Richard Calantropio, age 12, of Brooklyn
What is a white dwarf star?
We are not surprised when a big bag of feathers weighs no more than a small brick; Brick material is more dense than loosely packed feathers. But imagine packing 20 tons of something into a single slo et That stuff would be 2000 times more dense than platinum. No such heavy material exists on earth. However, such dense stuff does exist in the white dwarf stars,
Our sun is an average sized star. There are giant stars that make it seem like a pigmy. There are also midget stars no bigger than sizeable planets. A few dozen of these white dwarf stars have been discovered as companions to bigger, brighter stars.. The most famous one is the companion of Sirius, the Dog Star. Naturally, this star is called the Pup.
The Pup was found while astronomers were unraveling the mystery of double stars. Careful checking showed that Sirius traveled.a wavy path. It took fifty years to show that the big star was making an orbit ‑ surely around some invisible companion. This work was completed in 1844.
Alvin Clark was a skilled lens grinder of Boston. In 1862 he finished a new 18 inch telescope lens for the University of Mississippi: Of course he peeked through it. What did he see? Clark got the very first view of the Dog Stars companion. Plans for that famous lens were upset by the War between the States. It now belongs to Northwestern University and is mounted at Dearborn. But nothing stopped the study of the new star.
The first data seemed most mysterious. The Pup's mass, or weight, was equal to 96 percent of the mass of the sun. Yet our sun gave off 340 times more light. Was the Pup less brilliant because it was cooler? Not at all' Its surface temperature was around 8,000 degrees Centigrade, some 2,000 degrees hotter than the face of the sun. Instead of being red hot, the new star was white hot,
The biggest surprise came with estimates of the new stars size. Its diameter is about 28,000 miles. Here is a star no bigger than the plant Uranus. There is room for a million earths in the sun. Imagine trying to pack 96 percent of the Bunts material into a space no bigger than five earth's The Pup star can do it. It may be small, but it is tremendously hot and heavy ‑ it is a white dwarf star,
Brick material is heavier than feathers because it. is more closely packed. But even in dense platinum there is space between molecules between. atoms and between the tiny particles of which atoms and molecules are made, Perhaps the Pup eliminates this kind of waste space. Certainly no space wasting molecules could exist in such hot dense materials. Perhaps all the electrons the outer shells of the atoms are stripped away, This way the smaller atomic particles could be more closely packed with less waste space between them, They could be jam‑packed so closely together that a thimbleful of the dense material would weigh 500 pounds.