unit 5 topic 4 Flashcards
who discovered Uranus and how?
sir William Herschel built a huge reflecting telescope and discovered the planet Uranus in 1773
where was the largest telescope built
it was built at the Yerkes Observatory near the end of the nineteenth century
what is interferometry? what does this technique do
the technique of using a number of telescopes in combination. When working together these telescopes can detect objects in space with better clarity and at greater distances than any current earth-based observatory
what is one interesting fact about the Hubble telescope
it makes one complete orbit of the earth every 95 min
why is the Hubble telescope so special how is it different from other telescopes on earth?
the instruments on the hubble consist of cameras and spectrometers. The images it records are transmitted to another satellite. Earth’s atmosphere neither blocks the radiation nor distorts the images that the telescope receives. this allows the Hubble telescope to record images that no other telescope on earth could
what is adaptive optics? and what is an example of something that uses adaptive optics?
The NTT ( New technology telescope) is called adaptive optics becuase computers control the image, and they are always adapting the mirror to changes in the earths atomosphere
what do the computers do in adaptive optics?
remove the clurred effect of the atmosphere
why do stars twinkle
stars twinkle because the motion of the earth atmosphere refracts their light randomly.
what is a galaxy?
is a grouping of millions or billions of stars, has and dust. it is held together by gravity.
why cant telescopes see the black hole?
they are invisible to telescopes, their existence is only known by an indirect method when celestial ,material comes close to a black hole it becomes very hot and very bright.
where do stars form?
in regions of space where there are huge accumulations of gas and dust called nebulae
how did intersellar matter form?
it makes up part fo the nebulae and originated from exploding stars.
Telescopes enables astronomers to see further into space and identify distant stars. The problem is how far are stars from the eath?
the answer to this question lies in two methods. Triangulation and Parallax are two ways to measure distances indirectly, on the ground, or in space.
what is triangulation
is based on the geometry of a triangle. By measuring the angles between the baseline and a target object you can determine the distance to that object.
what is parallax
is the apparent shidt in postiion of a nearby object when the object is viewed from two different places.
