It was one of the first planets ever discovered outside the Solar System. It was discovered using the pulsar timing method , where the regular pulses of a pulsar are measured to determine if there is a planet causing variations in the data. In July the International Astronomical Union launched a process for giving proper names to certain exoplanets and their host stars. Phobetor is, in Ovid 's Metamorphoses , one of the thousand sons of Somnus Sleep who appears in dreams in the form of beasts.
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Update Aug. The tally of planets in our solar system would jump instantly to a dozen under a highly controversial new definition proposed by the International Astronomical Union IAU. That would make Caltech researcher Mike Brown, who found UB, formally the discoverer of the 12th planet. But he thinks it's a lousy idea. He applauded the committee's efforts but said the overall proposal is "a complete mess. Brown and other another expert said the proposal, to be put forth Wednesday at the IAU General Assembly meeting in Prague, is not logical.
For example, Brown said, it does not make sense to consider Ceres and Charon planets and not call our Moon which is bigger than both a planet. The definition, which basically says round objects orbiting stars will be called planets, is simple at first glance:.
Stern expects a consensus to form around the proposal. This is the only one that doesn't have big problems. Basri made a similar proposal to the IAU in , part of the long-running saga of failed attempts to define "planet. But the IAU draft resolution explaining the definition is more complex [ Read the Draft Resolution ], with caveats and suggestions and surprises that some astronomers think render the entire proposal unworkable. In particular, this aspect was criticized: A pair of round objects that orbit around a point in space that is outside both objects-meaning the center of gravity or barycenter is between the two planets in space as with Pluto and Charon -would be called double planets.
Alan Boss, a planet-formation theorist at the Carnegie Institution of Washington, called the deliniation arbitrary. Brown said there will likely be other similar pairings discovered, and it's even possible a "triple planet" would be found given this definition.
In response to the criticism, Binzel said it was important to distinguish between planets and satellites. He noted that barycenters are used to define and describe double stars and so the concept should apply to planets, too. Would one of these Jupiters be a planet, and the other a satellite? The barycenter criterion means that a pair of Jupiters would be a double planet. Asteroid Ceres , since it is round, would be considered a planet.
Interestingly, Ceres was called a planet when first discovered in , then reclassified. It is just miles in diameter, compared to 1, for Pluto and 7, for Earth. And if astronomers determine that asteroids Pallas, Vesta, and Hygeia are also round, "they will also have to be considered planets," said Owen Gingerich, an historian and astronomer emeritus at Harvard who led the committee.
The IAU proposal suggests but does not require that these be called dwarf planets. Pluto could also be considered a dwarf, which the IAU recommends as an informal label. Boss, along with Stern, was on an IAU committee of astronomers that failed to agree on a definition. After a year, the IAU disbanded that committee and formed the new one, which included the author Dava Sobel in an effort to bring new ideas to the process. Boss called their proposal "creative" and "detailed" but said it does not hang together as a cohesive argument.
Given all the nuances in the definition, a dozen other objects would be put on an IAU list of "candidate planets" which, upon further study, might bring the tally of planets in our solar system to Stern, the New Horizons mission leader, said there could be "hundreds and maybe a thousand" objects in our solar system that are at least as big as Pluto.
That's fine with him. You discover new things, you adapt to new facts. Brown, the discoverer of the potential 12th planet, said the basic definition is fine, but "the resolution itself is a complete mess. The resolution calls for a new IAU committee that would evaluate other candidate planets. Normally, that's a process that takes place in a scientific journal, Brown said.
He called the notion of an IAU gatekeeper "bizarre" and "really a bad idea. The IAU should make a definition, then it's up to scientists to go about their business" of deciding what objects fit the definition.
Someone has to officially bestow names, etc. It is just the way the system works. A 'no' vote puts us back where we were. Brown worries, however, that the vast majority of astronomers at the IAU meeting work in other fields, outside planetary science. Join our Space Forums to keep talking space on the latest missions, night sky and more!
And if you have a news tip, correction or comment, let us know at: community space. Please deactivate your ad blocker in order to see our subscription offer. The 12 planets under the newly proposed IAU definition. Planet sizes are shown to scale but their orbital distances are not to scale.
Eventually there would be hundreds as more round objects are found beyond Neptune. The asteroid Ceres , which is round, would be recast as a dwarf planet in the new scheme. Pluto would remain a planet and its moon Charon would be reclassified as a planet. Both would be called "plutons," however, to distinguish them from the eight "classical" planets.
A far-out Pluto-sized object known as UB would also be called a pluton. IAU members will vote on the proposal Thursday, Aug. Its fate is far from clear. So to recap: Pluto would be a planet and a pluton and also a dwarf. Boss was bothered by the lack of definitiveness on this and other points. Eventually the inventory of planets would soar. Nobody can yet say how the vote will go. Debate Forces New Definition.
Discovery Alert: New Planet — a Heavyweight, but Habitable?
They were both the first extrasolar planets and the first pulsar planets to be discovered; B and C in and A in A is the lowest-mass planet yet discovered by any observational technique, with somewhat less than twice the mass of Earth 's moon. The convention that arose for designating pulsars was that of using the letters PSR Pulsating Source of Radio followed by the pulsar's right ascension and degrees of declination. The modern convention prefixes the older numbers with a B meaning the coordinates are for the All new pulsars have a J indicating Pulsars that were discovered before tend to retain their B names rather than use their J names, but all pulsars have a J name that provides more precise coordinates of its location in the sky.
PSR B1257+12 C
Update Aug. The tally of planets in our solar system would jump instantly to a dozen under a highly controversial new definition proposed by the International Astronomical Union IAU. That would make Caltech researcher Mike Brown, who found UB, formally the discoverer of the 12th planet. But he thinks it's a lousy idea.
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