Astronomy news

Speaking of Water

Speaking of water, scientists discover evidence of recent water flow on Mars - see https://phys.org/print430640889.html ... and the scientists in question come from a number of universities and countries but the lead author is from the Open University in Milton Keynes. They claim they have found evidence of recent glacial meltwater in spite of the widely held opinion that the climate on Mars is too cold to melt ice. The evidence in question revolves around the identify of an esker (what they interpret as an esker and it does look very much like it is).

Space Dust

Space dust can transport life between planets - see www.astronomy.com/news/2017/11/life-in-dust#.Whh0luAwbyE.mailto ... dust and debris form ancient asteroid collisions, and outflow from comets as well as interstellar dust is pervasive throughout the solar system. Space is not empty. It is full of dust and no doubt, bigger grains, from gravel to rocks. Roughly 220,000lbs (in old money) of space dust falls on to Earth each day, we are told. In deep space streams of cosmic dust can travel at speeds up to 44 miles per second.

Quirky Comet

At https://phys.org/print430554336.html ... when a comet passed through the inner solar system at the beginning of 2017 it presented astronomers with the chance to turn their telescopes in its direction - and analysis is said to have filled in some crucial details what ices in Jupiter family comets do. Ices in this instance mean frozen gases. The comet it seems did not meet expectations as it is described as quirky - or different from other comets. The team measured 9 gases released from the nucleus into the coma.

Moon Origins

Sent in by Gary. At www.dailymail.co.uk/sciencetech/article-5105879/The-moon-s-surface-solid... .... the Moon's surface was a magma ocean - until it solidified. How long did that take? We are told that long before the Moon came to be covered in a solid and cratered crust (the situation nowadays) it was a massive ocean of molten magma. One theory is that this accounts for the crust's so called purity - it is primarily made up of a single mineral. A new study suggests a secondary event may be to blame.

Empty Space

The way physicists represent the universe and its history are described in Einstein's equation of general relativity, Newton's universal gravitation, and quantum mechanics. The consensus at present supports Big Bang followed by expansion. According to Andre Maeder dark matter and dark energy are only required to make it all fit together because they ignore empty space. He argues empty space and its properties do not change following a dilation or a contraction.

Sand not water

At www.jpl.nasa.gov/news/news.php ... and https://phys.org/print430401551.html ... Martian streaks, dark lines on Mars thought to be evidence of sub-surface flowing water are now thought to be where grains of sand and dust slip downhill to make streaks rather than seeping water. The Mars Renaissance Rover camera has been studying them and found they only occur on steep slopes ...

   ... they behave like sand grains tumbling on sand dunes on Earth.

Oumuamua

At http://spaceweather.com (November 20th) we have news of another round of solar wind making a rendevous with the Earth in the next few days, coinciding with a mild November here in the UK. We also have an image of an 'interstellar asteroid' first seen by the Pan-STARRS telescope weeks ago when it was thought to be an interstellar comet. It is now classified as an asteroid as it has failed to bring on a cometary show as it approached the Sun. It is passing through the solar system ...

Ceres

The DAWN mission is still throwing up info - see https://phys.org/print429466672.html ... a study in Geophysical Research Letters analysed surface features on Ceres in order to find clues about the interior of the asteroid. Chains of pits and small craters and other features litter the surface. Upwelling from below is thought to have created them. See the image below ...

Neutron Star Collision

Worlds in Collision becomes ever more popular with astrophysicists and astronomers and is basic to the gravitational wave theory currently getting a lot of attention - colliding neutron stars and merging black holes. Apparently, a nearby neutron star collision could cause calamity on Earth - but think of all that gold and platinum it would produce. Even merging black holes would be a disaster, if they occurred too close to our galaxy - and that old bugbear, a supernova event would also be deadly. How near is near?

One Step Closer

Again, this is astrophysics rather than astronomy but never mind, its the universe. The claim is that scientists are one step closer to defining dark matter - go to https://phys.org/print428759704.html ... where  we are told the search is on for dark matter - where it is and what it might be. Dark matter, we are led to believe, makes up to 85 per cent of all matter in the universe. We are apparently another step closer to discovering how to detect dark matter and to define it more accurately. What kind of particles are involved?