A comet is the loose, icy body with a long, narrow orbit.
Comets are very small solar system body made mainly of ices mixed with smaller amounts of dust and rock. Most comets are not larger than a few kilometers across. The main body of the comet is called the nucleus, and it can contain water, methane, nitrogen and other ices. Their speeds vary depending on their orbits and where they are in it. The closer they are to the sun, the faster they are going.
Answer:
There are four different stages of sleep.
Stage 1 NREM
Explanation:
<em>The process of firmly falling asleep has four stages through which a person goes.</em>
<em>It goes from being awake over light sleep and falling firmly into sleeping.</em>
(STAGE 1)
This is a stage in which there are non-rapid movements of the eyes. In other words, it is a process of dreamless sleep. You enter this stage the moment you decide to sleep and shut your eyes. After several minutes, your body is in fact in the sleeping mode, but not entirely. This means that you can easily be woken up without being aware that you have slept.
Features:
- <em>You can easily awake</em>
- <em>Your may roll and they may be a little open</em>
- <em>The blood pressure and the temperature of the brain start to decrease </em>
- <em>You experience the natural human reflexes that the brain sends to assure that the place of your sleep is in a safe environment. By sending twitches to your muscles, your brain may awake your body for several seconds which comes in handy if you are tired and close to sleep on work or some dangerous place like a cliff for example.</em>
- <em>Your breading starts to slow down alongside with your pressure and temperature, and your heartbeats slow down.</em>