Space Telescopes Planets that are orbiting stars that are far away creating fluctuations in the light that we see coming from the star. Astronomers can observe those planets by measuring the fluctuations of that light.
The invention of the telescope by Galileo Galilei in the early 1600s helped early scientists discover more planets. By using telescopes to observe the night sky, astronomers were able to see celestial objects more clearly and detect planets that were previously invisible to the naked eye.
As of October 2021, astronomers have discovered over 4,500 confirmed exoplanets. This number continues to grow rapidly as new telescopes and technology are developed to detect more of these planets outside of our solar system.
Several methods are used. In many cases - perhaps most cases - the planets are discovered due to their gravitational effect on the star. That is, the star "wobbles" due to the gravitational pull of nearby planets, especially if the planets are very massive (planets more massive, "heavier" in popular language, than Jupiter, are easiest to detect), and close to the star. In some very specific cases, the planet may go right in front of the star, and make it become slightly dimmer once every orbit.
What an excellent question. It appears you already realize that if you are talking about stars other than our sun, you are talking about stars that are many lightyears away from us, and not even powerful telescopes will easily detect planets orbiting around them. One thing that astronomers can sometimes detect is the slight wobble of distant stars as planets orbit around them. You might not realize that suns would move as a result of a planet's orbit. Imagine you and a friend holding on to the ends of a rope. If you begin to move in a circle, you will each feel the centripedal force pushing you outward. Neither of you would be able to stand perfectly still while the other circled with the rope. Another thing that astronomers can detect using very sensitive equipment is the slight reduction in brightness of a star when a planet's orbit brings the planet between us and its star. If this reduction in brightness is regular enough, it may be an indication that there is a planet in orbit.
Astronomers cannot locate extrasolar planets with telescopes because these planets are outside of our solar system and too far away for telescopes to directly observe. Instead, astronomers use indirect methods such as radial velocity and transit techniques to detect these distant planets.
Space Telescopes Planets that are orbiting stars that are far away creating fluctuations in the light that we see coming from the star. Astronomers can observe those planets by measuring the fluctuations of that light.
We currently have the ability only to detect large planets that are close to their parent star, but as the technology progresses, we will be able to detect smaller planets, and planets that are further away. Also, astronomers have found systems of planets, meaning stars that have more than 1 planet.
Astronomers use a variety of methods to detect objects in space, including telescopes that observe different wavelengths of light (such as visible, infrared, and radio waves), sensors that detect particles like cosmic rays and neutrinos, and gravitational wave detectors. They analyze the data collected from these observations to identify objects like stars, planets, galaxies, black holes, and more.
Astronomers use evidence such as the behavior of nearby stars and gas, as well as the bending of light around invisible objects, to detect the presence of black holes in space.
The discovery of additional planets was made possible by advancements in telescope technology, particularly the development of large ground-based telescopes and space telescopes like the Hubble Space Telescope. These telescopes allowed astronomers to observe distant planets more effectively and detect previously unknown planets orbiting other stars.
The invention of the telescope by Galileo Galilei in the early 1600s helped early scientists discover more planets. By using telescopes to observe the night sky, astronomers were able to see celestial objects more clearly and detect planets that were previously invisible to the naked eye.
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As of October 2021, astronomers have discovered over 4,500 confirmed exoplanets. This number continues to grow rapidly as new telescopes and technology are developed to detect more of these planets outside of our solar system.
Astronomers can use their eyes to study the stars. They can also use various telescopes that either refract, reflect, and detect exotic formations.
No planets have been officially recognised outside our galaxy, though more than 500 exoplanets have been identified outside our solar system. Our nearest galaxy is too far away to detect such planets, though we can assume that it will contain several millions of planets based on observations within our own galaxy.
It is possible that every galaxy has some planets. We just are starting to detect some planets in other galaxies.