By comparing the known luminosity of the latter to its observed brightness, the distance to the object can be computed using the inverse-square law. The advantage of using a GPS to get your distances is the fact that you don’t have to do anything at all. These are objects which belong to a class that has a known brightness.


The stars could offer a new way to measure distances to objects in the universe. They are also able to measure an approaching or receding object. Weighing yourself on a bathroom scale or measuring the distance between you and a friend are both very simple here on Earth. Most physical distance indicators are standard candles. Often a GPS unit will be used to measure the distance to the center of the green, but most are capable of picking out any spot that you choose.

The Properties of Distant Galaxies. The distance in the Hubble law must be defined so that if A and B are two distant galaxies seen by us in the same direction, and A and B are not too far from each other, then the difference in distances from us, D(A)-D(B), is the distance A would measure to B. By using “non-contact” ultrasonic sensors, distances can be measured without damage to the object. This section indicates, step by step, how to measure short distances, long distances, distances in tall vegetation and horizontal and vertical distances in steep sloping areas. So by measuring a quasar's X-ray and ultraviolet emission the scientists can estimate the absolute luminosity at ultraviolet wavelengths; in turn, this can be used to gauge the quasar's distance. Ultrasonic sensors can measure the distance to a wide range of objects regardless of shape, color or surface texture.

To measure distances in a field (for example the length and width of a field), a chain or a measuring tape is used. It can easily be seen, using basic trigonometry (try it! They’re easy to use and, in many cases, can be used in place of other traditional sensors when the environmental conditions … Astronomers Find New Way to Measure Cosmic Distances Cepheid stars in galaxies such as M81, shown here. ), provided p is small (which it is for all stars), that the distance D to the near star is given by 206265 AU / p, where AU is the astronomical unit mentioned above (i.e., the distance from the earth to the sun, 150 million km or 93 million miles), and p is the parallax angle measured in seconds of arc.