What are three NEW ways in which astronomers are looking out into the Universe????

Question

What new ways do astronomers use to look into outer space??

Answer 1

Radio wave astronomy;

These types of radiation have the lowest frequencies (longest wavelengths) and are mostly emitted by gases with strong magnetic fields. The strongest radio sources are dead stars which have collapsed and squeezed their magnetic fields; the regions around black holes where matter and magnetic fields are crushed to high density; and the plasma spat out of some galaxies, which isn't dense but has strong magnetic fields.

To receive this radiation you need a radio receiver or antenna, often with a big metal dish to reflect and focus the radio waves. at lower frequencies the atmosphere is mostly transparent to radio waves, and you can observe at any time. The main restriction is to be isolated from artificial radio sources, like mbile phones and microwave ovens. At shorter wavelengths (millimetre waves) water vapour causes a lot of absorption, so the telescope needs to be at a high altitude site with little water vapour.

Ultra-violet and infared

This is the radiation emitted by any object, regardless of whether it has strong magnetic fields or not. Objects at a few thousand degrees C emit mostly optical (visible to our eyes) and ultraviolet light. Objects at plus or minus a few hundred degrees C emit mostly infrared light. The bright sources at these wavelengths are dust, gas clouds and stars (either individually or grouped into clusters or galaxies). Big hot stars emit mostly ultraviolet, small cool stars emit mostly infrared, and medium stars emit mostly optical. This is why our eyes detect optical light: we need to see the light from our medium size star.

Ultraviolet, optical and infrared radiation is detected with a charge-coupled device (CCD): a small electrical chip that registers infalling light. CCDs are also used in digital cameras, video cameras etc., although astronomical versions are sensitive to much lower light levels. To reflect and focus the light you need big mirrors. For optical and some infrared light the atmosphere is transparent, while other infrared light is absorbed by water vapour. However the atmospher makes images blurry, so you want to get above as much of it as possible by putting your telescope on a mountain (or in space, if you have a big enough budget). Most ultraviolet light is completely blocked by the atmosphere, and can only be observed from space

Xrays And Gamma Rays

This is the shortest wavelength, highest frequency radiation. It is generally emitted by the very hottest, most energetic gases in the universe. This includes the material falling into black holes, and the explosions of the most massive stars.

This type of radiation is completely blocked by the earth's atmosphere, and must be observed from satellites in space. Some satellites carry specialized CCDs to detect X-rays, while other satellites have proportional counters: big lumps of crystal or gas that absorb an incoming ray and release a charge which flows into an electrical circuit. X-rays and gamma rays don't reflect well off mirrors. Some satellites focus on a region of the sky by blocking out the other regions, while others have mirrors that deflect light by only a small angle.

Non electromagnetic astronomy

Objects in space, including stars, give off particles as well as radiation. Exploding stars release subatomic particles called neutrinos. Particles can be detected directly by satellites in space or indirectly from the ground by looking at the energy they release when they enter the earth's atmosphere. While radiation travels in a nearly straight line, particles get bent around and deflected by various processes. We can't say where a particular particle came from, and use this information to map out sources in the sky. We can infer the total amount of particles which reach the vicinity of the earth.

There are also gravity waves: very small ripples in space itself which are predicted by Einstein's theory of relativity. If they exist, they would be generated by interactions among the most dense objects, such as the collision of two collapsed dead stars. No gravity waves have yet been observed, but there are efforts to make the first detection. A gravity wave compresses and expands space slightly, so the observatories look for changes in the separation of test masses.

Answer 2

We now use space telescopes and also we are not confines to the visible part of the electromagnetic spectrum, we now use the radio, microwave, gamma, infrared and UV bands to probe different areas of  interest