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Parallax
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Describe Two ways scientists calculate the age of the universe?
by using the distance from Earth to various galaxies and by calculating the ages of old, nearby stars.
How do you measure distances to astronomical objects?
For distant objects, astronomers use the units of "light years" and "parsecs". Several different methods are used to measure the distances. There is a series of yardsticks each one calibrated using the previous one. Here are some of the main methods used: The first measures the distance to Venus by using parallax on a transit. Venus is observed crossing the Sun simultaneously from two different places on Earth a known distance apart, and triangulation gives the distance. From that the diameter of the Earth's orbit is calculated exactly using Kepler's laws and the orbit model. Nowadays we can also measure the distance to Venus using radar signals. Next is the parallax of nearby stars, which is done by measuring the change in position of a star against the background of distant stars as the Earth moves round the Sun. Bessel did this first in the 19th century using the nearby star 61 Cygni. It's a method that extends to about 1000 light years. That was when we discovered how unimaginably far away the stars are, and it confirmed the heliocentric theory that the Earth orbits the Sun. Within 1000 light years there are several Cepheid variable stars like Delta Cephei that give away their distance because the period of variation depends on their absolute magnitude in a relationship discovered by Henrietta Swan Leavitt. This method can then be used to measure the distance to nearby galaxies if Cepheid variables can be found in them. Another possible method involves estimating a star's luminosity. There is a relationship between a star's color (spectral type to be more precise) and its luminosity (real brightness). This is the Hertzsprung-Russell diagram. We can get an estimate of a star's distance by comparing its observed apparent brightness with its estimated luminosity. However this is not a good method because there are very many giant stars that are much brighter than their temperature would indicate, and these obviously give wrong answers for the distance. At larger distances the distances to galaxies is measured by the Red Shift using the Hubble constant. Edwin Hubble showed that the shift in the spectrum of a galaxy towards the long wavelength end of the spectrum depends on its distance. By these means we know how far it is to the objects in the Universe.
Who measured the size of the earth using a shadow stick and knowing the distance between two cities?
Eratosthenes of Cyrene 3rd century
What is an advantage of using parallax rather than the Doppler effect to determine star distance?
Parallax is more accurate for stars that are very far away.
Would a moon constellation map be helpful on the moon?
Using a star map could potentially be useful as we used the stars to navigate in the times before advanced technology. Since the distance between the Earth and the moon is tiny compared to the distance between stars the constellations you see from the moon are exactly the same ones you see from Earth.
What ways can you measure th distance to nearby stars?
You can measure it by using absolute magnitude.
The distances to nearby stars can be measured by using . a. absolute magnitude c. color b. temperature d. parallax?
preallax
What are the steps when examining distance determination?
The answer depends on what distance is being determined: the distance to stars using parallax, the distance to aircraft using radar, the distance from one city to another partway around the earth, the distance between two nearby objects.
Describe Two ways scientists calculate the age of the universe?
by using the distance from Earth to various galaxies and by calculating the ages of old, nearby stars.
What is a dekameter best measured for using which distance?
e
The mass of stars is measured using observations of?
their orbits in binary systems
If the 1st 2nd and 3rd dimensions can be measured in distance units can the 4th dimension or time be measured using the same units?
No - because time is measured in seconds, not linear distance.
Three units used to measure distance to stars?
The nearer stars are measured by triangulation using the radius of the Earth's orbit as the basic yardstick. Friedrich Bessel discovered parallax in 1838, the slight movement of a star against the background of more distant stars caused when the Earth orbits around the Sun. He picked out a star that he suspected was close, called 61 Cygni, and found that it was at a distance of ten light-years. This method is used for stars out to about 200-300 light years.
How will distance be measured in the 2010 Olympics?
Using high tech computers
What objects are measured using the metric system?
Weight,distance,& volume
How can distance to stars be measured?
Distances of stars and objects in space can be measured by light years. Edit: This is a big question. The problem of measuring distance in astronomy has gradually been improved over many years. If you just mean stars within our Galaxy, the nearest ones can be measured using "parallax". The stars called "Cepheid variables" are very useful for bigger distances. The periods over which their brightness varies is linked to their "absolute magnitude" ( how luminous they really are). So their "apparent magnitude" (how bright they seem) gives a good guide to their distance. Spectroscopy is very useful too, because it gives us a good idea of how bright a star really is. Again the distance can be estimated by comparing the absolute and apparent magnitudes.
how to convert radius into meters?
That depends on the units the radius is measured in. Radius is a distance and can be measured using any unit of length.
