They can be. Stars are very hot and can emit harmful amounts of radiation. At the same time, without stars there would be no life.
ultraviolet radiation
Our sun emits mostly visible and ultra-violet radiation
Electromagnetic radiation is the primary solar radiation, which ranges from UV through the visible spectrum into the infrared (IR), including long radio waves.
They ARE gas - or more accurately plasma. They do though emit vast quantities of dust (condensed atoms and molecules of elements they have formed) and gas, along with subatomic particles and a great swathe of the electromagnetic radiation spectrum. The actual materials and radiation depend on the star itself, and its stage in life.
All forms.
Optical light
stars
Gamma rays
They can be. Stars are very hot and can emit harmful amounts of radiation. At the same time, without stars there would be no life.
Pulsars are highly magnetized, rotating neutron stars that emit a beam of electromagnetic radiation
Any material will emit blackbody radiation at any temperature. Lithium 6 will never emit ionizing radiation.
ultraviolet radiation
They do not! Most gases do not emit radiation.
Light waves do not emit radiation, light waves are radiation.
Then it will not emit any more radiation - except that it will eventually re-emit any radiation it receives, especially the cosmic background radiation.Then it will not emit any more radiation - except that it will eventually re-emit any radiation it receives, especially the cosmic background radiation.Then it will not emit any more radiation - except that it will eventually re-emit any radiation it receives, especially the cosmic background radiation.Then it will not emit any more radiation - except that it will eventually re-emit any radiation it receives, especially the cosmic background radiation.
If a neutron star's rotational period is fast enough to produce jets (A pulsar), said jets will emit radio waves, with faster periods emitting higher frequency radiation as well as the jets themselves emitting synchrotron radiation. Also, unless the neutron star were 0K, it will emit thermal radiation However, as far as a neutron star that isn't a pulsar, nobody knows if they emit anything but thermal radiation.