## What does the H-R diagram show you?

The Hertzsprung-Russell diagram shows the relationship between a star’s temperature and its luminosity. It is also often called the H-R diagram or colour-magnitude diagram. The chart was created by Ejnar Hertzsprung and Henry Norris Russell in about 1910.

### What is an H-R diagram easy?

The Hertzsprung-Russell diagram is a graph of many stars. It shows the relation between stars’ luminosity (that is, how bright they are) and their temperature (how hot they are). These diagrams are not pictures or maps of the locations of the stars.

Which of these is not typically found on the H-R diagram?

Which of these is not typically found on the H-R Diagram? red dwarfs. Most H-R Diagrams exclude red dwarfs, although they exist. When they are included in the H-R Diagram they are found in the bottom-right corner.

Why are stars hot and bright?

A star is a huge glowing ball of hot gas. Deep inside its core, hydrogen atoms smash together, forming helium and releasing huge amounts of energy that heats the gas. This is called nuclear fusion, and it’s why a star shines. As the hot gas pushes outward, it opposes the inward pull of gravity.

## What are the 4 categories of the HR diagram?

H-R Diagram Exercise By comparing the radii of different stars you will then find out the reason behind the names of the four categories of stars: white dwarfs, main-sequence stars, giants and supergiants.

### What color is a cold star?

red
Key Concepts and Summary. Stars have different colors, which are indicators of temperature. The hottest stars tend to appear blue or blue-white, whereas the coolest stars are red.

How do HR diagrams work?

Hertzsprung-Russell diagram, also called H-R diagram, in astronomy, graph in which the absolute magnitudes (intrinsic brightness) of stars are plotted against their spectral types (temperatures).

Why are there no black holes on the H-R diagram?

Black holes, the end result from catastrophic collapses of the most massive stars, emit no light on their own and therefore have no absolute visual magnitude. Their surroundings may become visible if they accrete mass from a binary companion, but they still cannot be placed on an H-R diagram.

## What stars are cool and dim?

Stars which lie along the top right of the diagram are luminous and cool and are known as supergiants. Fainter, hotter stars – which appear at the bottom left of the diagram – are known as white dwarfs. Hot and bright stars are located at the top left of the diagram, and cool, dim stars at the bottom right.

### What determines the color of a star?

The surface temperature of a star determines the color of light it emits. Blue stars are hotter than yellow stars, which are hotter than red stars.

What color is sunlight?

white
The fact that you see all the fundamental colors present in a rainbow (which is sunlight split by mist) and no colors are missing is direct evidence that sunlight is white. The sun emits all colors of visible light, and in fact emits all frequencies of electromagnetic waves except gamma rays.

Which star is hottest?

blue hypergiant stars
But the hottest known stars in the Universe are the blue hypergiant stars. These are stars with more than 100 times the mass of the Sun. One of the best known examples is Eta Carinae, located about 7,500 light-years from the Sun.

## What are the 4 categories of the H-R diagram?

### Why H-R diagram is important?

HR diagrams are valuable because they reveal important information about the stars plotted on them. After constructing an HR diagram for a group of stars, an astronomer can make estimates of many important stellar properties including diameter, mass, age, and evolutionary state.

Where is supernova on HR diagram?

They fall to the left of the upper-left quadrant of the above HR diagram. Neutron stars. Neutron stars (exemplified by X Persei) are the collapsed cores of supergiants that have exploded as supernovae.

Where is Mira on the HR diagram?

The Mira instability strip on the H-R diagram is located in a region between mid-sized stars on the main sequence and the giant branch. Mira was the second variable star to be discovered, by David Fabricius in 1596 – 24 years after Tycho’s observation of a Type Ia supernova.

## How do you read a HR diagram?

Explaining the HR diagram. An HR diagram is a plot of stellar luminosity (energy output) on the vertical axis and stellar surface temperature on the horizonal axis.

• Main Sequence: A star’s middle age. So,what then is the Main Sequence?
• The rest of the HR diagram. What about those other collections of stars on the HR diagram?
• ### What does the HR diagram depict?

The Hertzsprung-Russell diagram , also referred to as the H-R Diagram, is a graph of stellar absolute magnitude or luminosity versus their spectral type or photosphere temperature. The H-R Diagram was created circa 1910 by Danish astronomer Ejnar Hertzsprung and American astronomer Henry Norris Russell .

What is the definition of HR diagram?

H-R diagram synonyms, H-R diagram pronunciation, H-R diagram translation, English dictionary definition of H-R diagram. n. A graph of the absolute magnitudes or luminosities of stars plotted against their surface temperatures or colors, used to classify stars by their…

How to use the HR diagram?

– slow version of animated HR diagram – fast version of animated HR diagram – step through evolution manually