Radial velocity observations measuring the gravitational tug exerted by KOI-254 b on KOI-254 gives KOI-254 b a mass of 0.505 times the mass of Jupiter. The estimated equilibrium temperature of KOI-254 b is 1000 degrees Kelvin. What makes KOI-254 b unique is that it is the first known Jupiter-mass planet in a short period orbit around a red dwarf star. Apart from KOI-254 b, there is no known planet above 0.2 times the mass of Jupiter orbiting a red dwarf star with an orbital period of less than 10 days. Given the fact that close-in Jupiter mass planets should be readily detected around red dwarf stars, the lack of such planets mean that KOI-254 b is likely to be the only known example of a hot Jupiter around a red dwarf star for some time.
Thursday, May 31, 2012
A recent paper by John Asher Johnson et al. (2012) titled “Characterizing the Cool KOIs. II. The M Dwarf KOI-254 and Its Hot Jupiter” describes the discovery of the first hot Jupiter around a red dwarf star. Red dwarf stars are the coolest and least massive type of stars, and they also make up the majority of stars. The star involved is called KOI-254 and a gas giant planet orbits it once every 2.455 days. This gas giant planet is designated KOI-254 b and it was originally discovered by the Kepler mission from its periodic transits in front of KOI-254. During each transit, KOI-254 dims by 3.909 percent and from this, the size of KOI-254 b is estimated to be 0.96 times the diameter of Jupiter.
Tuesday, May 29, 2012
Anthropogenic low pressure regions occur when heat generated from human activities is injected into the atmosphere. Good examples include large coastal cities and large fires near coastal areas. For instance, the Kuwait oil fires during the Gulf War injected sufficient heat into the atmosphere to sustain heavy rainfall over the area. This occurs when the low pressure region created by the heat draws moist air from the Arab sea and the aerosols emitted by the fires serves as condensation nuclei for the moist air.
Deserts cover one third of the Earth’s land surface and they are characterised by extremely low amounts of precipitation. Strong solar heating during the day forms a natural low pressure region over a desert while at night; this is replaced by a high pressure region as heat absorbed during the day is rapidly lost. This creates a tendency for moist air over a neighbouring ocean to be drawn towards the desert during the day with the reverse occurring at night. Such a daily oscillation of airflow is unable to push moist air into the desert interior.
The injection of heat from nuclear reactors situated in the middle of a desert can maintain a persistent low pressure region and the constant suction can draw moist air from the ocean deep into the desert’s interior. This is expected to lead to an increase in the amount of precipitation and can potentially transform the desert landscape, allowing an increase in vegetation cover and creating more land for agriculture and human habitation. A cluster of nuclear reactors with a net heat output of 10 billion watts can create an effective suction radius of a couple of thousand kilometres around it. For example, if it were situated in the interior of the Sahara, it can draw in moist air from the Atlantic Ocean and Mediterranean Sea, transforming the Sahara into a lush and fertile region.
During the day, the surplus heat energy produced from the nuclear reactors can be converted into electricity or can be used to convert atmospheric carbon dioxide into commercial-grade gasoline, diesel fuel and jet fuel. The use of such hydrocarbon-based fuels is carbon neutral since the net amount of carbon dioxide released back into the atmosphere is zero.
1. Moninder Singh Modgil (2002), “Large Scale Weather Control Using Nuclear Reactors”, arXiv:physics/0210008v1 [physics.ao-ph]
2. Moninder Singh Modgil (2008), “Climate Control Using Nuclear Energy”, arXiv:0801.0320v1 [physics.gen-ph]