An exoplanet named HIP 11915b is being described by some astronomers as Jupiter's twin. This massive, oddly familiar world has just been spotted orbiting around an alien star.
Astronomers still hope to find twins of our planet as well as our entire solar system. At one time, many scientists believed that families of planets around other stars would largely resemble our own. However, with more than 1,000 alien worlds now discovered, astronomers have found solar systems form in a wide variety of formations.
"[T]he quest for an Earth 2.0, and for a complete Solar System 2.0, is one of the most exciting endeavors in astronomy. We are thrilled to be part of this cutting-edge research, made possible by the observational facilities provided by ESO," Jorge Melendez from the Universidade de São Paulo said.
The 142-inch telescope at the European Southern Observatory was used to examine a star much like our own sun. Using the High Accuracy Radial velocity Planet Searcher (Harps) instrument, astronomers discovered a planet much like our own behemoth of the solar system, Jupiter. This massive exoplanet is not only roughly the same size as Jupiter as well as approximately the same distance from its parent star, but the alien world also seems to have a similar composition to its "twin."
Oddly, the star HIP 11915 around which the exoplanet was found is also a near-twin of our own sun. Astronomers found that body has about the mass of our sun, contains roughly the same constituent materials and is roughly the same size as our parent star.
The easiest planets to detect are massive worlds orbiting close to their companion stars. This is due to the significant gravitational pull on their stars as well as the amount of light that can be blocked by the planet if its orbit is aligned with the Earth. However, these solar systems are thought to be unlikely places for life to develop and flourish. Some astronomers believe that the HIP 11915 system could contain smaller worlds, orbiting closer to their parent star.
"After two decades of hunting for exoplanets, we are finally beginning to see long-period gas giant planets similar to those in our own solar system thanks to the long-term stability of planet-hunting instruments like Harps," said Megan Bedell of the University of Chicago.
As additional exoplanets continue to be discovered by astronomers, more worlds like these, and perhaps like Earth, could be found in the far reaches of space.
Discovery of the twin of Jupiter was profiled in Astronomy & Astrophysics.