Sentences with phrase «on white dwarfs»

Unlike supernovae of Type II, the matter ejected in Type - I supernovae consists almost entirely of the heavier elements (spectrum of some elements in Tycho's SNR), as there is very little hydrogen left on white dwarfs.

late stages of stellar evolution: white dwarfs, isolated and in interacting binary systems, stellar explosions on white dwarfs (novae and type Ia supernovae).

The companion star may have dumped its gas on the white dwarf until the added weight sparked a thermonuclear detonation.

NEWSPAPER obituaries of Subrahmanyan Chandrasekhar, who died last month aged 84, all highlighted the single achievement for which he will be best remembered — his work on white dwarf stars.

The brown dwarf was effectively hidden by the dust until we looked with the right instrument,» added Parsons, «but when we observed SDSS 1557 in detail we recognised the brown dwarf's subtle gravitational pull on the white dwarf.»

After the nova burst, gas from the regular star begins to build up again on the white dwarf's surface.

The buildup of helium on the white dwarf eventually would have triggered an explosion, called a supernova.

Moreover, any «nova outbursts» that occur on the white dwarf are relatively weak and eject little matter, so that the white dwarf grows in mass.

Not exact matches

One of the trailers for the kid's movie has been removed, as it shows two of the dwarves spying on Snow White as she undresses.

At least Bercow has solace on hand from his wife, Sally, who tweeted: «If Mr B's a dwarf then I'm Snow White.

Warren Redlich, the Libertarian, has pictures of the candidates on his website in a graphic called «Snow White and the Seven Dwarfs.»

«The gas which forms the major part of the insterstellar medium,» explains Jorge García Rojas, a researcher at the IAC who is the first author on the paper «can be observed because its atoms are ionized by the photons emitted by the hot stars embedded inside it (which can either very massive stars, or white dwarfs, which are also very hot).

OXYGEN on a planet might be a sign of life, but in two odd white dwarf stars it could indicate a narrow escape from violent death.

Within about a million years the object will be destroyed, leaving a thin dusting of metals on the surface of the white dwarf.

Within the next million years or so, all that will remain of these asteroidal bits is a thin metal dusting on top of an innocent - looking white dwarf star.

The diffuse cloud in this image, taken with the Carnegie Institution for Science's Swope telescope in Chile, is the shell of hot hydrogen gas ejected by a white dwarf star on March 11, 1437.

By multiplying the density of the newfound cool dwarfs by the volume of the galactic halo, Oppenheimer's team estimates that white dwarfs make up, by the most conservative estimate, at least 3 % of the total galactic dark matter, they report online in Science on 23 March.

Imagine being able to view microscopic aspects of a classical nova, a massive stellar explosion on the surface of a white dwarf star (about as big as Earth), in a laboratory rather than from afar via a telescope.

The observations provided the highest - precision data ever on tiny changes in a white dwarf's brightness and, indirectly, its vibrations.

That configuration would help it pinpoint the sources of gravitational waves on the sky and allow it to see the longer - wavelength ripples from a wider range of sources including binary white dwarfs, slower - spinning pulsars and intermediate - mass black holes weighing hundreds or thousands of suns.

If enough material, mostly in the form of hydrogen gas, accumulates on the surface of the white dwarf, nuclear fusion reactions can occur and intensify, culminating into a cosmic - sized hydrogen bomb blast.

In their new study, the Leicester - led team assesses whether these laws are the same within the hot, dense conditions in the atmosphere of a dying white dwarf star as here on Earth.

In strong fields such as those present in the atmospheres of white dwarfs (on the order of 105 teslas) and other stellar objects, our calculations suggest that this mechanism underlies the strong bonding of H2 in the Σ3u + (1σg1σu *) triplet state and of He2 in the Σ1g + (1σg21σu * 2) singlet state, as well as their preferred perpendicular orientation in the external field.

And that pressure, acting on the carbon - rich makeup of the white dwarf, may have crystallized much of it to the particular form of carbon we call diamond.

H1504 +65 is the hottest white dwarf on record — and the only known star lacking helium and hydrogen.

Old stars are coming unglued on the way to becoming white dwarfs — and astronomers confidently predict that in 5 billion years the sun will be an old star.

A stellar ember called a white dwarf exploded after gorging on material stolen from its neighbour.

Neither study searched for the stars responsible for so - called type Ia supernovae, which are explosions of white dwarf stars that have grown overweight by feasting on material from a companion star.

In some alternate theories of gravity that could take over if general relativity turns out to be wrong, the neutron star could have gravitational effects going on inside it that the relatively willowy white dwarf would not.

Hubble images also had glimpsed a white spot on the dwarf planet, but its nature is still unknown.

These are thought to arise when a normal star spills its outer layers of gas on its compact white dwarf partner.

Even protostars — these are young stars that are just forming and making their own planetary disks and so on — they make very powerful outflows called, the same sort of jets obviously moving at slower speeds, but they are full of plasma, that is flowing out at high speed; white dwarfs, neutron stars, black holes big and small, they seem able to do this task, it really seems to be a very common phenomenon.

Three years ago, astronomers put a white dwarf on a scale and watched the needle move.

The team believes that the explosion of a white dwarf partner propelled US 708 on its intergalactic escape route (as depicted in the simulation above).

They hypothesized this object could be the result of a white dwarf with a helium layer on its surface.

As a white dwarf draws off hydrogen - rich material from a binary companion over millions of years, Gilfanov says, it experiences a steady process of nuclear fusion on its surface that gives off tremendous amounts of radiation.

It was first assumed to be a nova — a white dwarf that pulls gas off a companion until it triggers a thermonuclear explosion on its surface.

Type Ia supernovas are known to form when a white dwarf merges with another star, like a puffed - up red giant (as opposed to Type II supernovas, which form when a single star dies and collapses on itself).

With JWST, a few hours of integration time will be enough to detect Earth - like levels of water vapor, molecular oxygen, carbon dioxide and other generic biosignatures on planets orbiting a white dwarf; beyond that, observing the same planet for up to 1.7 days will be enough to detect the two CFCs in concentrations of 750 parts per trillion, or 10 times greater than on Earth.

The behavior of a star now depends on its mass, with stars below 0.23 solar masses becoming white dwarfs, while stars with up to 10 solar masses pass through a red giant stage.

My research concentrates on the study of exploding stars — mainly nova outbursts caused by thermonuclear explosions on the surface of white dwarfs in binary star systems.

Because these planets are light years away, and because the reflected light is incredibly dim, the James Webb Space Telescope will only be able to do this for large planets that orbit red and white dwarfs — but still, it's incredibly exciting to think that we might be able to identify signs of life from all the way over here on our little blue marble.

The energy output of a white dwarf is so small that the object can go on shining mainly by radiating away its stored energy until virtually none is left to emit.

«And someone should also talk to the astronomers: «The collapse to a white dwarf takes place over tens of thousands of years, (Wikipage on gravitational collapse)».

But contained within these dead stars, called white dwarfs, is the early history of our galaxy, providing clues on how it came to be.

Scientists from a large international collaboration (Oxford, AWE, CEA, LULI, Observatoire de Paris, University of Michigan and University of York) have succeeded for the first time to generate a laboratory analogue of a strong shock that takes place when matter falls at very high speed on the surface of extremely dense stars called white dwarfs.

Lick Observatory (Lick 3 - m Telescope) Short exposure on left reveals the faint white dwarf Sirius B, then located about 25 AUs below Sirius A, which is absent in the overexposed, longer exposure on right

However, in rare instances, two of these objects orbit each other so closely ---- orbiting every few minutes ---- so that the helium from the lighter of the two gets pulled off by tidal forces and accumulates on the more massive white dwarf.

The team based its results on an analysis of 70 of the hottest white dwarfs detectable by Hubble in a small region of the bulge among tens of thousands of stars.

Building on past observations of the white dwarf called SDSSJ1043 +0855 (the dead core of a star that originally was a few times the mass of the Sun), which has been known to be gobbling up rocky material in its orbit for almost a decade, the team used Keck Observatory's HIRES instrument fitted to the 10 - meter Keck I telescope as well as data from the Hubble Space Telescope to measure and characterize the material being accreted by the star.