"NASA Probe Sees Solar Wind Decline. The 33-year odyssey of NASA's Voyager 1 spacecraft has reached a distant point at the edge of our solar system where there is no outward motion of solar wind."
Friday, December 31, 2010
7 Exoplanets (Amazing video)
"Hundreds of planets around other stars have been discovered recently, but many centuries may pass before human eyes actually see them up close. Interpreting current data, Hugo award-winning artist Ron Miller takes us to seven of the most fascinating of these worlds."
Wonderful!
"And while we are not quite ready for something like Star Trek’s United Federation of Planets, the almost daily discovery of new planets has brought the number of known worlds to well over 450."
"And while we are not quite ready for something like Star Trek’s United Federation of Planets, the almost daily discovery of new planets has brought the number of known worlds to well over 450."
T-Rex bad reputation got worse
It seems that the largest land predators, which ever stalked the earth, were cannibals. As reported among news in Telegraph UK (15 Oct 2010), the reserchers noticed bite marks on the bones of the dinosaurs. Comparing the marks, the scientists realised that a T-Rex was the only animal large enough to have caused them.
T-Rex, Museo Scienze
Thera and the biblical plagues
Thera, a volcano in the Mediterranean sea, produced with its explosion around 3,500 year ago, one of the biggest cataclysms in the human history. The remains of Thera are the Mediterranean islands of Santorini, north of Crete. As we can read from an article of Telegraph, the volcanic ash of eruption could have clashed with thunderstorms above Egypt, producing severe hail storms (one of the biblical plagues).
According to Prof.Trevisanato, a Canadian biologist, another plague, the locusts, could be explained by the volcanic fall out from the ash. The ash fall out caused weather anomalies, which produced higher precipitations and humidity, fostering the presence of the locusts. The volcanic ash could also have caused the plague of darkness. In fact, pumice stones have been found during excavations of Egyptian ruins despite there not being any volcanoes in Egypt.
Very interesting article.
According to Prof.Trevisanato, a Canadian biologist, another plague, the locusts, could be explained by the volcanic fall out from the ash. The ash fall out caused weather anomalies, which produced higher precipitations and humidity, fostering the presence of the locusts. The volcanic ash could also have caused the plague of darkness. In fact, pumice stones have been found during excavations of Egyptian ruins despite there not being any volcanoes in Egypt.
Very interesting article.
Thursday, December 30, 2010
Powering the space missions
Deep-space missions are powered by a RTG system. A radioisotope thermoelectric generator (RTG, RITEG) is a generator that obtains its power from radioactive decay. The heat released by the decay of a radioactive material is converted into electricity by the Seebeck effect using an array of thermocouples (see "how did Georg do it?").
RTGs are systems quite suitable as power sources for satellites and space probes and also for remote facilities where the use of solar cells is not feasible (for instance, lighthouses built by the former Soviet Union inside the Arctic Circle). RTGs are able to give few hundred watts for very long periods. The problem is to guarentee a safe use of radioisotopes.
RTGs are systems quite suitable as power sources for satellites and space probes and also for remote facilities where the use of solar cells is not feasible (for instance, lighthouses built by the former Soviet Union inside the Arctic Circle). RTGs are able to give few hundred watts for very long periods. The problem is to guarentee a safe use of radioisotopes.
Where is Cassini spacecraft?
Cassini–Huygens is a robotic spacecraft currently studying the planet Saturn and its satellites. The launched spacecraft consisted of two elements: the Cassini orbiter, named for the astronomer Giovanni Domenico Cassini, and the Huygens probe, named for the astronomer, mathematician and physicist Christiaan Huygens. Cassini-Huygens was launched on October 15, 1997, and it entered into orbit around Saturn on July 1, 2004. On December 25, 2004, the Huygens probe was separated from the orbiter and reached Saturn's moon Titan on January 14, 2005. It descended into the atmosphere of the moon, sending information back to the Earth. This was the first landing ever accomplished in the outer solar system. The mission will continue until 2017.
On November 2, Cassini was triggered into a standby mode, after a bit flip caused it to miss an important instruction. Cassini was reactivated as scheduled on November 24 and has returned to perfect working order, in time for two scheduled close fly-bys with Enceladus.
http://saturn.jpl.nasa.gov/index.cfm
http://saturn.jpl.nasa.gov/index.cfm
What is powering Cassini?
Bacteria in Titanic rusticles
TITANIC BEING EATEN BY DESTRUCTIVE BACTERIA, by Rossella Lorenzi.
"A new bacterium isolated from the Titanic wreck is accelerating the wreck's disintegration into a pile of dust."
These are bacteria potentially dangerous to underwater metal structures. Shipwrecks disapper but also offshore oil and gas pipelines. The articecle tells that the newly discovered species could also have positive applications for industry for instance in the recycling of iron structures in deep ocean.
"A new bacterium isolated from the Titanic wreck is accelerating the wreck's disintegration into a pile of dust."
These are bacteria potentially dangerous to underwater metal structures. Shipwrecks disapper but also offshore oil and gas pipelines. The articecle tells that the newly discovered species could also have positive applications for industry for instance in the recycling of iron structures in deep ocean.
Striges (Owls)
Strix (pl. striges or strixes) was the Ancient Roman and Greek word for owl. The name is Greek in origin. From it, the name of the genus Strix was derived.
