Astronomy news

The Sun and the Asteroid

At www.physorg.com/print251533118.html ... a piece on sunspots and solar flares and an image of a solar flare from March 13th. The flare is described as a burst of radiation yet goes on to say the radiation is derived from the release of magnetic energy.

NASA mission to the Sun

At www.physorg.com/print251143024.html ... namely, the Solar Probe Plus mission and a piece of electronic wizardry being assembled by Justin Kasper - eyes across 100 million miles of space. Within 7 years the planned mission will journey to the centre of the solar system in order to study the solar wind. It will address key points - how does the corona heat to a phenomenal degree and what powers the solar wind, the stream of charged particles that flows from the corona.

Near Miss to Miss us again

At www.physorg.com/print251104689.html .... we learn that the asteroid that came close to earth earlier in the year will do the same thing next year. Known as 2012 DA14 it has an orbit synchronised with that of the earth's orbit - and it jumps inside and outside of the path of the earth two times a year.

WISE mapping

At www.sciencedaily.com/releases/2012/03/120313163921.htm ... 'flying through a geomagnetic storm' is an astronaut onboard the International Space Station commenting on what he can see as he flies over the auroral light show.

Dione

The Cassini spacecraft has detected a thin atmosphere that includes oxygen and ozone on Saturn's moon, Dione - see www.jpl.nasa.gov/news/news.cfm?release=2012-056&cid=release_2012-056. Admittedly, it is a faint atmosphere but enough to get news of it published in Geophysical Research Letters. Oxygen, it seems, is common in the Saturn system, already detected on the moon Rhea and in the rings around the planet.

Fireballs in February

At http://fireballs.ndc.nasa.gov there is information on fireballs over North America - and presumably elsewhere too. The story can also be seen at www.physorg.com/print249203167.html and it seems that in this february just gone there were some rather large space rocks entering the atmosphere of the earth. They were peculiar in that they were slow and penetrated much further and deeper than they are prone to do, breaking up closer to the surface. The origin of them is also somewhat puzzling as they have different orbits and trajectories.

Titan

At www.jpl.nasa.gov/news/news.cfm?release=2012-048&cid=release_2012-048 there is some interesting information available about Saturn's moon, Titan, the subject of a number of papers in the science press recently. The Cassini spacecraft has beamed back some wonderful images and has shown how Titan's atmosphere resembles that of the earth - with clouds, rainfall, and river valleys, lakes and other geological characteristics that have surprised astronomers to a certain degree.

The Earth ... spinning faster?

At www.physorg.com/print248347427.html ... tells us that a NASA JPL research team in league with French scientists have written a paper for the Geophysical Review Letters that claim that for a couple of weeks in 2009 the Earth was spinning faster, and days were shorter - by a fraction of time. This was all because the ocean current that encircles the Antarctic changed rate in response to a down step in wind speed. The change in speed of rotation was a self correcting motion in order to conserve angular momentum.

Venus ... variable day lengths

An unusual story can be found at www.esa.int/export/esaSC/SEM0TLSXXXG_index_0.html (hat tipped towards member Gary Gilligan) from the European Space Agency web site, 10th February 2012. ESAs Venus Express spacecraft has discovered Venus is rotating a little slower than when it was previously measured in the 1990s by NASAs Magellan Orbiter spacecraft. The measurements are said to be precise and detailed and the idea appears to be to find out if Venus has a liquid or a solid core. What might cause it to slow? It has a dense atmosphere which could influence the rotation rate, it is argued.

Black Holes gobbling Asteroids and Comets

This story is at www.sciencedaily.com/releases/2012/02/120208133039.htm and apparently the giant black hole at the centre of our galaxy may be devouring asteroids and comets, or anything that comes within munching reach. This, it is argued, will explain the frequent flares observed by NASAs Chandra x-ray observatory. The paper, published in Monthly Notices of the Royal Astronomical Society, suggests that large numbers of asteroids are needed in order to produce the amount of flaring in the assumed black hole. Why else would the flaring take place?