What are the four main classes of stars on an HR diagram?
The Supergiants are cool stars, which are very large and very bright. They are located towards the top right of the graph. The Giants are cool stars, which are a little smaller and dimmer than the Supergiants. The White Dwarfs are very hot stars, which are small in size and relatively dim.
What is the relationship between temperature and star brightness?
A star’s brightness, or luminosity, depends on the star’s surface temperature and size. If two stars have the same surface temperature, the larger star will be more luminous. The Hertzsprung-Russell (H-R) diagram below is a scatter plot that shows the relative temperatures and luminosities of various stars.
Is the relationship of brightness to temperature for these stars puzzling or does it make sense?
Hot d.Is the relationship of brightness to temperature for these stars puzzling, or does it make sense? Explain. Either answer can be correct depending on your explanation. Yes it is puzzling that hotter doesn’t equal brighter.
Is our sun a main sequence star?
As millions of years pass, the core temperature of a protostar reaches a point at which nuclear fusion can begin. The star then begins the longest stage of its life, called the “main sequence.” Most stars in the galaxy, including our Sun, are categorized as main sequence.
Who discovered the relationship between star’s temperature and brightness?
Henry Norris Russell
Are hotter stars brighter?
Stars on the Main Sequence that are hotter than the Sun are also larger than the Sun. So hot blue stars are more luminous (and therefore appear higher in this diagram) for two reasons: they are hotter, and hot objects are more luminous than cool objects, but they are also larger.
Which star is the brightest white dwarf?
Sirius B
Did Hertzsprung and Russell work together?
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.
What is the Sun classified as on the Hertzsprung-Russell diagram?
The sun is classified as Main sequence and dwarf star on the Hertzsprung-Russell diagram. Basically, the main sequence dominates the HR diagram. It stretches from the upper left (hot, luminous stars) to the bottom right (cool, faint stars). The sun is simply one of the countless stars in the universe.
Which main sequence stars on the Hertzsprung-Russell HR diagram are the least massive?
stars on the main sequence are powered by hydrogen fusion, which takes place in their cores, and the main sequence is just a sequence of mass (faint red stars are the least massive – starting at around one-tenth that of the Sun – and bright blue ones the most – about 20 times).
What information can you read from HR diagram?
The Hertzsprung-Russell Diagram is a graphical tool that astronomers use to classify stars according to their luminosity, spectral type, color, temperature and evolutionary stage. Stars in the stable phase of hydrogen burning lie along the Main Sequence according to their mass.
What do all stars on the main sequence have in common?
Main sequence stars are characterised by the source of their energy. They are all undergoing fusion of hydrogen into helium within their cores. The rate at which they do this and the amount of fuel available depends upon the mass of the star.