Frontiers of Science: Chiron: New Sibling of the Planets?


How exact is scientific research and exploration? We often think of it as being very precise and correct, yet in the first stages of most new discoveries this is not always the case. A good example is the unusual discovery made by astronomer Charles Kowal of the Hale Observatories on Palomar Mountain in California on October 18, 1977. On that date Mr. Kowal spotted an object on a photograph taken with the 48-inch Schmidt telescope. He determined that the object was orbiting the sun much like the other planets of the solar system.

After alerting other astronomers of his finding, events moved quickly. The very next day Mr. Kowal located the object again on another photograph. Shortly thereafter an astronomer at the University of Arizona found the object in photographs made October 11 and 12, after which a student at the California Institute of Technology photographed the same object November 3 and 4.

A quick calculation of its orbit then helped Mr. Kowal to locate the object on a photograph taken in 1952, while two other scientists identified it on photographs taken in 1943, 1941, 1936, and 1895. Indeed, on the 1941 photograph the object was even singled out and marked with an arrow. However, since it was Mr. Kowal who determined that the object was circling the sun, he was the one who earned the recognition of being its “discoverer.”

But how does this relate to the correctness of scientific discoveries? For one thing, when it was first discovered the object was thought to be circling the sun in an orbit located between Earth and Venus. Later investigations, however, proved it to be located between Saturn and Uranus. The time it takes the object to circle the sun was initially thought to be about nine months, so the object was given the name “Fast-Moving Object Kowal.” Subsequent data showed the correct time to be more like 50 years, so its name had to be changed to “Slow-Moving Object Kowal.” Also, early estimates of its size put its diameter at less than one mile; but now it is believed to have a diameter that may exceed 200 miles.

It is obvious from this example that our knowledge of the solar system and, indeed, of all of nature grows step by step from vague ideas to more correct descriptions. Consequently, everyone should be careful in judging the truthfulness of any new scientific discovery until as much data as possible has been collected and studied.

Another good example of this fact is the possible existence of rings around Neptune. Before the discovery of rings about Uranus, some scientists felt there was good reason to believe that Saturn was the only planet in our solar system that could have such rings. Some stated rather forcefully that Neptune could not possess any. Now, however, in light of the new evidence about Uranus, scientific speculation is running high that Neptune, too, may possess a system of these heavenly halos.

But to return to Object Kowal, what exactly is it? For various reasons scientists are tending to rule out its being a comet or an asteroid, and it is obviously not a moon of any planet. One possible classification is that of a “planetoid” or small planet. Leaning toward this designation, Mr. Kowal has suggested a more permanent name for his “object.” He proposes to call it “Chiron,” after one of the centaurs of Greek mythology. He also feels that there may be even more such objects in orbit about the sun, and that the classification “Centaurian planets” would be appropriate for all of them.

We shall just have to wait and see if this is a logical conclusion. It is safe to say that all the facts in the matter are still not in. Until they are, it is best not to pronounce a verdict. One thing we can be sure about, however, is that Object Kowal, as well as all other objects, is a part of a glorious heavenly plan of creation.

[photo] A reproduction of original photograph of October 18, 1977, that led astronomer Charles Kowal to identify object marked by an arrow as a “planetoid” that is circling sun. (Hale Observatories photo.)

[photo] Interior view of dome of 48″ Schmidt telescope with observer at guiding eyepiece of the instrument. (Hale Observatories photo.)

[photo] Exterior view of dome of 48″ Schmidt telescope of Hale Observatories on Mount Palomar used to take photograph that led to discovery of Object Kowal. (Hale Observatories photo.)

[illustration] A graphical reproduction of orbit and position of Chiron on Christmas Day, 1977.