NASA and JPL have announced the discovery of an Earth-sized planet orbiting in the habitable zone of its star. This has led to some popular press announcements that Earth’s twin has been discovered, but these planets are twins more in line with Danny DeVito and Arnold Schwarzenegger than identical twins. It should also be emphasized that being in the “Goldilocks Zone” of a star does not mean the planet harbors life, or even liquid water. So what do we know about this planet so far? Read more…
One Universe at a Time
Minnesota’s Soudan Underground Mine State Park is a former iron mine. Because of the orientation of the hematite, the mine had to go deep, and by the time of its close as an active mine in 1962 they were mining more than 2000 feet below ground level. Given its depth, and the geology of the region, the lower levels of the mine are well shielded from cosmic rays, which makes it a perfect location for sensitive experiments such as the search for dark matter. This is why it’s the location for the Cryogenic Dark Matter Search (CDMS).
There is a hexagonal cloud pattern at the north pole of Saturn. It was first discovered by Voyager in 1981, and was still there when Cassini arrived at Saturn in 2006. So it seems the pattern has been stable for more than 30 years. There’s been a great deal of debate about just how such a stable geometric shape could form in Saturn’s clouds, but it turns out the solution is surprisingly simple, and it traces back to some early experiments of Newton.
Carbon 14 is radioactive, and decays over time. It is one of the ways we can date the age of living things long after they’ve died. The reason is because carbon 14 is generated in the atmosphere when high energy particles strike nitrogen atoms in the upper atmosphere, and living thing utilize that carbon while they are alive. Once they die the carbon 14 in them isn’t replenished, so as the carbon 14 decays it over time it gives us a measure of how long an organism has been dead.
Last month research project known as BICEP2 announced evidence of inflation within the cosmic microwave background (CMB). Now a new paper argues that a different effect known as a radio loop could produce similar results, which raises the question of whether inflation was detected after all.