Thanks to the Hubble Space Telescope NASA and the ESA have discovered why to date the search for Earth-like planets has found their existence to be so rare. Scientists estimate that there are a mere 17 billion possible Earth-like planets in the universe. To date Keppler has found only a small number; 2740 planet candidates, 231 of which have been confirmed.
The pollution or space debris that has been discovered has been detected whirling around white dwarfs. It is believed that it is left over debris from asteroid belts formed from the tidal forces of the white dwarfs. Yet another discovery came from this debris and the elements that make it up. In the Haydes cluster evidence of silicon as well as low levels of carbon, Earth-like materials, were found thanks to a study by Jay Farihi of the University of Cambridge. Disappointed by the low number of planets located Farihi changed where he was observing to follow instead the retired clusters and now this has provided knowledge of where to actually spy Earth-like planets as well given a clue as to “our” solar systems future.
Says Farihi, “The beauty of this technique is that whatever the Universe is doing, we’ll be able to measure it. We have been using the Solar System as a kind of map, but we don’t know what the rest of the Universe does. Hopefully with Hubble and its powerful ultraviolet-light spectrograph COS, and with the upcoming ground-based 30- and 40-metre telescopes, we’ll be able to tell more of the story.” He went on to offer “We have identified chemical evidence for the building blocks of rocky planets,” says Farihi. “When these stars were born, they built planets, and there’s a good chance that they currently retain some of them. The signs of rocky debris we are seeing are evidence of this — it is at least as rocky as the most primitive terrestrial bodies in our Solar System.”
Going forward the evidence of these asteroids will point to the systems likely to contain Earth-sized planets. Planet-forming processes often form more small planets than the larger ones, but once debris yielding the rocky embryos are located, the Earth-sized planets are sure to be found.