Astronomy news

Venus ... in the eye of a Japanese spacecraft

There are two stories on Venus today and both are well worth keeping an eye out for updates.

NGC 4696

At www.sciencedaily.com/releases/2010/08/100812065911.htm we have, 'NGC 4696: A Cosmic Question Mark'. It's all about a strange galaxy that curls around at one end like a great question mark in outer space, on the edge of the field of vision of the Hubble Advanced Camera. It is the biggest galaxy in the Centaurian cluster and is at the moment a bit of a mystery.

Giant loops of ultraviolet light in deep space

At www.jpl.nasa.gov/news August 11th ... astronomers have found giant loops of ultraviolet light in old galaxies which seem to have a second lease of life. The discovery implies that such galaxies, that appear to be dead, or are assumed to be dead by astronomers, are not so.

A Solar Tsunami (?)

At www.dailymail.co.uk/sciencetech/article_1302449/Spectacular-northern-lights-dance-over-lakes-in-wake-of-solar-tsunami/ ... it seems the journalist is describing a solar flare, and presumably his analogy with a tsunami wave comes from the rapid advance of plasma from the Sun towards the earth as a result of the flare.

The Spacecraft Fly-by Mystery

'The Spacecraft fly-by mystery - is dark matter the culprit or is there new physics waiting to be discovered?' is another headline grabber from Casey Kazan at www.dailygalaxy.com on August 3rd. When NASA sends its spacecraft across the solar system they save fuel by making use of sling-shot fly-bys. Rather than firing up thrusters the spacecraft changes trajectory by harnessing the gravitational pulls of the planets. However, this clever trick has had an unexpected side-effect.

The Sun is waking up

The Sun is waking up according to NASA - see www.physorg.com/print199985777.html which  has an image of a filament of plasma blasted from the surface (plus access to a video clip)

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.