Astronomy Chapter 13 & 14 The Death of Stars Notecards

Type 2 Supernova

A Type II supernova (plural: supernovae or supernovas) results from the rapid collapse and violent explosion of a massive star. A star must have at least 8 times, and no more than 40-50 times, the mass of the Sun (M☉) to undergo this type of explosion.

Binary Pulsar

A binary pulsar is a pulsar with a binary companion, often a white dwarf or neutron star. (In at least one case, the double pulsar PSR J0737-3039, the companion neutron star is another pulsar as well.)

Black Dwarf

A black dwarf is a theoretical stellar remnant, specifically a white dwarf that has cooled sufficiently that it no longer emits significant heat or light.

Millisecond Pulsar

A millisecond pulsar is a type of radio or X-ray pulsar that has a rotation period measured in a small number of milliseconds, usually below 30 ms. History. The first millisecond pulsar was the celebrated 1.55 ms pulsar PSR B1937+21, which, for over 20 years was the fastest pulsar known.

Supernova Remnant

A supernova remnant (SNR) is the structure resulting from the explosion of a star in a supernova. The supernova remnant is bounded by an expanding shock wave, and consists of ejected material expanding from the explosion, and the interstellar material it sweeps up and shocks along the way.

Type 1 Supernova

A type Ia supernova is a type of supernova that occurs in binary systems (two stars orbiting one another) in which one of the stars is a white dwarf. The other star can be anything from a giant star to an even smaller white dwarf.

Gamma Bursters

Gamma-ray bursts (GRBs) are extremely energetic explosions that have been observed in distant galaxies. They are the brightest electromagnetic events known to occur in the universe. ... A subclass of GRBs (the "short" bursts) appear to originate from a different process: the merger of binary neutron stars.

Chandrasekhar Limit

The Chandrasekhar limit is the maximum mass of a stable white dwarf star. The limit was first indicated in papers published by Wilhelm Anderson and E. C.

Singularity

The remnant then collapses to a black hole—a singularity, or point of zero volume and infinite density hidden by an event horizon at a distance called the Schwarzschild radius, or gravitational radius.

X-Ray Bursters

X-ray bursters are one class of X-ray binary stars exhibiting periodic and rapid increases in luminosity (typically a factor of 10 or greater) that peak in the X-ray regime of the electromagnetic spectrum.

Schwarzchild Radius

a black hole of a kind supposed to result from the complete gravitational collapse of an electrically neutral and nonrotating body, having a physical singularity at the center to which infalling matter inevitably proceeds and at which the curvature of space-time is infinite. A Schwarzschild radius is the radius of the boundary of a hole of this type.

Neutron Star

a celestial object of very small radius (typically 18 miles/30 km) and very high density, composed predominantly of closely packed neutrons. Neutron stars are thought to form by the gravitational collapse of the remnant of a massive star after a supernova explosion, provided that the star is insufficiently massive to produce a black hole.

Pulsar

a celestial object, thought to be a rapidly rotating neutron star, that emits regular pulses of radio waves and other electromagnetic radiation at rates of up to one thousand pulses per second.

Black Hole

a region of space having a gravitational field so intense that no matter or radiation can escape.

Planetary Nebula

a ring-shaped nebula formed by an expanding shell of gas around an aging star.

Accretion Disk

a rotating disk of matter formed by accretion around a massive body (such as a black hole) under the influence of gravitation.

Nova

a star showing a sudden large increase in brightness and then slowly returning to its original state over a few months.

Supernova

a star that suddenly increases greatly in brightness because of a catastrophic explosion that ejects most of its mass.

Event Horizon

a theoretical boundary around a black hole beyond which no light or other radiation can escape.