Radio

The simple answer would be to divide 500 billion by 120, which gives an answer of slightly over four billion. The reality might be different, however. Just because a civilization is broadcasting radio signals does not mean that we necessarily can detect those signals. The Milky Way galaxy is 200,000 light years across on its long axis (80,000 on its shorter axis) and there are some stars which are so far away that it would take tens of thousands, even a hundred thousand years for a radio message to reach the Earth, and the hypothetical broadcasting civilization might not have been broadcasting for that long. And even if they were broadcasting long enough, the signal strength might not be enough to allow us to separate it from the background noise. And we might not be listening on the same frequency on which they are broadcasting. Those are just the most immediate complications.

In order of increasing frequency: (i) radio waves. (ii) microwaves. (iii) infrared. (iv) visible light. (v) ultraviolet. hope this helps =)

1) Any object that emits radiation (because of its temperature) will emit in all wavelengths, including visible light, infrared, radio waves, ultra-violet, etc.

What changes is the proportion of each (which depends directly on the temperature).

2) The Earth's atmosphere is transparent to radio waves (meaning: it is easy to receive radio waves from space -- in general they are not blocked by the atmosphere).

3) It is easy to build a receiver that gives us the direction from which the radio waves are coming. We can draw maps of radio sources (the same way that taking pictures in visible light lets us draw maps of the visible stars).

Radioactive isotopes can be used in the study of metabolic pathways because they can be incorporated into specific molecules, allowing researchers to track the movement and transformation of these molecules within metabolic pathways. By measuring the radioactivity, scientists can gain insights into the speed and efficiency of various metabolic processes in cells.

The term "radio telescope" is used because it specifically refers to a type of telescope that is designed to detect radio frequencies emitted by celestial objects. The term "radioscope" may cause confusion as it could be interpreted as a device that visualizes radiation in general, not specifically radio waves.

All that is needed to receive a radio station is a crystal and wire (see crystal sets) or a diode and then some kind of ear phone. Your hand and the wire acted like a diode, and the amplifier the ear phone. There is not much to a simple crystal set that will receive a radio station. The diode action was created with a wire and a rusty razor blade by soldiers in WWII.

There are at least two reasons why identical radio telescopes may be built. A mundane reason would to save money by reusing the same design. But the reason why most identical systems are built (not to say that saving money by reusing the design isn't still a factor in these cases) is to construct a "very long baseline interferometer", a type of multiple telescope system that uses properties of electromagnetic radiation (wave interference) to simulate telescopes with much larger apertures. This method attains the angular resolution of the larger telescope, but not the signal sensitivity.

Quasars emit strong radio waves in addition to other forms of radiation like visible light. These radio emissions can be detected by radio telescopes, which is why quasars are sometimes colloquially referred to as "radio stars."

A radio reporter delivers news and stories through audio broadcasts, while a television reporter delivers news and stories through visual broadcasts. Radio reporters focus on creating compelling audio content, while television reporters need to be skilled in delivering information visually through video. Both roles require strong journalism skills and the ability to present information in a clear and engaging manner.

The distance between two radio telescopes is important for interferometry, a technique used to combine signals from multiple telescopes to improve resolution and sensitivity. By measuring the time delay between the signals received at each telescope, scientists can determine the distance between them and use this information to create detailed images of celestial objects.

Energy produced by air is either called Kinetic Energy or Sustainable Energy.

Willard Libby is credited with developing radiocarbon dating in the 1940s, for which he was awarded the Nobel Prize in Chemistry in 1960. The method revolutionized archaeology and other fields by allowing scientists to accurately determine the age of organic materials.

Frequency = (speed) divided by (wavelength) = (330) / (15) = 22 Hz.

"Poor" is really a woosy adjective.

If you're willing to express the size of the objective mirror in terms of wavelengths instead of

inches or meters or yards, then a radio telescope and an optical telescope with equal diameters

have equal resolving powers.

The familiar difference in their dimensions is simply the obvious consequence of the difference

in the wavelength of the signals they happen to be looking at. The shortest radio waves are

something like 2,000 times as long as the longest light waves.

Arecibo

Warm air near the surface rising due to lower density, cooling as it ascends, and then sinking back down again in a continuous cycle.

The question is not that straight-forward... For example Polonium releases a lot of radiation in alpha-particles, arguably most of all feasable elements, but the half-life of it's isotopes is rather short. Also, alpha particles won't do too much damage as they bounce off pretty much anything (as opposed to gamma, which need thick slabs of lead to be stopped).

There are also "evil" isotopes of non-radioactive elements, for example Niobium-95, which pretty much takes the cake in activity and it releases beta and gamma particles (ouch!), but with a half-life of 35 days it's not that much of a hazzard.

Also, Radon is kind of a nasty because it's a gas and it's actually not that rare. Long half-life, non-reactive, gaseous and quite present on the surface of the planet...

Radio waves are a type of electromagnetic radiation that are emitted by accelerating electric charges. When electrons within an antenna are oscillated or accelerated, they create electromagnetic waves at radio frequencies. These waves then propagate through space and can be received by devices like radios or antennas.

" RAY-dee-oh TELL-uh-skope"

That honour could be said to go to Karl Jansky (1905-1950). In 1932 he was working for the Bell Telephone labs on a project to identify possible sources of interference on shortwave radio links. While he was doing this he noticed a hiss in his radio receiver that would appear and peak once a day. His first thought was it was the Sun, however it kept sidereal time (that is it peaked 4 mins earlier each day), which suggested an astronomical source. He eventually identified the source as being in the constellation of Saggitarius. We now know that the radio hiss was coming from the centre of our galaxy. Bell were not interested in following up on his discovery so Jansky did not take it any further. But it was taken up by Grote Reber. He built a parabolic dish aerial, the sort most people associate with radio astronomy. Reber went on to create a radio map of the sky, so he was probably the first true radio astronomer.

The ionosphere is the layer responsible for enabling long-distance radio communication by reflecting radio waves back to Earth. Its charged particles interact with radio waves, bending and reflecting them to facilitate communication over long distances. Without the ionosphere, radio waves would continue into space, limiting long-distance communication possibilities.

A gas measuring tube is a laboratory glassware used for collecting and measuring the volume of gases produced during a chemical reaction. It helps in determining the amount of gas produced and studying the stoichiometry of the reaction.