How are comets and asteroids different?

How are comets and asteroids different?

Asteroids are made up of metals and rocky material, while comets are made up of ice, dust and rocky material. Both asteroids and comets were formed early in the history of the solar system about 4.5 billion years ago. Asteroids formed much closer to the Sun, where it was too warm for ices to remain solid.

What is the sunshine vitamin?

Humans make 90 percent of our vitamin D naturally from sunlight exposure to our skin – specifically, from ultraviolet B exposure to the skin, which naturally initiates the conversion of cholesterol in the skin to vitamin D3.

When was the DH introduced?

On April 6, 1973, Ron Blomberg of the New York Yankees became the first designated hitter in Major League Baseball history, facing Boston Red Sox right-handed pitcher Luis Tiant in his first plate appearance. “Boomer” Blomberg was walked.

Is a bubble a solid liquid or gas?

Air bubbles as a man surfaces in a pool. A bubble is a globule of one substance in another, usually gas in a liquid. Due to the Marangoni effect, bubbles may remain intact when they reach the surface of the immersive substance.

Which president served in both world wars?

Dwight Eisenhower later served as US Army Chief of Staff and was elected President of the United States in 1952. Lt. Gen. James Gavin was a noted American airborne commander during World War II.

Can you get stung by a dead jellyfish?

Jellyfish can sting with their tentacles if they brush against you when you’re swimming in the ocean. You also can get stung if you step on a jellyfish, even a dead one. Usually, jellyfish stings will hurt, but are not emergencies.

How far is Mars from the Sun?

At its farthest distance (aphelion), Mars is 154 million miles (249 million km) from the sun. At its closest (perihelion), Mars is 128 million miles (206 million km) distant. On average, the distance to Mars from the sun is 141 million miles (228 million km).

Why are port holes round?

If portholes were designed with angles, this stress would tend to concentrate at those points and perhaps crack the skin. With round portholes such stress is evenly distributed around the holes, making it less likely for such cracks to occur.