Individual Stars

The cosmos is full of galaxies, and galaxies are full of stars. Literally billions of stars. Let's look at some of the research that is helping scientists understand how the stars were created and the characteristics of the stars.
Now researchers at MIT, the California Institute of Technology, and the University of California at San Diego have peered far back in time, to the era of the first stars and galaxies, and found matter with no discernible trace of heavy elements. To make this measurement, the team analyzed light from the most distant known quasar, a galactic nucleus more than 13 billion light-years from Earth.
It [the star] is around 27,000 light years away and thus also holds the distance record in this class of objects. Moreover, its high luminosity indicates that J1823-3021A is the youngest millisecond pulsar found to date, and that its magnetic field is much stronger than theoretically predicted. This therefore suggests the existence of a new population of such extreme objects.
These cosmic beacons still pose a few puzzles for scientists: not all radio pulsars can be identified as gamma-ray pulsars and, on the other hand, not all gamma-ray pulsars are "visible" in the radio band. A plausible explanation is the varying width of the light cone over the wavelength range. This may be because emissions at different wavelengths spread out differently. Lower-energy radio waves are bundled more tightly at the magnetic pole of a neutron star field while the cone of high-energy gamma-rays will spread out. Depending on its spatial orientation and intensity of the cone, a pulsar will thus be observed as a radio and/or gamma-ray pulsar. However, other models also describe this phenomenon. To determine the actual cause, as many sources as possible should be examined.
Neutron stars have been called the zombies of the cosmos, shining on even though they're technically dead, and occasionally feeding on a neighboring star if it gets too close. They are born when a massive star runs out of fuel and collapses under its own gravity, crushing the matter in its core and blasting away its outer layers in a supernova explosion that can outshine a billion suns.
Brown dwarfs straddle the boundary between stars and planets. Sometimes described as failed stars, they glow brightly when young, from the heat of formation, but cool down over time and end up with atmospheres that exhibit planet-like characteristics. Scientists think that most brown dwarfs may have formed like stars, in isolation from contracting gas clouds, but some of the puniest free-floaters may have formed like planets around a star and later ejected.
Multimillion-degree gas detected in X-rays (blue) by the Chandra X-ray Observatory comes from shock fronts -- similar to sonic booms --formed by these stellar winds and by supernova explosions. This hot gas carves out gigantic bubbles in the surrounding cooler gas and dust shown here in infrared emission from the Spitzer Space Telescope (orange).
This experiment is beating a record: 'this is the earliest high resolution image of a supernova explosion. From this photograph, we can define the expansion velocity of the shock wave created in the explosion', states Iván Martí from the Institut Max Planck of Radio Astronomy in Bonn (Germany). The full professor in Astronomy and Astrophysics from the University of Valencia, Jon Marcaid, argues that 'with this precision, we can look for the previous star on the earlier galaxy photographs, as well as weigh up better our future observations.'
Now researchers at MIT, the University of California at Santa Cruz and other institutions have detected the first exoplanetary system, 10,000 light years away, with regularly aligned orbits similar to those in our solar system. At the center of this faraway system is Kepler-30, a star as bright and massive as the sun. After analyzing data from NASA's Kepler space telescope, the MIT scientists and their colleagues discovered that the star -- much like the sun -- rotates around a vertical axis and its three planets have orbits that are all in the same plane.
The first evidence of a planet's destruction by its aging star has been discovered by an international team of astronomers. The evidence indicates that the missing planet was devoured as the star began expanding into a "red giant" -- the stellar equivalent of advanced age.

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