Astronomers Announce 5-Planet System 145
An anonymous reader writes "Astronomers have detected a record-breaking 5th planet orbiting the star 55 Cancri, 41 light years distant. This planet orbits within the 'habitable zone,' where water could presumably exist, but it's probably another gas giant like Saturn, so any liquid water would have to be on a moon. There's still a big gap between this planet and the outermost planet where no planets have been detected yet, so there could yet be a rocky planet in the system. The lead researcher said he's optimistic that 'continued observations will reveal a rocky planet within five years.'"
Re:How far has our reach extended? (Score:2, Informative)
Re:more planets to come! (Score:4, Informative)
Re:What Record? (Score:2, Informative)
Re:How far has our reach extended? (Score:2, Informative)
Television and radio signals are both part of the EM spectrum, all of which travel at C with varying levels of refraction depending on the medium it passes through.
That gives us a range of 71 light years for a civilization to have received the signal at all, and 35.5 light years if we would expect to hear a response from a civilization tomorrow.
Re:How far has our reach extended? (Score:5, Informative)
When did we first build powerful transmitters? Comercial radio started in the 1920's so almost 90 years ago. Higher frequency VHF got beg after the war in the lat 40's when TV got popular.
Could they hear it? Only if they have invested in VERY sensitive receivers MUCH more sensitive then anything we have. Our current receivers could only hear a signal if it were from a very powerful beacon aimed right at us.
We do not currently have a system then could detect our own signals if they were coming from another star.