Based on new calculations, an astronomer has proposed the existence of an unseen planet four times the size of Earth lurking in the outer reaches of the solar system.
A planet turning to dust.
More information on the annular solar eclipse coming to the southwest U.S. this Sunday.
Actually, the second link above provides better information on where and when to view the eclipse. Definitely click on the map showing the national parks where viewing will be best.
Set your calendar: The first solar eclipse to cross the continental United States in two decades will occur on May 20.
An annular solar eclipse occurs when the moon passes between the earth and sun, but the lunar disk does not completely block out the sun and instead leaves a “ring of fire” visible around the moon at the point of maximum eclipse. Most anyone west of the Mississippi will see a partial eclipse, but the real treat will be for those located in the 200-mile wide path of the eclipse which will trek east from the California / Oregon border through Nevada, Utah, Arizona, New Mexico, and finally set below the horizon in west Texas.
Remember, you will need good eye protection if you choose to look.
A Japanese astronomy professor has been found murdered in Chile.
One astronomer has found that the inner edge of the habitable zone around some dwarf stars is smaller than first calculated because tidal forces overheat planets close to the star.
Then again, this heating might expand the habitable zone in other directions. Stars might overheat when close to the star, but get a boost of needed heat when they would normally be too far away.
The uncertainty of science: Astronomers now believe that Type 1a supernovae — used to discover dark energy — can be produced in two different ways.
Type Ia supernovae are known to originate from white dwarfs – the dense cores of dead stars. White dwarfs are also called degenerate stars because they’re supported by quantum degeneracy pressure. In the single-degenerate model for a supernova, a white dwarf gathers material from a companion star until it reaches a tipping point where a runaway nuclear reaction begins and the star explodes. In the double-degenerate model, two white dwarfs merge and explode. Single-degenerate systems should have gas from the companion star around the supernova, while the double-degenerate systems will lack that gas.
For astronomers, this possibility raises several conflicting questions. If two different causes produce Type 1a supernovae, could their measurement of dark energy be suspect? And if not, why is it that these two different causes produce supernovae explosions that look so much alike?
Using the Moon as a mirror.
The uncertainty of science: Scientists have discovered that the half life of one of their key isotopes for dating the age of the solar system is 30% shorter than previously believed.
The main result of the work of the international scientists, detailed in a recent article in Science, is a new determination of the half-life of 146Sm, previously adopted as 103 million years, to a much shorter value of 68 million years. The shorter half-life value, like a clock ticking faster, has the effect of shrinking the assessed chronology of events in the early solar system and in planetary differentiation into a shorter time span.
The new time scale, interestingly, is now consistent with a recent and precise dating made on a lunar rock and is in better agreement with the dating obtained with other chronometers. The measurement of the half-life of 146Sm, performed over several years by the collaborators, involved the use of the ATLAS particle accelerator at Argonne National Laboratory in Illinois.
Ground-based astronomy moves forward: The Department of Energy has approved the start of detailed engineering for the camera on the Large Synoptic Survey Telescope.
I have to admit, I am puzzled why the Department of Energy is involved in this. Government funding for ground-based telescopes normally comes from the National Science Foundation.
Europe has decided to build a probe to study Ganymede, Callisto and Europa, Jupiter’s big icy moons.
Known as JUICE, the Jupiter Icy Moons Explorer, the probe will enter orbit around the gas giant planet in 2030 for a series of flybys of Ganymede, Callisto and Europa. JUICE will brake into orbit around Ganymede, Jupiter’s largest moon, in 2032 for at least one year of close-up research.
