What 4 groups of stars can be located on the HR diagram?

The group called the main sequence extends in a rough diagonal from the upper left of the diagram (hot, bright stars) to the lower right (dim and cool). Large, bright, though cool, stars called giants and supergiants appear in the upper right, and the white dwarfs, dim, small, and hot, lie in the lower left.

What are the 4 groups on 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 are the 4 things we can determine about stars using an HR diagram?

They can also reveal information about its temperature, motion through space, and its magnetic field strength. By plotting the stars on the H-R diagram according to their temperatures, spectral classes, and luminosity, astronomers can classify stars into their different types.

How many major groups of stars can be found on the HR diagram?

four major groups

The H-R Diagram plots stars such that there are four major groups. 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.

What stars does the HR diagram show?

The Hertzsprung–Russell diagram, abbreviated as H–R diagram, HR diagram or HRD, is a scatter plot of stars showing the relationship between the stars’ absolute magnitudes or luminosities versus their stellar classifications or effective temperatures.

What are the different group of stars?

The patterns of stars seen in the sky are usually called constellations, although more acurately, a group of stars that forms a pattern in the sky is called an asterism.

What are the five main groups of stars?

There are seven main types of stars. In order of decreasing temperature, O, B, A, F, G, K, and M. This is known as the Morgan–Keenan (MK) system. The majority of all stars in our galaxy and even the Universe are main-sequence stars.

What are the 3 main types of stars?

There are seven main types of stars. In order of decreasing temperature, O, B, A, F, G, K, and M. O and B are uncommon, very hot and bright. M stars are more common, cooler and dim.

What two main characteristics of stars does the HR diagram graph?

The Hertzsprung–Russell diagram, or H–R diagram, is a plot of stellar luminosity against surface temperature. Most stars lie on the main sequence, which extends diagonally across the H–R diagram from high temperature and high luminosity to low temperature and low luminosity.

Where is Betelgeuse located on the HR diagram?

constellation Orion

Betelgeuse in the constellation Orion — X-axis: 3000K, Y-axis 10 ⁵ M.

Which group of stars represents the main sequence How do you know this?

It shows a general trend from cool, dim stars in the lower right corner up to hot, extremely bright stars in the top left corner which fits in with our expected relationship between temperature and luminosity. This group is called the Main Sequence so stars found on it are main sequence stars.

Where do we find our star on the HR diagram?

Notice that the scales are not linear. Hot stars inhabit the left hand side of the diagram, cool stars the right hand side. Bright stars at the top, faint stars at the bottom. Our Sun is a fairly average star and sits near the middle.

What type of star on the HR diagram is the most common?

red dwarf

The most common type of star is the red dwarf (lower right); the least common type is the blue giant (upper left).

Where is Sirius A located on the HR diagram?

Sirius falls in the center of an H-R Diagram. In terms of size, Sirius is about average.

Where are the oldest stars on the HR diagram?

As time passes the most massive stars at the top of the main sequence evolve into red giants. Therefore, the older the cluster, the fewer stars to be found at the top of the main sequence, and an obvious grouping of red giants will be seen at the top right of the HR diagram.

Where are star clusters found?

More than 150 globular clusters were known in the Milky Way Galaxy by the early years of the 21st century. Most are widely scattered in galactic latitude, but about a third of them are concentrated around the galactic centre, as satellite systems in the rich Sagittarius-Scorpius star fields.

Why do stars form in groups?

The sinks (stars) tend to collect together into small groups or mini-clusters, because they tend to form together in regions of high density, and because they also tend to fall in toward each other as they accumulate mass.

Which star cluster is older?

A team of astronomers using the Gemini-South telescope has discovered one of the oldest stellar clusters in the Milky Way. The team’s results date the globular cluster, named HP 1, at about 12.8 billion years, making its stars among the oldest ever found in our Galaxy.

How is the HR diagram used to determine the age of a star cluster?

By placing the stars in a globular cluster on a Hertzprung-Russell diagram, astronomers can determine the cluster’s age by looking at the main sequence turnoff point and comparing it with models of stellar evolution.

What is the name of our star cluster?

Ask Astro: What happened to the Sun’s original star cluster? At the core of NGC 6357 sits the open cluster Pismis 24. Our own Sun was born within such a cluster 4.6 billion years ago. Since then, it and its stellar siblings have dispersed throughout the galaxy, but astronomers are keen to hunt those siblings down.

Which cluster is the youngest?

Deep Galileo (Telescopio Nazionale Galileo) B, V and I images of Segue 3, reaching V ∼ 25, reveal that it is the youngest globular cluster known so far in the Galaxy. A young age of 3.2 Gyr is found, differently from a previous estimate of 12 Gyr.

Where do spectral types appear on the HR diagram the spectral types in the order Obafgkm can be labeled?

Note that any star can be plotted on the H-R diagram if you know its surface temperature and luminosity. Also recall that the horizontal axis can be equivalently labeled with spectral type in the order OBAFGKM, because O stars are the hottest and M stars are the coolest.

Which is true for the HR diagram of a star cluster that has many hot blue luminous stars?

If a star cluster has many hot, blue, luminous stars which of the following is probably correct? It is young. The H-R diagram of a star cluster that has many hot, blue, luminous stars will have stars over most of the main sequence and be young in age.

Why do we not observe O and B stars in globular clusters?

Why are there no massive O or B stars in globular clusters? Globular clusters are very old and almost totally lacking in the gas and dust needed for new stars to form. Both O and B stars, which are the largest, require a lot of gas and dust to form.

What types of stars are in globular clusters?

Globular clusters are generally composed of hundreds of thousands of low-metal, old stars. The stars found in a globular cluster are similar to those in the bulge of a spiral galaxy but confined to a spheroid in which half the light is emitted within a radius of only a few to a few tens of parsecs.

How many stars do globular clusters contain?

Globular clusters are big. They can reach 300 light-years in diameter and contain 10 million stars.