Radiation

From Slackerpedia Galactica

Radiation comes in various flavors. You have the Greeks and then the outcast.

These types are called ionizing radiation.

There is alpha which is very short ranged and unless you inhale, inject or ingest it is not normally that harmful. You can even protect yourself from alpha radiation with a sheet of paper. Exposure to alpha internally, where it can get at your DNA is BAD, Mmkay, don't do alpha radiation Mmkay. Alpha decay of nuclei is related to He nucleus formation.

Beta is next and has a bit more power than alpha and can cause damage such as surface burns. You need lead to protect you from this stuff. This form of radiation lead to the discovery of neutrinos.

Gamma comes next. Over exposure to this will cause you to become a big green hulk of a guy. Try to stay calm if exposed to this. Gamma radiation is VERY penetrating and causes really pretty nasty radiation illness. Various astronomical phenomena can cause gamma rays. In fact some of those gamma ray bursts are the most powerful explosions observed. For example neutron star-neutron star mergers, black hole-neutron star mergers, black hole mergers. If a gamma ray burst occurs close enough it could give all life on Earth a BAD day.

Now you have the outcast X-rays. Yes they are wearker than gamma rays but they will still give you a nasty case of radiation sickness if you get freaky in the x-ray machine. The first human produced x-rays were done by Willie Röntgen. He was just trying to see his wife nakkid while she was wearing clothes. (I made that last part up). X-rays are commonly produced various things like magnatars and certain other pulsars.

Wikipedia has a better discussion if you're interested, but that would mean you're not a Slacker.