How does interstellar absorption affect the classification of a supernova remnant?

Type 1a supernova are standard candles, because their light curves are always very similar. This permits to measure their distance in two independent ways: - the total amount of light scales as 1/distance^2 - the redshift Absorption by the interstellar medium affect both of these measurement. It absorbs light so to total intensity decreases, and it absorbs more blue light than red, making the object seem redder.

What would happen if a supernova happened in the atmosphere?

There's no such thing as a miniature supernova. A supernova within a hundred light years would vaporize the Earth.

How can you measure the strength of a supernova?

Supernova nucleosynthesis http://en.wikipedia.org/wiki/Supernova_nucleosynthesis Synthesis of elements heavier than iron mainly starts with the elements around and including iron, which have previously built up in the core of a heavy star during the earlier phases of the star's life. There is a high neutron flux during the supernova and there can be a series of rapid neutron captures, with subsequent decays, that lead to a suite of heavy elements http://en.wikipedia.org/wiki/R-process There is also a slow neutron capture process that operates inside Asymptotic Giant Branch stars which builds up heavy elements over a long period of time. http://en.wikipedia.org/wiki/S-process Here's the kick-off page for reading up on how the elements are synthesized in stars http://en.wikipedia.org/wiki/Stellar_nucleosynthesis

How are supernova explosions useful is measuring the distance of galaxies?

Supernovas come in different types, distinguishable by their spectra and the shape of their light curves (how they get brighter and fainter with time). Type Ia appears to consistently have about the same luminosity in nearby galaxies. Therefore, it is assumed that Type Ia supernovas are about the same luminosity everywhere in the Universe, a "standard candle". This assumption allows the calculation of the "luminosity distance" to distant Type Ia supernovae.

How to simulate a supernova for a science project?

My astronomy professor has a simple but great "supernova simulator" - three rubber balls, with holes in the center, different sizes, on a stick. How does it simulate a supernova, then? It's dropped, large ball first; the other two balls bounce away from it at high speed on impact. This simulates the way the rebound off the core causes the star to explode. To make it flashy, use the bounciest balls you can find - if you can find ones that will light up even with holes in them, even better. Failing that, ones with glitter should work nicely. But even with plain ones, the effect should be eye-catching.

What is a supernova compared to a planetary nebula?

The remnants of a supernova will be either a neutron star or a black hole. To leave behind a black hole, the original star would have to be at least 10 times more massive than our sun. A neutron star would require an original star between 5 to 9 solar masses.

What is the difference between a supernova and a supernova remnant?

Supernova exploding star: a catastrophic explosion of a large star in the latter stages of stellar evolution, with a resulting short-lived luminosity from 10 to 100 million times that of the Sun

What makes the Crab Nebula supernova remnant unusual as a supernova remnant?

Your answer can be found here - http://en.wikipedia.org/wiki/Crab_Nebula

supernova??

Please do NOT confuse astrology, which is garbage claiming that the positions of stars and planets influence one's fate, with astronomy, which is a real science. A company that would bring tourists to see supernovae up close could be called "The light fantastic".

Supernova?

When a massive star fuses a sufficient amount of matter into iron at its core, the forces holding the electrons in their orbits around the nuclei of the atoms at the center are overwhelmed by gravitational pressure, and they collapse into the nuclei forming neutronium. The entire core collapses into a mass of solid neutrons, and the explosive release of energy blows the outer layers of the star outward, causing fusion into tranferric elements.