More like 41 L.Y. in order for it to be visible -- 41 million is farther than most of the galaxies in our local "neighborhood".
Also, for the solar system to be truly similar to our own, the scientists will have to find evidence of a planet imminently in danger of extinction from greenhouse gases due to the activities of its inhabitants ... ;^)
Jupiter-like planet orbits sun-like star 240 trillion miles away
06/14/2002
After more than a decade of searching, astronomers say they have identified a planetary system with a family resemblance to our own.
New evidence reveals a Jupiter-like planet orbiting a star like the sun in a path similar to Jupiter's, the researchers announced Thursday at a NASA news conference in Washington, D.C. The presence of that planet opens the possibility that an Earth-like planet could exist within the distant system.
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"For the first time, we've found a family of planets that has some similarity to our own solar system," said Geoffrey Marcy, an astronomer at the University of California, Berkeley.
Dr. Marcy conducted the planet search with Paul Butler, of the Carnegie Institution of Washington in Washington, D.C., and a team of other researchers.
Most planets outside our solar system, known as "extrasolar" planets, orbit close to their parent stars in eccentric ovals. And most of them have turned out to be hot balls of gas like Jupiter.
An outer planet in an orbit like Jupiter's is the one sign that a planetary system could support rocky, terrestrial planets like Earth, Dr. Butler said. The new planet satisfies that condition. It completes one orbit every 13 years, while Jupiter circles the sun in just less than 12. And its orbit is nearly circular, like Jupiter's.
Calculations by Greg Laughlin of the University of California, Santa Cruz, show that if there were an Earth-like planet in this system, it could survive in a stable orbit at the right distance from the star for moderate temperatures. Planets too close to the star would be too hot to support life.
While this system does not share all the qualities of the Earth's solar system, Dr. Butler says, "it could be classified as a first cousin."
The new planet is one of 15 introduced by Drs. Marcy and Butler on Thursday, bringing the total number of known extrasolar planets to more than 90. Its parent star, known as 55 Cancri, is relatively close to Earth in galactic terms, at 41 light-years (240 trillion miles) away. It is visible to the naked eye in the constellation Cancer. It is also orbited by at least two other planets. The first was discovered by Drs. Marcy and Butler in 1996, and the other was also announced Thursday.
Both of these planets orbit close to 55 Cancri and are more typical of most known extrasolar planets. The innermost planet is slightly smaller than Jupiter and darts around 55 Cancri in just 14.6 days. The middle planet is smaller but has a slightly wider orbit.
It would be far too hot for a terrestrial planet to form within the orbits of planets like these. But the existence of an outer planet with a Jupiter-length orbit creates a gap that leaves room for smaller planets to form from the rocks and dust that float around in such spaces.
Drs. Marcy and Butler expect that many other solar systems with Jupiter-like outer planets, like the one they described Thursday, will be found in coming years.
William Cochran, of the McDonald Observatory of the University of Texas at Austin, said he is "very confident that this is the first of a whole class of planets that will be coming out." The detection methods used to find the new planet would not be able to find an Earth-size planet, Dr. Cochran added, but "having outer Jupiters means there is room for inner Earth-like planets."
With current technology, signals of a planet's presence must be observed throughout its orbital course for it to be characterized, and so it has taken 13 years of observation for Drs. Marcy and Butler and their research team to be able to describe the planet.
They found the new planet by measuring the change in a star's motion as viewed from Earth. A planet will exhibit a gravitational tug on its star, causing a wobble in the star's orbit, shifting the color of light emitted by the star.
Future projects, such as NASA's Kepler mission, will use sophisticated optical telescopes to examine a large number of stars for signs of terrestrial planets.
E-mail sgoforth@dallasnews.com
NASA --> An artist's conception compares our solar system with the planetary system around 55 Cancri. The system has two planets orbiting close to a sun-like star, and a Jupiter-like planet that's about the same distance that Jupiter is from our sun. -->
41 million? Well, if we detect any intelligent life there it would have been as it was 41 million years ago. I'm sure they nuked themselves at least 40 million years ago. LOL
Typo, obviously, it wouldn't be visible to the naked eye at that distance.
