What can astronomical telescopes see?

The astronomical telescope can not be measured by how far it is. Astronomical telescopes are two concepts that distinguish the visible from the clear. What can astronomical telescopes see? Optical lens manufacturers xiaopian Shengli photoelectric chat with you.

Astronomical telescopes are visible, but they are just seen. They do not mean to see clearly. Even the ordinary astronomical telescope, you can see a large number of extragalactic galaxies, nebulae and other celestial bodies, and some of them are several billion, hundreds of billions of light years away. So, if you press your formulation alone, astronomical telescopes can see the universe.

To evaluate astronomical telescopes can not say how far they should be. It should be seen clearly. This index is measured by the angular distance, which is the minimum resolution angle.

The simplest criterion is that, under the same optical design, the greater the aperture of the telescope and the stronger the ability to collect light, the more distant and weaker the celestial body can be seen, the more you can see the details.

Further speaking, optical design, glass material and manufacturing process will affect the result. But for beginners, as long as remember not to pursue high rate, do not be said that I is a few hundred times the technology to see how far away, high rate is based on large caliber basis. Big caliber should be pursued, that is, the bigger the better the object lens is. And the combined ratio is the relative aperture index, i. e. the diameter / magnification of the objective lens. The bigger the value, the better.

The normal 5 centimeter or 8 centimeter refracting telescope usually observes the moon's ring, the Venus phase, the Martian polar cap, the Jupiter stripe and the Galileo, and the Saturn's ring, while Uranus and Neptune can only observe the moon, and see a point, and require high visibility and good technology. Pluto is impossible. If you want to find Pluto, you need at least 15 centimeters of telescope, and you have to go through the maximum brightness period of Pluto.

As for several major asteroids in the solar system, occasionally comets with relatively large brightness are seen to test the technology of observers.

There is no problem about the moon, craters, but every mountain is a bit too. You can tell some large craters, their structure and appearance. It is recommended to refer to books and magazines and websites to see other lovers' observations and photographs.

Another note: do not take pictures taken by professional organizations for reference. Ordinary telescopes are unlikely to achieve that effect. Recommend several books to familiarise with first, Cambridge astronomers guide, beautiful stars, astronomy lovers manual and so on.

The standard of evaluating telescope is not to see how far it is, but to see its limit magnitude. The astronomical telescopes commonly used by amateur astronomers have two kinds of refraction and reflection. The catadioptric type is too expensive.

Refracting telescope requires very high optical performance of objective glass, so the price will increase exponentially with the increase of the aperture of the objective lens. In contrast, large caliber reflector telescopes are much cheaper. Generally speaking, less than 1000 yuan can buy a 80mm refraction or a reflection of 114mm, 1000 to 2000 can buy a 150mm reflection, 2000 to 3000 can buy a 102 refraction, 3000 can buy a 150 refraction or 203 reflection. The most popular brands used by astronomers are Bo Guan, star Trent, Jinghua, and grand view. Buying telescopes can't be cheap. If you see the 150 reflector telescope on the Internet for 1000 yuan, you should consider it carefully.

In imaging, the image of the refracting telescope is sharp but color difference; the reflection telescope has no chromatic aberration, but there is a spherical aberration, and its field of view is smaller than the refracting telescope. Baidu encyclopedia can be inquired for details.

The direct use of telescopes to look at Nebula galaxies can only be seen in a mass of vaguely blurred objects, which are photographed by celestial photography, requiring long exposure. Human eyes can not see what color, because the nebula Galaxy light is too weak, the eye does not accumulate color function, but the film has, so the film can take the color of the celestial body, and human eyes generally can not see.

In addition to the need for telescopes, celestial photography requires equator, digital SLR, electric heel, guide star eyepiece and so on. In general, 2 lenses, a guide star, and a photo are needed. The whole set of equipment will cost tens of thousands of yuan, and technology is needed.