X-rays from the Sun captured on NASA's telescopes
- physicsjudo
- Dec 24, 2014
- 1 min read
Image credit: NASA/JPL-Caltech/GSFC
NASA's telescopes have managed to capture striking images of our Sun, showing large outbursts of X-rays.
How much do you know about electromagnetic radiation (of which X-rays are a member)?
They are transverse waves caused by the perpendicular vibration and propagation of electric and magnetic fields. Recall Fleming's left and right hand rule, which gives a very good example of the perpendicularity of magnetic and electric fields.
So how are EM waves generated? All objects have internal energy, consisting of kinetic energy (temperature) and potential energy (state of matter). When thermal energy flows to the object, its kinetic energy and temperature will increase.
At low temperatures, the object will release long wavelength radiation such as microwaves, radiowaves and infrared radiation. Infrared radiation is what we detect as 'hotness', for example standing in front of a campfire.
When the object gets even hotter, it starts to release higher and higher frequency radiation, starting with visible light, then moving on to ultraviolet, x-rays and finally gamma radiation. The Sun, being the nuclear furnace that it is, is at blistering temperatures. It releases all the members of the EM spectrum, and with detectors on Earth, we are able to see them.
Long wave radiation are mostly harmless and pass easily into our atmosphere. Shortwave radiation are very harmful, but fortunately, they are stopped by the small particles that make up our atmosphere.
If you have read the entire post up to here, congratulations! I hope you have learnt something that you don't already know.
Comments