Dust grains tend to emit radio signals with wavelengths around their own size. This fact allows us to study the types of dust being formed in early planetary systems.
The Sound of Creation
The cosmic microwave background can be converted to sound, just as a radio converts radio waves to sound. The result is the sound of the big bang.
What’s Cooking
Perytons are short bursts of radio waves detected by the Parkes radio telescope. They may be caused by astronomers hungry for a quick dinner.
Messages From Home
There’s something strange about fast radio bursts, but they are not a message from aliens.
That Escalated Quickly
Astronomers have observed a fast radio burst originating from 5.5 billion light years away.
Radio Jupiter
In the visible spectrum, Jupiter is a bright, star-like point in the night sky. Viewing it with the naked eye, it would be easy to confuse it with a star except for the fact that it doesn’t twinkle. At radio frequencies Jupiter appears very different. It doesn’t have a simple round shape, for example, and it is extraordinarily bright. So bright that it can outshine the Sun at some radio frequencies.
DRAGNs in the Sky
A radio galaxy is a galaxy that emits large amounts of radio waves. They were first discovered in the 1950s, but it wasn’t until the 1960s when a technique known as aperture synthesis was developed that we could resolve the distribution of radio emissions within a radio galaxy. It then became clear that many radio galaxies had a double-lobed structure emanating from a galactic core. It was suggested that these Double Radio Sources Associated with Galactic Nuclei be known a DRAGNs, though the term has never really caught on.
Low Down on the Radio
Most radio telescopes have a traditional dish shape, such as Arecibo or Parkes. But there are other forms a radio telescope can take, for example the radio antenna on your car. You might not think of your car radio antenna as a telescope, but in a way it is.
A Distant Noise
A while back I wrote about a phenomena known as fast radio bursts (FRBs). These short bursts of radio energy have been a bit of a puzzle. On the one hand they they have all the appearance of being astronomical in nature. For one thing, the frequencies of the signal are spread out so that higher frequencies arrive before lower ones. This is known as dispersion, and is an indicator having traveled through the interstellar medium. On the other hand, the signals are unusually strong, and their short duration is similar to radio interference from sources on Earth. They’ve also only been detected at one radio telescope (the Parkes radio telescope in Australia). That is, until now.