Sentences with phrase «hydrogen fusion»

The sun... you know, that massive ball of hydrogen fusion in the sky?

The young star is now stable in that the outward pressure from hydrogen fusion balances the inward pull of gravity.

They are much larger than gas giant planets but fall just short of being large enough to trigger hydrogen fusion.

It is frequently applied to the coolest objects, including K - and M - dwarfs, which are true stars, and brown dwarfs, often referred to as «failed stars» because they do not sustain hydrogen fusion in their cores.

Brown dwarfs are objects intermediate in mass between stars and planets, with masses too low to sustain stable hydrogen fusion in their core, the hallmark of stars like the Sun.

The primary, component A, is a Sun - like star [10] with a stellar classification of F8 V, [5] indicating it is an F - type main - sequence star that is generating energy via hydrogen fusion at its core.

Hydrogen is still available outside the core, so hydrogen fusion continues in a shell surrounding the core.

Brown dwarfs are relatively cool, dim objects that are too massive to be planets, yet they are too small to sustain hydrogen fusion reactions.

«Although fusion is no longer taking place in the core, the rise in temperature heats up the shell of hydrogen surrounding the core until it is hot enough to start hydrogen fusion, producing more energy than when it was a main sequence star,» the Australia Telescope National Facility says on their website.

And those gods were an astrological parody for worship of THE SUN... You know that big bright hydrogen fusion machine in the sky that the church once believed orbited the Earth... See the only way to truly be religious and in particular a Christian is to not ask questions.

Again, astronomy appears to be a «useless» subject, but has yielded a number of practical results, from the discovery of helium to the theories of the properties of gas plasma currently important in hydrogen fusion projects.

Controlled hydrogen fusion may have much greater impact than peaceful atomic fission; for uranium is scarce and expensive, whereas hydrogen is literally as abundant as the ocean.

The generally accepted definition of a planet is very simple: It is a body that orbits its star, and it has to be large enough to become round under self - gravity but not so large that hydrogen fusion takes place in its center.

[10] The ZAMS curve can be calculated using computer models of stellar properties at the point when stars begin hydrogen fusion.

As the star's outer layer begins to swell from the heat of renewed hydrogen fusion before cooling from expanion, this hydrogen - burning zone moves outward, cools, and shuts down while its underlying of helium begins to fuse in turn.

Some of these objects have masses large enough to support hydrogen fusion and are therefore stars, but most are of substellar mass and are therefore brown dwarfs.

If we can achieve a negative growth rate for humanity, and invent hydrogen fusion power plants, there would be no need to cut back on energy use or consumerism at all.

Brown dwarfs were originally called black dwarfs, a classification for dark substellar objects floating freely in space which were too low in mass to sustain stable hydrogen fusion.

And in the past several years, disks seemed equally likely around brown dwarfs: gaseous balls less than 75 times the mass of Jupiter, unable to ignite sustained hydrogen fusion.

With no more energy from hydrogen fusion to counteract the enormous inward pull of their gravity, the stars collapsed until all of their mass was compressed into a point of infinite density.

Hydrogen fusion continues only in the star's outer layers, which causes it to expand.

Brown dwarfs are too big to be planets but too small to be true stars, as they have too little mass to trigger hydrogen fusion reactions at their cores, the source of the energy output in larger stars.

He and co-author Michael Liu of the University of Hawaii have found that an object must weigh at least 70 times the mass of Jupiter in order to start hydrogen fusion and achieve star - status.

According to Professor Jim Kaler at the University of Illinois» Department of Astronomy, Rana started life as a main sequence F8 dwarf (somewhat hotter and brighter than Sol with slightly greater mass) around 7.5 billion years ago, but core hydrogen fusion has ceased causing the star to expand and cool as an active subgiant before becoming much brighter and larger «as a true giant star» through core helium fusion.

Other photographed objects have been too massive to be conclusively labeled planets, falling instead into the brown dwarf category (objects about eight to 80 Jupiters in size that lack sufficient mass to ignite hydrogen fusion in their cores, thereby never becoming true stars); have been found to themselves orbit brown dwarfs rather than stars; or have not been shown to be gravitationally bound to a star.

Below a certain size, Kumar calculated, you would end up with degenerate objects with too little mass to sustain hydrogen fusion, and they would fizzle out.

Hydrogen fusion would be perfectly adequate.

Brown dwarfs are too small to sustain the hydrogen fusion process that powers stars.

This model describes three types of forces: electromagnetic interactions, which cause all phenomena associated with electric and magnetic fields and the spectrum of electromagnetic radiation; strong interactions, which bind atomic nuclei; and the weak nuclear force, which governs beta decay — a form of natural radioactivity — and hydrogen fusion, the source of the sun's energy.

Brown dwarfs are too small to sustain the hydrogen fusion process that fuels stars, so after formation they slowly cool and contract over time and their surface gravity increases.

Brown dwarfs are not considered stars because they are too small to fuse hydrogen in their cores — they don't have the gravitational oomph in their core to sustain hydrogen fusion, but, depending on how massive they are, they do have enough mass to sporadically fuse elements like lithium and deuterium.

When their central temperatures reach values comparable to 107 K, hydrogen fusion ignites in their cores, and they settle down to long stable lives on the main sequence.

If HD 181433 has a mass less than Sol's but is more evolved (i.e., where it may have already shut down hydrogen fusion in its helium - rich core), then it may be significantly older than Sol's 4.6 billion years.

That would mean the objects — «failed» stars whose masses are below the limit needed to sustain stable hydrogen fusion — could be as plentiful as the M - dwarfs that far outnumber any other type of star in the galaxy.

When the core runs out of hydrogen fuel, it will contract under the weight of gravity; however, some hydrogen fusion will occur in the upper layers.

The core that is left behind will be a white dwarf, a husk of a star in which no hydrogen fusion occurs.

Brown dwarfs are too small to sustain the hydrogen fusion process that fuels stars and allows them to remain hot and bright for a long time.

Actually there's new research stating that stars like our Sun ramp up their hydrogen fusion as they age becomming brighter and hotter.