Astronomy news

Icy Centaurs

Are icy centaurs between the orbits of Jupiter and Neptune a threat to the earth? is the headline of a piece by Casey Kazan at www.dailygalaxy.com August 2nd ... He says the greatest threat to earth comes from comets and NASA has found it difficult to keep a track on these objects. Most comets are on orbits that enter the inner solar system at intervals of two to three hundred years.

Lots of dark matter in a recently discovered galaxy

www.sciencenews.org/view/generic/id/61683/title/Dark-matter-eldorado/ a report online at arXiv.org that claims that a galaxy discovered in 2007, known as Segue's Galaxy, is composed almost entirely of dark matter (because very little can be seen). Is that logical? 

Dunes on Titan

NASAs newsletter, at www.jpl.nasa.gov/news/ July 29th says the mystery of dune patterns on Titan might have been solved. Dune patterns flow in the opposite direction to the wind. Huge dunes sweep across vst sand seas at mid latitudes on Titan and the ridges generally run from E to W, in the opposite direction. It is thought the wind must in some way switch direction on occasions.

A 25 Year Theory bears fruition

At www.physorg.com/print199363299.html ... in 1984 space pioneer Dr Robert Forward proposed a way of improving satellite telecommunications using a new family of orbits. His critics claimed it was impossible but now, engineers at the University of Strathclyde have proved Forward was right according to a paper in Journal of Guidance, Control and Dynamics. Satellites normally follow orbits based on Keplers law of orbital motion but a new family of orbits do not follow the same rules.

Swarms of black holes and small rock earth like planets in the Milky Way galaxy

At www.dailygalaxy.com July 28th there are two interesting stories. The first concerns the claim the Milky Way is rich in small rocky earth like planets (with a video clip of the sky in support of the text). Hence, there are lots of earth like planets out there which might harbour life - which explains why Martin Rees, elsewhere, the Astronomer Royal and Royal Society bigwig, was confident that life would be found in the not too distant future.

Impact craters on the Moon

Go to http://cosmictusk.com/moon-to-earth-new-lro-lunar-crater-analysis-has-potential-to-revise-impact-frequency-for-terrafirma/ ... by comparing modern images of the surface of the moon with images collected by Apollo missions in the 1970s it has been found five new craters have appeared in the past 40 years.

Where did Time come from?

At www.dailygalaxy.com July 22nd we also have a piece with the title, 'Did we inherit Time from an earlier universe?' (which includes a video clip). A team of physicists studying the cosmic microwave background, light emitted when the universe was a mere 400,000 years of age, have claimed our view of the early universe may contain the signature of a time before the Big Bang. Their discovery may help explain why we experience Time moving in a straight line from yesterday into tomorrow.

X-Galaxies

'The X-Galaxy: A Cosmic Radio Mystery Solved' is a post on July 22nd at www.dailygalaxy.com in which radio images from the X Galaxy (how it is notated in article) show a bright pair of jets pointing from L to R and a fainter more distant line of radio emissions running in a different direction. There are in fact a class of X-shaped galaxies, so called because of the outline of their radio emissions and not by their actual shape.

A Dark Secret

www.physorg.com/print198949672.html ... is another story that might be a repeat, 'Does the Sun hold a dark secret?' - perhaps dark matter is at the centre of the Sun and cooling down its core. Yes, I'm sure this was a Daily Galaxy storyline - but here it comes from the mouth of the scientist concerned rather than a commentator.

Water on the Moon

www.eurekalert.org/pub_releases/2010-07/uota-urd072010.php this story, sent in by Garry Gilligan, is all about water on the moon - and how new research is turning what scientists thought they knew on its head. The moon was supposed to be bone dry but researchers found 'lunar dew' and not it has been discovered that water itself is more widespread - on the outside and on the inside of the moon. A comparison has been made with water in volcanic systems on earth.