H – R diagram ), allows the age and evolutionary state of a star to be determined.

A Hertzsprung – Russell Diagram can be plotted for these clusters which has absolute values known on the luminosity axis.

The PMS star follows a Hayashi track on the Hertzsprung – Russell ( H – R ) diagram.

Hertzsprung – Russell diagram identifying stellar luminosity as a function of temperature for many stars in our solar neighborhood. In astronomy, luminosity is the amount of electromagnetic energy a body radiates per unit of time.

He befriended fellow students Bart Bok and Pieter Oosterhoff and was taught by Ejnar Hertzsprung, Antonie Pannekoek, Willem de Sitter, Jan Woltjer, Jan Oort and the physicist Paul Ehrenfest.

Kuiper finished his doctoral thesis on binary stars with Hertzsprung in 1933, after which he immediately traveled to California to become a fellow under Robert Grant Aitken at the Lick Observatory.

Hertzsprung was born in Copenhagen.

In the period 1911 – 1913, together with Henry Norris Russell, he developed the Hertzsprung – Russell diagram.

From 1919 to 1946 Hertzsprung worked at Leiden Observatory in The Netherlands, from 1937 as director.

The so-called " Hertzsprung – Russell Diagram " has been used ever since as a classification system to explain stellar types and evolution.

In 1913, Ejnar Hertzsprung did some work on Cepheids, which needed some revision.

They occupy the top region of the Hertzsprung – Russell diagram.

Using this period-luminosity relation, in 1913 the distance to the SMC was first estimated by Ejnar Hertzsprung.

The various distinctive types of stars are shown by the Hertzsprung – Russell diagram ( H-R diagram ), which is a plot of absolute stellar luminosity versus surface temperature.

Standard theories of stellar evolution hold that the position of a star on the Hertzsprung – Russell diagram should be determined almost entirely by the initial mass of the star and its age.

On Good Friday 1158, bishop Asser of Roskilde died, and Absalon was eventually elected bishop of Roskilde on Zealand with the help of Valdemar, as the king's reward for the Hvide family support.

King Christian III died on New Year's Day 1559 at Koldinghus and was interred in Roskilde Cathedral.

She died on 25 November 1495, and is interred next to her second husband in Roskilde Cathedral.

It had similarities to both the more lethal events that happened at the Love Parade concert in Duisburg in North Rhine-Westphalia on 25 July 2010, in which 21 died and 340 were injured, and the Roskilde Festival accident in Denmark a few years earlier.

She died on 28 December 1952 in Copenhagen, and is interred next to her husband in Roskilde Cathedral.

When Bluetooth died in 985 / 986, the army that had been raised against him brought his body to Roskilde and buried him in the church he had built.

He died of pneumonia at the age of 84 at Westminster Hospital on 8 October 1967.

He died at his home in Gerrards Cross on December 4, 1967.

Blyton's husband died in 1967.

He died at Roosevelt Hospital in New York City on August 19, 1967.

He was sent to work in Jos, Nigeria by the bank in 1967, and he nearly died in a car accident there.

Adenauer died on 19 April 1967 in his family home at Rhöndorf.

Tatsu Yamada died in 1967, but his dojo changed its name to Suginami Gym, and kept sending kickboxers off to support kickboxing.

A story that ran for several weeks in the Sunday comics of Li ' l Abner during 1967 concerned the creation of a joke, never actually revealed, that was so funny that anyone who heard it immediately died laughing.

The opposition was extremely skeptical of Somoza's promises, and ultimately control of the country passed to Anastasio Somoza Debayle after Luis died of a heart attack in 1967.

Magritte died of pancreatic cancer on 15 August 1967 in his own bed, aged 68, and was interred in Schaerbeek Cemetery, Evere, Brussels.

* January 21 – Marcellus Boss, American politician and lawyer, member of Kansas Senate and 5th Civilian Governor of Guam ( died 1967 )

* April 18 – Al Lewis, American songwriter ( died 1967 )

* June 29 – Nelson Eddy, American singer and actor ( died 1967 )

Chaffee died along with fellow astronauts Gus Grissom and Ed White during a pre-launch test for the Apollo 1 mission at the then-Cape Kennedy Air Force Station, Florida, in 1967.

According to her obituary in Jet magazine, she was " omesick for Washington " and returned ( she died in 1967 ).

Zadkine died in Paris in 1967 at the age of 77 after undergoing abdominal surgery and was interred in the Cimetière du Montparnasse.

Muni died of a heart disorder in Montecito, California in 1967, aged 71.

He had five children by his first wife — Richard ( 1889 – 1968 ), Mair ( 1890 – 1907, who died during an appendectomy ), Olwen ( 1892 – 1990 ), Gwilym ( 1894 – 1967 ) and Megan ( 1902 – 1966 ) — and possibly one child by Stevenson, a girl named Jennifer ( 1929 – 2012 ).

After a long illness Dame Anne McEwen died on 10 February 1967.

Inside the Mausoleum itself are the remains of the last four sultans, Haji Sir Muda Omar Ali Saifuddin ( 1950 – 1967 ), who died in 1986, Ahmad Tajuddin Ibnu Sultan Muhammad Jamalul Alam ( 1924 – 1950 ), Muhammad Jamalul Alam Ibnu Sultan Hashim ( 1906 – 1924 ), and Hashim Jalilul Alam Putera Sultan Omar Ali Saifuddin II ( 1885 – 1906 ).

Rains died from an abdominal haemorrhage in Laconia, New Hampshire, on 30 May 1967 at the age of 77.

Danjon died in 1967 in Paris.

Hopper died in his studio near Washington Square in New York City on May 15, 1967.

His first wife died in October 1923, and in August of the next year Schoenberg married Gertrud Kolisch ( 1898 – 1967 ), sister of his pupil, the violinist Rudolf Kolisch ( Neighbour 2001 ; Silverman 2010, 223 ).

Yusupov died in Paris in 1967.