STARS

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The brilliant flash of an exploding star's shockwave [shock breakout] has been captured for the first time in visible light by NASA's Kepler Space Telescope.

Scientists analyzed light captured by Kepler every 30 minutes over a three-year period from 500 distant galaxies, searching some 50 trillion stars.

2 of these massive stars exploded while in Kepler's view. The first behemoth, KSN 2011a, is nearly 300 times the size of our sun and a mere 700 million ly from Earth. The second, KSN 2011d, is roughly 500 times the size of our sun and around 1.2 billion ly away. Supernovae like these are known as Type II.

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The explosive death of a star, called KSN 2011d, as it reaches its maximum brightness takes 14 days. The shock breakout itself lasts only about 20 minutes. This type of star is called a red supergiant star and it's 20 000 times brighter than our sun. As the supergiant star goes supernova, the energy traveling from the core reaches the surface with a burst of light that is 130 million times brighter than the sun. The star continues to explode and grow reaching maximum brightness that is about 1 billion times brighter than the sun.

 

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Supernova 2012cg

Located 50 million ly away in the constellation Virgo, the supernova is blowing up next to a companion star, and the explosion impacts the companion star. The side of that companion star that's hit gets hot and bright. The excess blue light is coming from the side of the companion star that gets heated up.

Combined with the models, the observations indicate that the binary companion star has a minimum mass of six suns.

 

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The yellow-orange host galaxy (left) before the supernova, and afterwards (right) when the ASASSN-15lh super-luminous supernova's blue light outshines its host galaxy.

ASASSN-15lh, was discovered in 2015 and is possibly the most luminous and powerful explosion ever seen, more than 500 times brighter than normal supernovae. For more than a month its luminosity was 20 times brighter than the whole Milky Way galaxy.

 

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Astronomers discover white dwarf star with an atmosphere completely dominated by oxygen SDSS J124043.01+671034.68 (SDSS J1240+6710 for short).

Stars born with masses ≤ 8-11 solar masses end their lives as small, hot, and extremely dense objects known as white dwarfs. Their atmospheres are dominated by the lightest elements, such as hydrogen or helium, because gravitational diffusion brings the lightest element to the surface.

Scientists identified oxygen-neon white dwarf SDSS J1240+6710 with its outer layer of light elements stripped away, revealing a nearly pure layer of oxygen.

Oxygen, neon, and magnesium are the products of carbon burning, which occurs in stars at the high-mass end of pre-white dwarf formation. SDSS J1240+6710 has a mass of 0.56 solar masses and is located 1174 ly away.

One possibility is that interactions with a nearby companion in a binary star caused this unique star to bare its oxygen envelope.

Another possibility is that a massive pulse of burning carbon from the center of the star, emanating outwards, eliminated the lighter elements.

 

[Drone]

This is so mysterious exciting magnificent and simply mind blowing that I can hardly breath ...


PB3877 is a hyper-velocity wide binary star zooming through the outskirts of the Milky Way. This binary star is moving nearly at the escape velocity of our galaxy.

The surface of the hot compact star is > 5 times hotter than the Sun, while the companion is a thousand degrees cooler than our Sun. The system was determined to be 18 000 ly away. The mass of the hot compact star is .5 times the mass of our Sun, and the companion is .7 times the mass of the Sun.

PB3877 could be an intruder that has been born in another galaxy and may or may not leave the Milky Way again.

 

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My favorite star - Alpha Virginis (Spica)

Alpha Virginis is the 15th brightest star in the night sky, in part because it is relatively nearby, only ~ 250 ly away. Spica is a "spectroscopic" binary, two stars orbiting each other and too close together to separate visually. The stars in Spica are, moreover, an unusual pair: They are very close, separated by ~ 28 solar-radii, and orbit each other in only 4.01 days. This puts them so close together that their mutual gravity tidally distorts their atmospheres, with the result that the stars are not spherical. Oh, and the more massive star pulses in size and luminosity. Spica's two stars are both massive, at 11.4 and 7.2 solar-masses, respectively.

 

[Caring1]

That might get messy if and when they collide.

 

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By using multiple telescopes, scientists were able to get one of the best maps ever of a star other than the Sun.

A star like the Sun has an internal driving in the form of a magnetic field that can be seen on the surface as sunspots. Now astrophysicists from the Niels Bohr Institute have observed a distant star ζ Andromedae with a different positioning of sunspots and this indicates a magnetic field that is driven by completely different internal dynamics.

Stars are glowing balls of gas that through atomic processes release energy that is emitted as light and heat. In the interior of the star are charged particles that swirl and spin and thereby create a magnetic field that can burst out onto the surface of the star, where it appears as starspots. Starspots are cool areas caused by the strong magnetic fields where the flow of heat is slowed. On the Sun the sunspots are seen in a belt around the equator, but now scientists have observed a large, distant star where sunspots are located near the poles.

ζ Andromedae is an old active massive star that is ~ 16 times the size of the Sun in diameter. It's located 180 ly away. It's part of a binary star system, causing the stars to rotate more quickly. The larger of the two stars, rotates at 40 km/s. The Sun rotates at 2 km/s.

 

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More info on Zeta Andromedae (aka HD 4502) and pics:

http://www.sci-news.com/astronomy/zeta-andromedae-surface-images-03841.html
http://ns.umich.edu/new/releases/23792-starspot-images-give-insights-into-early-sun

ζ Andromedae is a tidally locked close binary system consisting of an orange K-type giant star and an unseen lower-mass companion star.

 

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ALMA Observes First Protoplanetary Water Snow Line Thanks to Stellar Outburst

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The upper right image shows Polaris A and its distant companion Polaris B, as viewed by Hubble. They are separated by ~ 240 billion miles. Polaris B, the wide companion, is visible in small telescopes, and was first noticed by William Herschel in 1780. The close companion, Polaris Ab was known to exist from its gravitational tug on Polaris A, but has only been seen directly now using Hubble (lower right image). The companion is only 2 billion miles from Polaris A.

The triple system is 430 ly away.

 

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Star Size Comparison 2

 

[Caring1]

Holy shite, way to make us feel insignificant
I hope my other self in another multiverse realises one of us is going to die before the other, and we'll never know which one, or perhaps we all die simultaneously.

 

[hat]

The only thing it takes to make me feel insignificant is to look around, not even towards the heavens. Of course, it remains true that the more upward you look, the more insignificant you and even your surroundings appear...

 

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Resembling the puffs of smoke and sparks from a summer fireworks display, this Hubble image depicts the delicate filaments debris from a stellar explosion in a neighboring galaxy.

N 49, or DEM L 190 is a supernova remnant whose light would have reached Earth thousands of years ago. This filamentary material will eventually be recycled into building new generations of stars. Our own sun and planets are constructed from similar debris of supernovae that exploded in the Milky Way billions of years ago.

This seemingly gentle structure also harbors a very powerful spinning neutron star that may be the central remnant from the initial blast. It is quite common for the core of an exploded supernova star to become a spinning neutron star (pulsar) after the immediate shedding of the star's outer layers. In the case of N 49, not only is the neutron star spinning at a rate of once every 8 seconds, it also has a super-strong magnetic field a quadrillion times stronger than Earth's magnetic field. This places this star into the exclusive class of objects called magnetars.

 

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Bright star named Hen 2-427 (otherwise known as WR 124).

It's a Wolf-Rayet star, a rare type of star known to have very high surface temperatures – well over 25 000ºC, next to the Sun's comparatively cool 5500ºC – and enormous mass, which ranges over 5-20 times our Sun's. Such stars are constantly losing vast amounts of mass via thick winds that continuously pour from their surfaces out into space.

A new image of supernova remnant G11.2-0.3 is being released in conjunction with this week's workshop titled "Chandra Science for the Next Decade" being held in Cambridge, Massachusetts.

The supernova explosion produced a pulsar - a rapidly rotating neutron star - and a pulsar wind nebula, shown by the blue X-ray emission in the center of the remnant. The combination of the pulsar's rapid rotation and strong magnetic field generates an intense electromagnetic field that creates jets of matter and anti-matter moving away from the north and south poles of the pulsar, and an intense wind flowing out along its equator.

•New Chandra data raise new questions about the timing of its origin.

•Previously, G11.2-0.3 was associated with an event recorded by Chinese observers in 386 CE.

•Chandra observations show that dense gas clouds lie along the line of sight between Earth and G11.2-0.3.

•This new information means that the supernova explosion would have been too faint to be seen with the naked eye from Earth.

•This leaves the nature of the observed 386 CE event a mystery.

 

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Brilliant vids

 

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New images by ESA:

This image of the sky around the bright star Alpha Centauri AB also shows the much fainter red dwarf star, Proxima Centauri, the closest star to the Solar System. The picture was created from pictures forming part of the Digitized Sky Survey 2. The blue halo around Alpha Centauri AB is an artifact of the photographic process, the star is really pale yellow in color like our Sun. (Download original image 714 MB)

The relative sizes of a number of objects, including the three (known) members of Alpha Centauri triple system and some other stars. Sun and Jupiter are also shown for comparison.

 

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Dying star IRC+10216 is surrounded by a large volume of high-temperature water vapor.

A swollen red giant star is having the final, spectacular party of its life. If it weren't for these dying stars enriching the chemistry of the matter in the galaxy, there would be no rocky planets and no life.

 

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An age-defying star designated as IRAS 19312+1950 exhibits features characteristic of a very young star and a very old star. The object stands out as extremely bright inside a large, chemically rich cloud of material, as shown in this image from NASA's Spitzer Space Telescope. A NASA-led team of scientists thinks the star – which is ~ 10 times as massive as our sun and emits about 20000 times as much energy – is a newly forming protostar.

Scientists found large quantities of ices made from water and carbon dioxide in the cloud around the object. These ices are located on dust grains relatively close to the star, and all this dust and ice blocks out starlight making the star seem dimmer than it really is.

 

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Eta Carinae is a celebrity among objects in the Universe. An hourglass-shaped, billowing cloud of glowing gas and dust enshrouds the star and its companion. Known as the Homunculus nebula, the cloud consists of stellar material hurled into space during the Great Eruption (19th-century brightening).

This animated view of Hubble Space Telescope images taken between 1993 and 2014 reveals how much the mass ejections from Eta Carinae have moved outward into space, some at a speed of 2 million mph.

The expansion rate of gas that was far outside the Homunculus indicated that it was moving slowly and must have been ejected centuries before the Great Eruption. In fact, the motions of the outer material point to two separate eruptions in the mid-13th and mid-16th centuries.


Eta Carinae is a binary system located 7000 ly away. Two very massive stars orbit each other every 5.5 years. Both are much bigger than our sun and at least one of them is nearing the end of its life. These are very large stars that appear very volatile, even when they're not blowing off nebulae. They have a dense core and very fluffy envelopes. If you replaced our sun by the larger of the two, which has ~ 90-100 solar masses, it could very well extend into the orbit of Mars.

 

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Brown Dwarfs and Quark Novae explained.

 

[dont whant to set it"']

Second video nu mai este disponibil(no longer available)

 

[EarthDog]

WOrks for me.

 

[Drone]

Second video nu mai este disponibil(no longer available)

You mean quark nova video? Here's other video by physicsworld where the author himself explains it. Sound quality isn't really good but it's audible and provides thorough scientific explanation.

Short and nice videos by science & u

Dr. Emily Rice explains where the term "nebula" comes from and what it is used to define.

Dr. Emily Rice explains what a Brown Dwarf is and how it differs from other stars.

 

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For decades, astronomers have known there is a dense, compact source at the center of RCW 103 - supernova remnant located ~ 9000 ly from us.

RCW 103's central source, known officially as 1E 161348-5055 is a young magnetar (~ 2000 years old). It's rotating once every 24000 seconds (6.67 hours), much slower than the slowest magnetars known until now, which spin around once every 10 seconds. This would make 1E 1613 the slowest spinning neutron star ever detected.

While it's still unclear why 1E 1613 is spinning so slowly, scientists do have some ideas. One leading scenario is that debris from the exploded star has fallen back onto magnetic field lines around the spinning neutron star, causing it to spin more slowly with time. Searches are currently being made for other very slowly spinning magnetars to study this idea in more detail.