What determines the age and temperature of a star?

What determines the age and temperature of a star?

By measuring both the luminosity of a star, which is its brightness relative to the brightness of our sun, and the color spectrum of the star, which represents the surface temperature of the star and the rate at which it is burning its nuclear fuel, scientists are now able to estimate the age of the stars of the …

How do you determine the age of a star in a cluster?

By placing the stars in a globular cluster on a Hertzprung-Russell diagram, astronomers can determine the cluster’s age by looking at the main sequence turnoff point and comparing it with models of stellar evolution.

What is the age of a star?

Most stars are between 1 billion and 10 billion years old. Some stars may even be close to 13.8 billion years old—the observed age of the universe.

How do we calculate the age of the oldest stars?

Astronomers can figure out the ages of some of the oldest stars in the Universe by studying globular clusters. A globular cluster is a dense collection of close to a million stars, all of which formed at roughly the same time. The density of stars near the center of a globular cluster is enormous.

What causes a star to age?

In general, the larger a star, the shorter its life, although all but the most massive stars live for billions of years. When a star has fused all the hydrogen in its core, nuclear reactions cease. Deprived of the energy production needed to support it, the core begins to collapse into itself and becomes much hotter.

What factors determine the lifespan of a star?

A star’s life expectancy depends on its mass. Generally, the more massive the star, the faster it burns up its fuel supply, and the shorter its life. The most massive stars can burn out and explode in a supernova after only a few million years of fusion.

How is the age of a galaxy determined?

One way that we can determine the age of a galaxy is to measure the ages of the stars in a galaxy. Since we have a pretty good understanding of how stars evolve, we can take a census of the stars in a galaxy and look at the distribution of star ages in that galaxy.

How do scientists calculate the age of the universe?

Astronomers estimate the age of the universe in two ways: 1) by looking for the oldest stars; and 2) by measuring the rate of expansion of the universe and extrapolating back to the Big Bang; just as crime detectives can trace the origin of a bullet from the holes in a wall.

What is the best way to estimate the age of a star cluster quizlet?

because all of a clusters’s stars were born at the same time, we can measure a cluster’s age by finding the main-sequence turnoff point on an H-R diagram of its stars. The cluster’s age is equal to the hydrogen-fusion lifetime of the hottest, most luminous stars that remain on the main sequence.

How old is the youngest star?

Age and distance

Title	Object	Data
Oldest star	HD 140283	14.5±0.8 billion years
Youngest	Stars are being formed constantly in the universe so it is impossible to tell which star is the youngest. For information on the properties of newly formed stars, see Protostar, Young stellar object and Star formation.

What is the oldest star age?

They made observations via the European Space Agency’s (ESA) (opens in new tab) Hipparcos satellite and estimated that HD140283 — or Methuselah as it’s commonly known — was a staggering 16 billion years old.

Do stars grow as they age?

Later, as the preponderance of atoms at the core becomes helium, stars like the Sun begin to fuse hydrogen along a spherical shell surrounding the core. This process causes the star to gradually grow in size, passing through the subgiant stage until it reaches the red-giant phase.

What is the death of a star called?

As they orbit each other, the smaller of the two stars gathers material from its larger companion. The dying days of a star can be explosively spectacular, creating some of the most energetic events in the Universe. Stars do explode, and when that happens they’re known as supernovae.

Do stars change as they age?

During the red giant phase, a main sequence star’s core collapses and burns helium into carbon. After about 100 million years, the helium runs out, and the star turns into a red supergiant.

What determines the temperature of a star?

Key Concepts. A star’s surface temperature can be determined from its spectrum. The Hertzsprung-Russell diagram sorts stars by luminosity and temperature. Most stars are on the main sequence of the Hertzsprung-Russell diagram.

How is the temperature of stars determined by?

To get a stellar temperature: Measure the brightness of a star through two filters and compare the ratio of red to blue light. Compare to the spectra of computer models of stellar spectra of different temperature and develop an accurate color-temperature relation.

What does star temperature depend on?

The surface temperature is determined by the luminosity and radius. The luminosity is governed by the central temperature. An increase in mass, increases the central temperature and greatly increases the luminosity. The radius also increases, but not by enough to compensate, so the surface temperature also rises.

How do stars get their temperature?

Stars do not get hot because of nuclear fusion, they become hot enough to sustain nuclear fusion and this process maintains their temperatures.