Any material objects which are under review, but out of reach have the final sizes, whether it be a tree in the field or the moon in the night sky. The question is in how it is correct to estimate them — the distance distorts idea of their true size. There are several techniques how to determine the size at distance.
It is required to you
- - theodolite;
- - roulette;
- - calculator;
- - range finder;
- - ruler.
Instruction
1. The most exact and fast way of determination of the size of an object at distance — by means of a range finder. Operation of this device is based on definition of time of reflection of a signal (active range finder) or calculation of distance to a subject of base and a parallactical corner.
2. Measure by a range finder distance to an object.
3. You hold before yourself a ruler in an outstretched arm and determine by it the size (height, width) of a subject in millimeters.
4. Increase the distance defined earlier by a range finder to a subject (in meters) by the subject size measured by a ruler (in millimeters) and divide this work into constant coefficient 6. The received value — the subject size in centimeters.
5. The method of determination of the sizes at distance based on a triangulation or otherwise - parallactical shift. Choose two points on areas from which the interesting subject is visible. The triangle which tops are two chosen points and the interesting subject turned out.
6. Measure by a theodolite distance between these two points (basis) and adjacent corners.
7. Calculate on the available corners and distance between two points two other parties of the triangle formed by a subject and points of observation. Using distance, calculate the sizes of the interesting subject of earlier provided scheme.
8. And, at last, sizes of celestial bodies. The sizes of stars determine by their luminosity and temperature. Increase Earth radius by a square root from the attitude of luminosity of a star towards luminosity of the Sun. Increase the received number by a square of the relation of temperature of the Sun to star temperature. The received size — the radius of the interesting star.
9. To a planetumnozhta distance to planets in kilometers on a corner under which this planet is visible and divide the sizes into 206265 — the size of 1 radian expressed in seconds. It is also diameter of the interesting planet. Dimension: distance - in kilometers, a corner - in seconds. The distance to the planet is calculated by a method, the similar way of determination of distance described above to a subject on Earth. For celestial bodies the concept of horizontal parallax is used (basis is Earth radius).