As comets move close to the Sun, they develop tails of dust and ionized gas. Comets have two main tails, a dust tail and a plasma tail. The dust tail appears whitish-yellow because it is made up of tiny particles â about the size of particles of smoke â that reflect sunlight. Dust tails are typically between 1 and 10 million kilometers (about 600,000 to 6 million miles) long.
Hyperhidrosis, or excessive sweating, is a common disorder which produces a lot of unhappiness. An estimated 2-3% of Americans suffer from excessive sweating of the underarms (axillary hyperhidrosis) or of the palms and soles of the feet (palmoplantar hyperhidrosis). Underarm problems tend to start in late adolescence, while palm and sole sweating often begins earlier, around the age 13 (on the average). Untreated, these problems may continue throughout life. Sweating is embarrassing, it stains clothes, ruins romance, and complicates business and social interactions.
People usually tend to sweat more when the temperatures are warm, when they practice exercises or when being put in the response to some specific situations that make them angry, embarrassed, nervous or afraid. In fact, some of the common causes of sweaty hands can include stress, nervousness, anxiety and depression. People experiencing this condition are more likely to have overactive sweat glands . Excessive sweating of the palms can result in some certain types of infections including bacterial and fungal infections or even the irritation of the skin .