Stellar Evolution Task Low Mass Stars How do they evolve

The evolutionary path of a low mass star Starter Task A The evolutionary path of a low mass star NEXT 100 000 Sun main sequence Hand out Luminosity 1 Sun Sun white dwarf 0.001 Sun 40 000 K 2 500 K Surface Temperature Draw the path from main sequence to white dwarf in the HR diagram provided on the printed hand-outs

What sizes can stars have Starter Task B What sizes can stars have NEXT Jupiter Sun Atom You NTU Nottingham Earth 0.000000000001 km 0.002 km 1 km 10 km 6 000 km 70 000 km 700 000 km Earth's Orbit Saturn's Orbit Solar System Next Star Sun Galaxy 40 000 000 000 000 km 300 000 000 000 000 000 km 700 000 km 150 000 000 km 1 500 000 000 km 6 000 000 000 km Hand out Highlight the smallest and largest sizes of a low mass star during its evolution on the size scale on the printed hand-out

Main page of low mass evolution Redo the starter tasks to finish Learn more about Luminosity Surface Temperature main sequence white dwarf 40 000 K 2 500 K 1 Sun 100 000 Sun 0.001 Sun Evolutionary Speed Size Evolution Colour Change Some Questions on low mass evolution Some further images and information on evolutionary stages

The evolutionary path of a low mass star Starter Task A The evolutionary path of a low mass star NEXT 100 000 Sun main sequence Hand out Luminosity 1 Sun Sun white dwarf 0.001 Sun 40 000 K 2 500 K Surface Temperature Draw the path from main sequence to white dwarf in the HR diagram provided on the printed hand-outs

What sizes can stars have Starter Task B What sizes can stars have NEXT Jupiter Sun Atom You NTU Nottingham Earth 0.000000000001 nm 0.002 km 1 km 10 km 6 000 km 70 000 km 700 000 km Earth's Orbit Saturn's Orbit Solar System Next Star Sun Galaxy 40 000 000 000 000 km 300 000 000 000 000 000 km 700 000 km 150 000 000 km 150 000 000 km 1 500 000 000 km Hand out Highlight the smallest and largest sizes of a low mass star during its evolution on the size scale on the printed hand-out

That's all on low mass stellar evolution ! Stellar Evolution Task That's all on low mass stellar evolution !

A low mass star in the HR diagram Time Luminosity Surface Temperature main sequence white dwarf 40 000 K 2 500 K 1 Sun 100 000 Sun 0.001 Sun Main sequence NEXT Play

A low mass star in the HR diagram Time Luminosity Surface Temperature main sequence white dwarf 40 000 K 2 500 K 1 Sun 100 000 Sun 0.001 Sun Subgiant branch Previous NEXT Play

A low mass star in the HR diagram Time Luminosity Surface Temperature main sequence white dwarf 40 000 K 2 500 K 1 Sun 100 000 Sun 0.001 Sun Red Giant Branch Previous NEXT Play

A low mass star in the HR diagram Time Luminosity Surface Temperature main sequence white dwarf 40 000 K 2 500 K 1 Sun 100 000 Sun 0.001 Sun Helium Flash Previous NEXT Play

A low mass star in the HR diagram Time Luminosity Surface Temperature main sequence white dwarf 40 000 K 2 500 K 1 Sun 100 000 Sun 0.001 Sun Horizontal Branch Previous NEXT Play

A low mass star in the HR diagram Time Luminosity Surface Temperature main sequence white dwarf 40 000 K 2 500 K 1 Sun 100 000 Sun 0.001 Sun Asymptotic Giant Branch Previous NEXT Play

A low mass star in the HR diagram Time Luminosity Surface Temperature main sequence white dwarf 40 000 K 2 500 K 1 Sun 100 000 Sun 0.001 Sun Planetary Nebula Previous NEXT Play

A low mass star in the HR diagram Time Luminosity Surface Temperature main sequence white dwarf 40 000 K 2 500 K 1 Sun 100 000 Sun 0.001 Sun Previous Return to Main Page Play

A low mass star in the HR diagram Luminosity Surface Temperature main sequence white dwarf 40 000 K 2 500 K 1 Sun 100 000 Sun 0.001 Sun Size Main sequence NEXT Play

A low mass star in the HR diagram Luminosity Surface Temperature main sequence white dwarf 40 000 K 2 500 K 1 Sun 100 000 Sun 0.001 Sun Size Subgiant branch Previous NEXT Play

A low mass star in the HR diagram Luminosity Surface Temperature main sequence white dwarf 40 000 K 2 500 K 1 Sun 100 000 Sun 0.001 Sun Red Giant Branch Size Previous NEXT Play

A low mass star in the HR diagram Luminosity Surface Temperature main sequence white dwarf 40 000 K 2 500 K 1 Sun 100 000 Sun 0.001 Sun Size Helium Flash Previous NEXT Play

A low mass star in the HR diagram Luminosity Surface Temperature main sequence white dwarf 40 000 K 2 500 K 1 Sun 100 000 Sun 0.001 Sun Size Horizontal Branch Previous NEXT Play

A low mass star in the HR diagram Luminosity Surface Temperature main sequence white dwarf 40 000 K 2 500 K 1 Sun 100 000 Sun 0.001 Sun Size Asymptotic Giant Branch Previous NEXT Play

A low mass star in the HR diagram Size Luminosity Surface Temperature main sequence white dwarf 40 000 K 2 500 K 1 Sun 100 000 Sun 0.001 Sun Planetary Nebula Previous NEXT Play

A low mass star in the HR diagram Luminosity Surface Temperature main sequence white dwarf 40 000 K 2 500 K 1 Sun 100 000 Sun 0.001 Sun Size Previous Return to Main Page Play

A low mass star in the HR diagram Luminosity Surface Temperature main sequence white dwarf 40 000 K 2 500 K 1 Sun 100 000 Sun 0.001 Sun Colour Main sequence NEXT Play

A low mass star in the HR diagram Luminosity Surface Temperature main sequence white dwarf 40 000 K 2 500 K 1 Sun 100 000 Sun 0.001 Sun Colour Subgiant branch Previous NEXT Play

A low mass star in the HR diagram Luminosity Surface Temperature main sequence white dwarf 40 000 K 2 500 K 1 Sun 100 000 Sun 0.001 Sun Red Giant Branch Colour Previous NEXT Play

A low mass star in the HR diagram Luminosity Surface Temperature main sequence white dwarf 40 000 K 2 500 K 1 Sun 100 000 Sun 0.001 Sun Helium Flash Colour Previous NEXT Play

A low mass star in the HR diagram Luminosity Surface Temperature main sequence white dwarf 40 000 K 2 500 K 1 Sun 100 000 Sun 0.001 Sun Horizontal Branch Colour Previous NEXT Play

A low mass star in the HR diagram Luminosity Surface Temperature main sequence white dwarf 40 000 K 2 500 K 1 Sun 100 000 Sun 0.001 Sun Asymptotic Giant Branch Colour Previous NEXT Play

A low mass star in the HR diagram Luminosity Surface Temperature main sequence white dwarf 40 000 K 2 500 K 1 Sun 100 000 Sun 0.001 Sun Planetary Nebula Colour Previous NEXT Play

A low mass star in the HR diagram Luminosity Surface Temperature main sequence white dwarf 40 000 K 2 500 K 1 Sun 100 000 Sun 0.001 Sun Colour Previous Return to Main Page Play

Stellar evolution low mass stars quiz Luminosity Surface Temperature main sequence white dwarf 40 000 K 2 500 K 1 Sun 100 000 Sun 0.001 Sun When has a low mass star reached its largest size? Click on the right region in HR diagram! Return to Main Page Next question

Stellar evolution low mass stars quiz When has a low mass star reached its largest size? Correct! On the Asymptotic Giant Branch a low mass star has reached its largest size of ~100 times larger than our Sun. Next question Return to Main Page

Stellar evolution low mass stars quiz When has a low mass star reached its largest size? Wrong! Either try again or have another look at the size evolution slides Redo question Return to Main Page

Stellar evolution low mass stars quiz Luminosity Surface Temperature main sequence white dwarf 40 000 K 2 500 K 1 Sun 100 000 Sun 0.001 Sun Which are the three longest evolutionary stages of a low mass star? Click on the one of the right regions in HR diagram! Previous question Next question Return to Main Page

Stellar evolution low mass stars quiz Which are the three longest evolutionary stages of a low mass star? Correct! The main sequence is the longest evolutionary phase of a low mass star. Our Sun remains for 4.5billion years a main sequence star. Try to find the other phases or go to the next question. Redo question Next question Return to Main Page

Stellar evolution low mass stars quiz Which are the three longest evolutionary stages of a low mass star? Correct! The horizontal branch is the third longest evolutionary phase of a low mass star. Try to find the other phases or go to the next question. Redo question Next question Return to Main Page

Stellar evolution low mass stars quiz Which are the three longest evolutionary stages of a low mass star? Correct! The white dwarf phase is the second longest evolutionary phase of a low mass star. Actually this isn't a real phase. It is more the like the grave of a low mass star. Try to find the other phases or go to the next question. Redo question Return to Main Page

Stellar evolution low mass stars quiz Which are the three longest evolutionary stages of a low mass star? Wrong! Either try again or have another look at the evolutionary speed slides. Redo question Return to Main Page

Stellar evolution low mass stars quiz Which colour does a giant in the evolution of a low mass star have before it becomes a planetary nebula? Click on the right colour! Luminosity Surface Temperature main sequence white dwarf 40 000 K 2 500 K 1 Sun 100 000 Sun 0.001 Sun Previous question Return to Main Page

Stellar evolution low mass stars quiz Which colour does a giant in the evolution of a low mass star have before it becomes a planetary nebula? Correct! These stars are very red since they are very cool. Our Sun will become as cold as 2 500 K on its surface. Return to Main Page

Stellar evolution low mass stars quiz Which colour does a giant in the evolution of a low mass star have before it becomes a planetary nebula? Wrong! Either try again or have another look at the colour change slides. Redo question Return to Main Page

Info on low mass evolution Main Page Click on an evolutionary phase in the HR diagram you want to learn more about! Red Giants Horizontal Branch Planetary Nebula 100 000 Sun Luminosity 1 Sun 0.001 Sun White Dwarfs 40 000 K 2 500 K Surface Temperature

Red Giants Betelgeuse Mira Info Page NEXT Red giants are sooo large that we can actually 'see' their size. Sadly we have to use very special techniques and can't just look through a very large telescope. Many bright red stars we see in the sky are red giants.

Red Giants NGC 6888 - Crecent Nebula Previous Info Page NEXT Red giants lose some of their mass during their evolution. This material can form beautiful nebula around them and also enriches the surrounding space with heavy elements.

An artists impression of a Red Giants Info Page An artists impression of a Supernova Type Ia The Red Giant on the right is in a double star system. It provides material for a white dwarf on the left. If the white dwarf collects enough material it will explode as a Supernova (Type Ia). Since this happens at a very specific mass and the brightness depends on the mass, we can use these special Supernova to derive distances to very distant galaxies.

A HR diagram of a cluster of old stars Horizontal Branch Info Page NEXT A HR diagram of a cluster of old stars In this figure it becomes clear why these stars are called horizontal stars: The location of all horizontal branch stars is highlighted and they all lie in a horizontal region.

Variable Horizontal branch stars Previous Info Page Variable Horizontal branch stars You will have noticed that some horizontal branch stars seemed to be above the normal region favoured by the others. These special stars are variable stars. Maybe you can spot them in the image of an old stellar cluster. These special stars are used to determine distance in our Galaxy.

Planetary Nebula M57 - Ring nebula Info Page NEXT During the Planetary Nebula phase the star becomes a white dwarf and ejects all its mass into space. What remains is a white dwarf in the centre and a beautiful symetric nebula. It looks like a ring since the mass the star has lost is in a spherical shell around it.

Planetary Nebula NGC 6543 Previous Info Page NEXT Sometimes the mass ejected by the star interacts with the mass it has lost during the Red Giant Phase and creates more complicated patterns. Here the nebula actually consists of two sperical shells. one to the top left and one to the bottom right of the star.

Planetary Nebula Previous Info Page In some cases the two spherical shells look as if they are open at each end.

White dwarfs in an old stellar cluster Info Page NEXT White dwarfs in an old stellar cluster White dwarfs are difficulat to observe since they are the faintest phase in the low mass stars evolution. However you will end up with loads of them after a while in an old cluster.

An artists impression of a White Dwarfs Previous Info Page An artists impression of a Supernova Type Ia The Red Giant on the right is in a double star system. It provides material for a white dwarf on the left. If the white dwarf collects enough material it will explode as a Supernova (Type Ia). Since this happens at a very specific mass and the brightness depends on the mass, we can use these special Supernova to derive distances to very distant galaxies.