if you want to remove an article from website contact us from top.

    when a white dwarf star collects matter from a neighboring star, fusion reactions on the surface of the white dwarf cause

    James

    Guys, does anyone know the answer?

    get when a white dwarf star collects matter from a neighboring star, fusion reactions on the surface of the white dwarf cause from EN Bilgi.

    26 Flashcards

    Study with Quizlet and memorize flashcards terms like the exhaustion of hydrogen at its core., swells up and becomes a red giant., dropping temperature and constant brightness. and more.

    26

    the exhaustion of hydrogen at its core.

    Click card to see definition 👆

    The first red giant phase of a star is caused by

    Click again to see term 👆

    swells up and becomes a red giant.

    Click card to see definition 👆

    When the hydrogen fuel runs out at the center of a main sequence star, the star

    Click again to see term 👆

    1/20 Created by newmanma3

    Terms in this set (20)

    the exhaustion of hydrogen at its core.

    The first red giant phase of a star is caused by

    swells up and becomes a red giant.

    When the hydrogen fuel runs out at the center of a main sequence star, the star

    dropping temperature and constant brightness.

    The red subgiant stage of a star is best described by

    red subgiant.

    A star that is cooling and swelling just enough to keep the same total brightness could be a

    decreases but not to its main sequence size.

    When a red giant star begins to burn helium, its diameter

    helium at their centers.

    Stars on the horizontal branch of the HR diagram are burning

    an explosion in the helium core.

    The first red giant stage of a one solar-mass star's life usually ends with

    the explosive ignition of a star's helium core.

    The 'helium flash' refers to

    the exhaustion of helium at its core.

    The red supergiant phase of a star is caused by

    swells up and becomes a red supergiant.

    When the helium fuel runs out at the center of a horizontal branch star, it

    electrons touch each other.

    The core of a red supergiant star stops shrinking because its

    prevents carbon-burning from starting.

    The formation of electron-degenerate matter in the carbon core of a solar-mass red super giant

    a star becomes a white dwarf.

    A planetary nebula forms when

    planetary nebula.

    The formation of a new white dwarf is usually accompanied by a

    the Earth.

    The size of a typical white dwarf star is comparable to the size of

    white dwarf star.

    A star that is approximately the size of the Earth is probably a

    decreases from millions of degrees K to zero.

    The surface temperature of a white dwarf star

    lower left corner.

    On a HR diagram, a visible white dwarf star is in the

    a white dwarf steals fuel from a neighbor.

    A nova occurs when novas

    When a white dwarf star collects matter from a neighboring star, fusion reactions on the surface of the white dwarf cause

    Sets with similar terms

    Astronomy 101 Module 9

    23 terms benjamin_danzi

    1.7/1.8 Stars and Galaxies

    33 terms alumnole

    Stellar Evolution

    19 terms Shelby_Back1

    ASTR 209 - Ch.20: Stellar Evolution

    52 terms alivia278

    Sets found in the same folder

    22

    19 terms newmanma3

    23

    5 terms newmanma3

    8

    15 terms newmanma3

    24

    15 terms newmanma3

    Other sets by this creator

    BB final (all these frickin numberz)

    72 terms newmanma3

    WBC practical

    23 terms newmanma3

    Unit 2

    8 terms newmanma3

    Ab. heme Practical 1

    43 terms newmanma3

    Verified questions

    ASTRONOMY

    The largest observatory complex in the world is on Mauna Kea, the tallest mountain on Earth. What are some factors astronomers consider when selecting an observatory site? Don’t forget practical ones. Should astronomers, for example, consider building an observatory on Denali (Mount McKinley) or Mount Everest?

    Verified answer ASTRONOMY

    If you had a time machine, plus superpowers sufficient to modify or move entire planets, what would you change about Mars, as it was forming, to make its surface environment remain more Earth-like to the present day? How about Venus?

    Verified answer ASTRONOMY

    Which labeled constellation do you see highest in the southern sky?

    Verified answer ASTRONOMY

    Why are light-years more convenient than miles, kilometers, or astronomical units for measuring certain distances?

    Verified answer

    Other Quizlet sets

    DAT test 5

    62 terms vrt214

    Ultrasound Physics Midterm

    112 terms kahla_allen

    MRU7.8 Geography and Economic Growth

    10 terms alehdez14

    Human anatomy

    19 terms anb0090PLUS

    Related questions

    QUESTION

    Which kind of star is most likely to be part of the spheroidal population (2 parts)?

    2 answers QUESTION

    A. quickly escapes from the Sun in a straight line

    10 answers QUESTION

    t/f: convection involves cool gas rising toward the solar surface, and hot gas sinking into the interior

    4 answers QUESTION

    suppose you are in a jet airliner traveling at a constant speed of 400 in a constant direction. all windows are blocked. what experiment can you do to determine that you are in fact moving

    2 answers 1/6

    Source : quizlet.com

    Imagine the Universe!

    This site is intended for students age 14 and up, and for anyone interested in learning about our universe.

    Advanced Basic

    White Dwarf Stars

    A white dwarf is what stars like the Sun become after they have exhausted their nuclear fuel. Near the end of its nuclear burning stage, this type of star expels most of its outer material, creating a planetary nebula. Only the hot core of the star remains. This core becomes a very hot white dwarf, with a temperature exceeding 100,000 Kelvin. Unless it is accreting matter from a nearby star (see Cataclysmic Variables), the white dwarf cools down over the next billion years or so. Many nearby, young white dwarfs have been detected as sources of soft, or lower-energy, X-rays. Recently, soft X-ray and extreme ultraviolet observations have become a powerful tool in the study the composition and structure of the thin atmosphere of these stars.

    An Artist's conception of the evolution of our Sun (left) through the red giant stage (center) and onto a white dwarf (right).

    A typical white dwarf is half as massive as the Sun, yet only slightly bigger than Earth. An Earth-sized white dwarf has a density of 1 x 109 kg/m3. Earth itself has an average density of only 5.4 x 103 kg/m3. That means a white dwarf is 200,000 times as dense. This makes white dwarfs one of the densest collections of matter, surpassed only by neutron stars.

    What's inside a white dwarf?

    Because a white dwarf is not able to create internal pressure (e.g. from the release of energy from fusion, because fusion has ceased), gravity compacts the matter inward until even the electrons that compose a white dwarf's atoms are smashed together. In normal circumstances, identical electrons (those with the same "spin") are not allowed to occupy the same energy level. Since there are only two ways an electron can spin, only two electrons can occupy a single energy level. This is what's known in physics as the Pauli Exclusion Principle. In a normal gas, this isn't a problem because there aren't enough electrons floating around to fill up all the energy levels completely. But in a white dwarf, the density is much higher, and all of the electrons are much closer together. This is referred to as a "degenerate" gas, meaning that all the energy levels in its atoms are filled up with electrons. For gravity to compress the white dwarf further, it must force electrons where they cannot go. Once a star is degenerate, gravity cannot compress it any more, because quantum mechanics dictates that there is no more available space to be taken up. So our white dwarf survives, not by internal fusion, but by quantum mechanical principles that prevent its complete collapse.

    Degenerate matter has other unusual properties. For example, the more massive a white dwarf is, the smaller it is. This is because the more mass a white dwarf has, the more its electrons must squeeze together to maintain enough outward pressure to support the extra mass. However, there is a limit on the amount of mass a white dwarf can have. Subrahmanyan Chandrasekhar discovered this limit to be 1.4 times the mass of the Sun. This is appropriately known as the "Chandrasekhar limit."

    With a surface gravity of 100,000 times that of Earth, the atmosphere of a white dwarf is very strange. The heavier atoms in its atmosphere sink, and the lighter ones remain at the surface. Some white dwarfs have almost pure hydrogen or helium atmospheres, the lightest of elements. Also, gravity pulls the atmosphere close around it in a very thin layer. If this occurred on Earth, the top of the atmosphere would be below the tops of skyscrapers.

    Scientists hypothesize that there is a crust 50 km thick below the atmosphere of many white dwarfs. At the bottom of this crust is a crystalline lattice of carbon and oxygen atoms. Since a diamond is just crystallized carbon, one might make the comparison between a cool carbon/oxygen white dwarf and a diamond.

    Last Modified: December 2010

    Additional Links

    Quiz me about this topic

    Cool fact about this topic

    Try this!

    FAQs on white dwarfs and other stars

    Introductory level article on this topic.

    Give me additional resources

    Related Topics

    Cataclysmic Variables

    For Educators

    NCTM & NSES Standards

    The Life Cycle of Stars booklet

    Show me related lesson plans

    Source : imagine.gsfc.nasa.gov

    White Dwarfs Facts, Information and Photos

    Find out more about the Solar System's aging stars.

    PHOTOGRAPH COURTESY NASA/TOD STROHMAYER (GSFC)/DANA BERRY (CHANDRA X-RAY OBSERVATORY)

    SCIENCEREFERENCE

    White Dwarfs

    Find out more about the Solar System's aging stars.

    4 MIN READ

    When they reach the end of their long evolutions, smaller stars—those up to eight times as massive as our own sun—typically become white dwarfs.

    These ancient stars are incredibly dense. A teaspoonful of their matter would weigh as much on Earth as an elephant—5.5 tons. White dwarfs typically have a radius just .01 times that of our own sun, but their mass is about the same.

    Stars like our sun fuse hydrogen in their cores into helium. White dwarfs are stars that have burned up all of the hydrogen they once used as nuclear fuel.

    Fusion in a star's core produces heat and outward pressure, but this pressure is kept in balance by the inward push of gravity generated by a star's mass. When the hydrogen used as fuel vanishes, and fusion slows, gravity causes the star to collapse in on itself.

    Red Giants

    As the star condenses and compacts, it heats up even further, burning the last of its hydrogen and causing the star's outer layers to expand outward. At this stage, the star becomes a large red giant.

    Because a red giant is so large, its heat spreads out and the surface temperatures are predominantly cool, but its core remains red-hot. Red giants exist for only a short time—perhaps just a billion years–compared with the ten billion the same star may already have spent burning hydrogen like our own sun.

    The brightest star in the nighttime sky, Sirius, or the Dog Star, greatly outshines its white dwarf companion, Sirius B. At 8.6 light-years away, Sirius B is the nearest known white dwarf star to Earth.

    PHOTOGRAPH COURTESY NASA/ESA/H. BOND (STSCL)/M. BARSTOW (UNIVERSITY OF LEICESTER)

    Red giants are hot enough to turn the helium at their core, which was made by fusing hydrogen, into heavy elements like carbon. But most stars are not massive enough to create the pressures and heat necessary to burn heavy elements, so fusion and heat production stop.

    Further Incarnations

    Such stars eventually blow off the material of their outer layers, which creates an expanding shell of gas called a planetary nebula. Within this nebula, the hot core of the star remains—crushed to high density by gravity—as a white dwarf with temperatures over 180,000 degrees Fahrenheit (100,000 degrees Celsius).

    Eventually—over tens or even hundreds of billions of years—a white dwarf cools until it becomes a black dwarf, which emits no energy. Because the universe's oldest stars are only 10 billion to 20 billion years old there are no known black dwarfs—yet.

    Estimating how long white dwarfs have been cooling can help astronomers learn much about the age of the universe.

    Ancient white dwarf stars shine in the Milky Way galaxy. Stars like our sun fuse hydrogen in their cores into helium. White dwarfs are stars that have burned up all of the hydrogen they once used as nuclear fuel.

    PHOTOGRAPH COURTESY HUBBLESITE

    But not all white dwarfs will spend many millennia cooling their heels. Those in a binary star system may have a strong enough gravitational pull to gather in material from a neighboring star. When a white dwarf takes on enough mass in this manner it reaches a level called the chandrasekhar limit. At this point the pressure at its center will become so great that runaway fusion occurs and the star will detonate in a thermonuclear supernova.

    Source : www.nationalgeographic.com

    Do you want to see answer or more ?
    James 8 day ago
    4

    Guys, does anyone know the answer?

    Click For Answer