This increases the chance that with the improvement in the equipment, terrestrial globes will also be discovered
Astronomers engaged in planet hunting made a very important discovery at the end of March - two planets whose size may be smaller than the size of the second largest planet in the solar system - Saturn. So far all the planets discovered so far (over thirty) have been at least the size of Jupiter. The existence of planets the size of Saturn shows that around many stars there are small planets in addition to the planets of the type of Jupiter.
Discoveries of planets the size of Saturn strengthens the theory that the planets were formed through an effect similar to a snowball that enlarges itself as it absorbs more and more material from the environment - that is, from the material found in the disk surrounding the young Saturn. The twenty-year-old theory predicts that there will be more small planets than large ones in any solar system, and this is the trend the researchers are starting to see in their data.
"It's like looking at a beach from a distance," explains Jeff Marcy from the University of California at Berkeley (who co-discovered it with Dr. Paul Butler from the Carnegie Institution. "At first we only see the big rocks - the planets bigger than Jupiter. Now we see the rocks (Planets the size of Saturn and smaller.) We currently do not have the ability to observe Earth-like planets, and therefore we have not yet seen the pebbles in the parable.
Jupiter alone is 3 times larger than Saturn. This leaves open the possibility that these may be Saturn stars in the making and not planets - these bodies are called brown dwarfs, and they are formed like stars through the collapse of gas clouds and not in the opposite direction as planets are formed. But now the researchers are more certain that these "Jupiters" are only the tip of the iceberg, and that there are many planets that can be discovered in those solar systems - and that their size is the size of Saturn or smaller.
Now we are convinced that we are seeing bodies formed from the disks of gas clouds such as those photographed by Hubble around many stars." says Marcy.
The astronomers did not observe the planets directly. They deduced their existence through calculations based on small fluctuations in the light rays, which are created as a result of the gravitational force that the mother sun exerts on a planet close to it.
One of the planets is in an orbit very close to its sun and orbits it in only three days (ie a year in his time terms). The average temperature there is 1,130 degrees Celsius.
The second planet is farther from its sun and completes its orbit in 75 days. The temperature in it is 830 degrees Celsius.
The following segment appeared in "Haaretz" by Tamara Traubman
Astronomers have discovered two new planets, the smallest of all the planets discovered so far outside the solar system. The discovery increases the chances of discovering Earth-sized worlds outside the solar system.
The astronomers were able to discover evidence of the existence of the two new planets with the help of the most powerful telescope on earth - "Kek" in Hawaii - and thanks to the refinement of the methods for discovering planets. Both planets orbit very close to their suns and the warm temperature rules out the possibility of familiar life forms existing there.
But team members Dr. Jeff Mercy of the University of California and Dr. Paul Butler of the Carnegie Institution, as well as other scientists, say the discovery heralds a new phase in the discovery of distant planets. All 30 distant planets discovered so far have been larger than Jupiter, the largest planet in our solar system.
Dr. Marcy, who discovered 21 of the known planets with his colleagues, added that "it seems that now it is only a question of time and the improvement of methods until worlds the size of the Earth are discovered."
The size of a planet is a fundamental factor in the possibility that life will develop on it. The bigger the planet, the greater its gravity. The enormous force of gravity in giant planets like Jupiter, rules out the possibility of familiar life forms developing there.
The astronomers did not observe the planets directly. They deduced their existence through calculations based on small fluctuations in the light rays, which are created as a result of the gravitational force that the mother sun exerts on a planet close to it.
One of the planets is in an orbit very close to its sun and orbits it in only three days (ie a year in his time terms). The average temperature there is 1,130 degrees Celsius.
The second planet is farther from its sun and completes its orbit in 75 days. The temperature in it is 830 degrees Celsius.
{Appeared in Haaretz newspaper, 31/3/2000}
Does the earth have twins?
Scientists have managed to discover distant planets smaller than Saturn. The meaning: It is possible that planets with conditions similar to Earth allow life to exist
"Star Hunter" scientists have discovered two planets smaller than Saturn, orbiting Saturn like the Sun. The discovery strengthens the hypothesis that there are stars in the universe with conditions like Earth's, and life may have developed in them.
So far, only the largest planets have been discovered from Jupiter, which is the largest planet in the solar system. On stars of this size, the chance of life developing is slim, because their conditions are completely different from Earth's.
Scientists have always assumed that smaller planets also exist, but the technical equipment at their disposal did not allow them to be discovered. "It's like looking at the beach from afar",
says Jeff Marcy of the University of California. "Before, we could only see large rocks, now we also notice stones." But scientists still don't have the instruments to detect Earth-sized stars. The difficulty in locating planets lies in the fact that they do not emit their own light like Saturn's stars.
The stars now discovered are slightly smaller than Saturn. One of them is 109 light years away from Earth, and the other is 117 light years away. However, the orbit of these stars around their suns is much faster than that of the Earth. The first orbits its sun in 75 days, while the second - in only three days. The assumption is that there is no life on these stars due to their proximity to their sun, as well as the assumption that due to their size they are mostly stars composed of gases without solids, such as Jupiter.
However, the discovery gives hope that stars with Earth-like conditions will soon be discovered.
