Neutron stars

They're the best kind of star!

By Lucas Gagnon and Jeremy Alfaro

Some facts...• Neutron stars are in the end stage of stellar

evolution.• They are formed by type II supernovas, from

stars that are from 8 to 20-30 solar masses, although a specific range is not fully known.

• Neutron stars have a mass of 1.4-3 solar masses(lower would be a white dwarf, higher would form a black hole)

• Because of the intense gravity, they are almost perfectly spherical

• Another effect of gravity is that

Neutron stars are so dense, that 1 teaspoon of Neutron star material would weigh 10 billion tons!

• Neutron stars are usually around 20km in diameter

• Because of this, they are very hard to observe in the sky.

• They would look very blue if we could see them

• This is a picture of a Neutron star. As you can see, it is very small in comparison to other stars in the picture.

How Neutron stars are made• After the type II supernova, gravity is so

strong it breaks atomic bonds, crushing the newly dead star's core into a clump of subatomic particles.

• The Protons and Electrons present are crushed together, resulting in Neutrons and Neutrinos, and the Neutrinos then shoot off into space, helping in making the supernova bigger.

The composition of Neutron stars

• Neutron stars are, of course made mostly of Neutrons, increasing in density as you progress inwards.

• Because of the Protons and Electrons being combined, Neutron stars are only 5-10% Protons and Electrons

• It is, as of now, unknown what the core is made of

Radio Pulsars

–Radio pulsars are spinning neutron stars that emit high energy matter from their magnetic poles(often quite different from the axis of rotation) at up to 1/5th the speed of light!

–After a really long time, they slow down

–They spin from once every 5 seconds to every 1.3 miliseconds

More about radio pulsars

• Because of the difference between the magnetic poles and the axis of rotation, the radio beams coming from the magnetic poles turn, like a lighthouse.

• We can only see the “Pulse” when the beam is pointing directly towards earth, so it appears to turn on and off

X ray pulsars

–X ray pulsars are Neutron stars with a companion star. The Neutron star's gravity sucks away gas from its companion. The gas is then pulled into a disk rotating around the neutron star. It super heats as it approaches the Neutron star's magnetic field, and gives off X rays–The gas speeds up the Neutron star. This is believed to be the origin of milisecond pulsars

• This is an artist's image of an X ray pulsar.• You can see gas being taken from the companion star and rotating

around the Neutron star(the white spot in the middle of the disk)

• Questions?

• Image: an artists rendition of a Neutron star flare up that was observed in 2004.

Works cited-http://cse.ssl.berkeley.edu/bmendez/ay10/2000/cycle/neutronstar.html-http://www.astro.umd.edu/~miller/nstar.html-http://imagine.gsfc.nasa.gov/docs/science/know_l1/pulsars.html-http://filer.case.edu/~sjr16/advanced/stars_neutron.html-http://users.ociw.edu/jrigby/Teach-port/nov4.txt-http://static.newworldencyclopedia.org/thumb/0/01/IsolatedNeutronStar.jpg/300px-IsolatedNeutronStar.jpg-http://www.ph.ed.ac.uk/nuclear/photo/xray_neutronstar.jpg-http://www.spacedaily.com/reports/Neutron_Star_Discovered_Where_A_Black_Hole_Was_Expected.html-http://ircamera.as.arizona.edu/NatSci102/NatSci102/images/neu_star.jpg-http://physicalsciences.ucsd.edu/news/releases/2006/neutron-star-jet_lg.jpg-http://science.nationalgeographic.com/staticfiles/NGS/Shared/StaticFiles/Science/ Images/Content/neutron-star-magnetar-ga.jpg