Telescopes

"I logged onto WikiAnswers, went directly to the Astronomy category, and immediately

chanced upon a new question that challenged: 'Use refracting telescope in a sentence' . "

The reflective telescope was invented by Isaac Newton in 1668. He designed a reflecting telescope with a curved mirror that resolved some of the issues associated with the refracting telescopes of the time.

The Hubble Space Telescope has seen Earth. While its primary function is to observe celestial objects in deep space, the telescope has also been pointed towards Earth for calibration and testing purposes.

The mirror in a telescope is a concave mirror. That shape redirects all the light coming from a distant object that hits the mirror into a focusing lens. The mirror may be as small as several inches or many feet in diameter and it concentrates the light so it can be focused by a small eyepiece that may be only a fraction of an inch in diameter. The mirror serves the same purpose as a large lens in a refractive telescope. It takes a large cross section of light and focuses it into the eyepiece of the telescope but it does it by reflection rather than refraction. The reflective mirror is preferred over a lens for several reasons. The light reflected by a good quality silvered mirror loses very little of its intensity. Light passing through a lens loses intensity each time it passes through a glass surface and it must pass through 2 surfaces of a lens. The mirror bends the light one time and a lens bends it twice. The more times you bend light, the more chance you have to introduce distortion because of imperfections of the surface. If the glass of a lens is not ultra pure and without imperfection, the light is further distorted. The quality of glass in a mirror does not affect the light because the light does not pass through the mirror because the light is reflected off the first surface. When very large telescopes are involved, a refraction lens would weigh many times what the reflective mirror weighs.

"Magnitude" is not a term that's usually used to describe a telescope, although

it's commonly used to describe the objects the telescope observes.

Down below this answer, we've added three links that will take you to sites that are

packed full of information on the Hubble Space Telescope. If the test is tomorrow,

then you probably ought to get cracking.

Both types of telescope collect and focus electromagnetic radiation for observational purposes, the difference is their band of observed frequencies. Radio telescopes are used for the radio frequencies ( ~3km - ~30cm) while optical telescopes are used for frequencies closer to visible light ( ~0.7μm - ~0.4μm). Optical telescopes may also be able to detect infrared and ultraviolet light.

With a telescope, you can observe celestial objects such as planets, stars, galaxies, and nebulae. Telescopes allow you to see these objects in greater detail and can also be used for stargazing, astrophotography, and scientific research.

If you had a telescope on a planet 3000 light years away and zoomed in on Earth, you would see the Earth as it was 3000 years ago. Due to the time it takes for light to travel, you would not be seeing Earth in real-time, but rather how it appeared 3000 years in the past.

You can't do much better than nineplanets.org - See related link

To calculate the magnification power with a 30 mm eyepiece, you need to divide the focal length of the telescope by the focal length of the eyepiece. For example, if the telescope has a focal length of 600 mm and you use a 30 mm eyepiece, the magnification would be 20x (600 mm / 30 mm = 20x).

No. Well, if you try to walk on one, you'll fall through, and that would hurt......

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Another contributor added:

Not unless one falls on you.

Radio telescopes don't transmit anything. They are super-sensitive receivers, designed to

pick up the faint whispers of radio signals coming to earth from elsewhere in the universe.

Your cellphone exposes you to more radiation than the largest radio telescope in the world does.

The biggest telescopes are reflecting - instead of a main lens, they have a main mirror. Above a certain size, it is no longer feasible, or at least practical, to use lenses.

The biggest telescopes are reflecting - instead of a main lens, they have a main mirror. Above a certain size, it is no longer feasible, or at least practical, to use lenses.

The biggest telescopes are reflecting - instead of a main lens, they have a main mirror. Above a certain size, it is no longer feasible, or at least practical, to use lenses.

The biggest telescopes are reflecting - instead of a main lens, they have a main mirror. Above a certain size, it is no longer feasible, or at least practical, to use lenses.

A telescoping time line allows for a visual representation of events occurring over different time frames with varying levels of detail, making it easier to understand chronological relationships and patterns. It helps organize complex information in a structured format, enabling users to navigate and comprehend historical or project-related data more efficiently.

The magnification of a telescope is the ratio of the effective focal length of the objective to the focal length of the eyepiece. For example, a small telescope's objective may have a focal length of 800mm. When an eyepiece with a focal length of 25mm is used, the magnification is 800/25 = 32.

The term "effective focal length" refers to the focal length of the objective as affected by any "focal extender". Many telescopes are designed to have a short total size, but high power, by "folding" the optical path. A mirror-type objective with a focal length of perhaps 800mm is coupled with a smaller curved mirror that intercepts the last 200mm and extends it to 800mm, a 4x extension, so that the effective focal length of that objective is 3200mm. Use that with a 25mm eyepiece and the magnification is 3200/25 = 128.

By the way, if a telescope is smaller than you are, it is seldom much use to view using a magnification greater than 50 to 100. Most objects are best viewed at relatively low powers such as 30 or so.

The Hubble Space Telescope has provided invaluable data on various bodies in our solar system, leading to a deeper understanding of their composition, behavior, and interactions. By capturing high-resolution images and studying the dynamics of celestial bodies, the Hubble telescope continues to refine and enhance our current model of the solar system.

A pair of mirrors are used in telescopes to make things appear bigger.

All total Theres been three Mir, Skylab and the ISS. Mir and Skylab burned up so onlt the ISS is up there

HST's Near-Infrared Camera/Multi-Object Spectrometer(NICMOS), installed on Servicing Mission 2 in 1997, and repaired during Servicing Mission 3A, was installed specifically to observe the infrared spectrum.

The James Webb Space Telescope (formerly the Next Generation Space Telescope), currently in final design reviews (the final step prior to manufacturing and testing) is designed as an outer orbit (past the Moon) infrared space telescope. The technology involved in such a device has caused a few delays, as the temperatures at that distance are much colder than in Earth orbit, and present different challenges for a device that must respond to precise commands, as well as one that can't be repaired.

The Hubble Space Telescope was launched on April 24, 1990. It has provided stunning images of the universe, helped scientists make numerous discoveries, and significantly advanced our understanding of astronomy and astrophysics.

A telescope design that has a hole in the center of the main mirror is called a "Cassegrain telescope." This design uses a secondary mirror to reflect the light back through the hole in the primary mirror to the eyepiece or sensor, allowing for a more compact design and longer focal length.

The focal length of the telescope's mirror can be calculated using the formula: Telescope focal length = Eyepiece focal length × Magnification = 26 mm × 70x = 1820 mm Therefore, the focal length of the telescope's mirror would be 1820 mm.

Having the Chandra X-ray Observatory in space allows it to capture high-energy X-rays from celestial sources without the Earth's atmosphere absorbing them. X-rays cannot penetrate the Earth's atmosphere, so having Chandra in space ensures that it can observe these energetic phenomena clearly and accurately. Additionally, being above the Earth's atmosphere provides a stable observing platform with minimal interference from factors like weather or light pollution.

Chandra X-ray Observatory detects X-rays, which are a type of electromagnetic wave with higher energy and shorter wavelength than visible light. X-rays are emitted by extremely hot and high-energy objects in the universe, such as black holes, neutron stars, and supernova remnants.

1. Hubble Space Telescope - it has been operational since 1990 and has provided numerous groundbreaking discoveries in astronomy.
2. Chandra X-ray Observatory - it has been studying the universe in X-ray wavelengths since 1999, helping to uncover high-energy phenomena.
3. Fermi Gamma-ray Space Telescope - launched in 2008, it observes the universe in gamma-ray wavelengths, enabling the study of extreme astrophysical processes.