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Until now, supernovae have come in two main versions

In one scenario, a huge star, 10 to 100 times more massive as our Sun, collapses causing a colossal stellar explosion

Type Ia supernovae, occurs when material from a parent star streams onto the surface of a white dwarf. Over time, so much material falls onto the white dwarf that it raises the core temperature igniting carbon and causing a runaway fusion reaction. This event completely disrupts the white dwarf and results in a colossal stellar explosion

type Iax, release somewhere between 1% and 50% the energy of a type Ia supernova

spectra of type Iax stars don't include any signs of hydrogen

Type Iax supernovae most likely form in binary star systems when a superdense, carbon- and oxygen-rich white dwarf star (center of disk at left) robs material from its helium-rich partner, eventually accumulating enough mass on its surface to trigger an explosion

This nebula with a giant star at its center

th stars had identical rings of the same size and age, which were travelling at similar speeds; both were located in similar HII regions; and they had the same brightness

no one can predict when a star will go supernova,

It remains unclear what precisely happens

The helium in the companion star's outer shell might undergo nuclear fusion, blasting a shock wave at the white dwarf that makes it detonate

On the other hand, all the helium the white dwarf accumulated from its companion star could alter the density and temperature of the white dwarf's interior, forcing carbon, oxygen and maybe helium within the star to fuse, triggering an explosion

known as fast radio bursts (FRBs), above the plane of our Milky Way Galaxy.

These bursts gave off more energy in a millisecond than the sun does in 300,000 years

The bursts ranged from 5.5 to 10 billion light-years away, meaning it took the light from some of them 10 billion years to reach Earth. (The Big Bang 

Supernova

In 1006, Chinese and Arabic astronomers noted a supernova. The speed of the still-expanding shock wave was measured nearly a millenium later.* This is was history's brightest "new star" ever recorded, at first seen to be brighter than the planet Venus. It occurred in our Milky Way galaxy, appearing in the southern constellation Lupus, near the star Beta Lupi. It was also recorded by observers in Switzerland, Italy, Japan, Egypt and Iraq. From the careful descriptions of the Chinese astronomers of how the light varied, that it was of apparently yellow color and visible for over a year, it is possible that the supernova reached a magnitude of up to -9. Modern measurements of the speed of the shock wave have been used to estimate its distance

Scientists are crunching one more set of numbers to find out for sure.

New data from the spacecraft indicate that the historic moment of its exit from the solar system might have come and gone two months ago

For two years now, data beamed back to Earth by Voyager 1 has hinted at its close approach to the edge of the solar system, a pressure boundary called the heliopaus

American physicist David Wineland

and French physicist Serge Haroche speaks to the media in Paris after they were named winners of the 2012 Nobel Prize in physics.

for experiments on quantum particles that have already resulted in ultra-precise clocks and may one day help lead to computers many times faster than those in use today.

Curiosity's Radiation Assessment Detector (RAD) is the first instrument to measure the radiation environment during a Mars cruise mission from inside a spacecraft that is similar to potential human exploration spacecraft

The findings,

indicate radiation exposure for human explorers could exceed NASA's career limit for astronauts if current propulsion systems are used.

A metal-poor star located merely 190 light-years from the Sun is 14.46+-0.80 billion years old, which implies that the star is nearly as old as the Universe

results emerged from a new study

Such metal-poor stars are (super) important to astronomers because they set an independent lower limit for the age of the Universe