Monthly Archives: May 2010

Things to read, things to do

The magazine Popular Science is a 138 year old publication, offering scientific insights into everyday things as well as a potential glimpse of the everyday from tomorrow. But what about the tomorrow of yesterday? How did things look then? Well, now you can find out for free as the entire archive of Popular Science has been put online in collaboration with google. Past editions are shown complete even down to their contemporary adverts. Just as some other publications choose to wrap up even today’s articles in paywalls…

But what about more indepth actual science? What is going on in astronomy? A review paper of the past decade in astronomy and astrophysics has looked up the one hundred most cited (ie given as evidence or interest in newer papers) papers published in the years 2000-2009. Analysis shows that the papers are more heavily biased to collaborations than ones with fewer authors (self-citations were not removed or accounted for in this study). Extragalactic topics put papers in that stay for the shortest time in the top 100 and the top papers tend to be much longer than average. Databases being repeatedly mined mean that people who produce them and make them available will find high returns in terms of papers produced using them. The paper finds there are between 34-43 astronomy or astrophysics journals (Nature and Science are multidisciplinary, therefore not exclusively astro related) of which the top five account for the lion’s share of all papers in the top 100 (80-85%) as well as in the top 1000 (77%) – although they do produce around 80% of all articles covered in this survey. These are Monthly Notices of the Royal Astronomical Society, the Astrophysical Journal, the Astrophysical Journal Supplement Series, the Astronomical Journal and Astronomy & Astrophysics. All are European imprints with three IoP and one RAS related journal (Nature is also London based with Science the sole US publication). The numbers of citations are well correlated to citation rank by a power law. 9 papers are cited higher than the level suggested by the law, of which seven are related to WMAP releases, one covers a one off cosmic ray observation and the other a stellar evolution model. The number of publishes papers is increasing at a rate of around 3% a year. The survey was compiled by Jay A Frogel of the New York based Association of Universities for Research in Astronomy.

And what about the future itself for a specific area of science. The Global Lunar Conference 2010 aims to bring together scientists to show off results, network and bring together working groups to tackle the issues in lunar research. It began today in China and will run until Thursday. There are no bank holidays in scientific investigation.

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A couple of particle related bits

Neutrinos cause a lot of problems. These ‘ghostly’ particles have a habit of only interacting very weakly with ordinary matter, making their detection rather difficult. They are produced in massive numbers by fusion reactions inside the Sun, potentially giving us detailed information on what’s going on, but when we measure the type (or ‘flavour’) of neutrinos coming from the Sun, the ratios of each flavour don’t add up to what we’d expect (although the overall numbers are fine now we can add up the numbers of each flavour). A lot of head scratching later and the idea of neutrino oscillations came about. This focuses on wave-particle duality which essentially means every particle in the universe has some level of wave-like actions and some particle like characteristics. So photons of light hitting metals don’t impart their energy continuously like waves breaking on the shore, they give one pulse of energy, then another (meaning electrons requiring a certain amount of energy to leave the metal won’t do so until photons over a certain energy come at them). It also means particles like electrons can undergo wave like interactions like diffraction and interference. It was also suggested that neutrinos – particles – could interfere with one another in a wavelike way such that a group of different flavours would appear to contain a different ratio of flavours to the actual amount that were present when the beam came together. This is neutrino oscillation.

The oscillations required something that hadn’t at the time been measured – the neutrinos needed to have mass. An experiment was soon performed that didn’t show the masses of the neutrinos, but instead showed that the flavours – electron, tau and muon (plus their anti particles, named after the particles whose creation spawned them) – all had differences in their mass. If there were differences, then at least some of them had to have mass, which was enough to allow oscillations to occur. But some doubts still persisted as the oscillations themselves had never been seen – until now.

At the OPERA facility in Italy, they measure the numbers of muon neutrinos spawned by decays in the LHC in CERN, 730km away. They have an idea how many are being produced and where they’re headed over there and how many should be arriving where they are. They also know how many in theory are going to change from being muons to tau neutrinos. Now they have announced that a tau has been produced in a pure muon stream, the first tentative step to showing that oscillation happens – though a few more detections would be nice just to show there’s a trend here.

Meanwhile, in other astroparticle news, the IceCube detector has been looking not at muon neutrinos, but at muons themselves. Muons are a class of particle called Leptons that includes electrons and tauon particles, their anti-particles and their neutrinos. They are the heaviest of the leptons and so the least likely to pop into existence. They are created in high energy interactions and can be accelerated to high energies. The creation and acceleration of such exotic particles by magnetic fields and shockwaves associated with supernovae and stellar remnants such as neutron stars. But there’s been little evidence that this is so. There are limits to the energies of cosmic rays (hugh energy particles born outside of Earth) coming in from outside the solar system. On the low energy scale, the magnetic fields of the Earth and the solar wind deflect those charged particles that aren’t travelling our way with enough momentum. At the highest energies, charged particles are slowed by brehmstrallung radiation that opposes acceleration. Travelling through the cosmos, particles from various sources encounter the magnetic fields of interstellar space and are slowly massaged into a fairly constant background. But some relatively close structures can still be seen lurking in images of the sky taken using particles rather than light.

The map of incoming muons produced by IceCube, which is a nascent neutrino observatory, has shown there to be a slight excess of cosmic rays from the direction of the Vela supernova remnant. This remnant is 800 light years from us and 10,000 years old. Between it and us there is a second supernova remnant, often missed as it shines less brightly across most wavelength ranges (but still more brightly in gamma rays). Vela was the place where an observed neutron star was linked to a supernova remnant directly for the first time, could it now be the place that the first tentative observational proof of cosmic ray acceleration in such a system has been achieved?

…and sticking with muons for a moment. Fermilab recently released data on muon production at its particle accelerator facility. The data showed that production of muons outstripped production of anti-muons in proton-anti-proton collisions by about 1%. This is an important discovery, if confirmed, which could show the reason why the local universe is dominated by matter, rather than having equal amounts of matter and anti-matter. It has been hypothesised that this imbalance exists between the amount of matter and anti-matter generated in particle interactions, with subsequent annihilation between the particles leaving the excess of matter behind to form the things we see.

WMAP leaders honoured

The Shaw Prize, an equivalent to the Nobel Prizes, is awarded to living “individuals, regardless of race, nationality and religious belief, who have achieved significant breakthrough in academic and scientific research or application, and whose work has resulted in a positive and profound impact on mankind.” in the fields of Astronomy, life science & medicine and Mathematics. The prize is a medal and $1 million. Instituted in 2004, 22 prizes have been awarded to 36 individuals, with the astronomy prize dominated by cosmology and extrasolar planets (consistent with the emphasis of recent years).

This year’s prize for astronomy was split between three individuals, Charles L Bennett, Lyman A Page Jr and David N Spergel leaders of the Wilkinson Microwave Anisotropy Probe, or WMAP satellite, which measured fluctuations in the Cosmic Microwave Background, or CMB.

A quick rundown of other prizes awarded to CMB scientists has been put up at SarahAskew.net.

Where to go, what to see

The Daily Telegraph has put together a list of the best places to see the stars in Britain (and a few places to stay when visiting these areas). They based their positions on Dark Skies maps such as this one, this one and this one.

But what might you see? A show of the young and the old in terms of targets available to stargazers has been put on in this photograph showing the International Space Station in some detail as well as the planet Jupiter. Sadly, the clicks didn’t get the two side by side or even overlapping as was possible, but both targets were in the same vicinity at least. A challenge for the rest of us there… It should be noted that the image was taken with a 16cm telescope in daylight – so no excuses!

The lungs of Europa

Europa is one of Jupiter’s ‘big’ Galilean moons and the one that has received the most scrutiny when it comes down to finding life in another part of the solar system. The moon is covered with a layer of ice around five kilometres thick and beneath this an ocean up to 160km deep. The ocean survives in the bleak, frozen wastes of that part of the solar system due to gravitational interactions between Jupiter and Europa over the course of its orbit, warming it a little inside.

Heat and water, check, possible hydrocarbons from cometary debris check. But for Earth like organisms to flourish, a little something else is required – oxygen. We know that ice molecules on the surface of Europa are broken into oxygen and hydrogen atoms and molecules through both particle and photonic radiation from the giant planet. We also know impacts can push the material down, but only down to a certain depth well short of the subsurface ocean – Europa’s air is trapped in its throat unable to get to its lungs. However, a study of resurfacing on the moon suggests the oxygen can get a little deeper.

Europa is criss-crossed with ridges, rather like those on the seafloor on Earth, and like the seabed ridges here, they are places where material is upwelling from the warm interior of the body to form a new surface. In the case of the Earth, new seafloor comes from magma rising to fill the ridge and push it apart. On Europa, water is rising and forming new ice. Where there is formation, there must be destruction in order for Europa to have maintained such a thin outer crust. Somewhere, subduction must be happening, where old ice is forced underneath another layer of old ice and into the ocean, where it melts – similar to the edges of tectonic plates on Earth. As the old ice is mixed into the water below, it takes with it the oxygen on the surface.

In addition, erosion of the bottom of these ‘plates’ during the warmer periods of the orbit (when gravitational stresses are high, generating internal heat) and refreezing of the same blocks of ice could also lead to migration of oxygen rich material into the ocean. Calculations performed based on what we know of the icy tectonics of Europa suggest that sufficient oxygen to support the equivalent of millions of fish could be finding its way into the alien world. No proof that they are, and indeed one would suspect with upwelling of material, there would be an indication on the surface close to the ridge, but maybe that’s a game changing observation still to be made.

Places to go, people to see

Musician, historian and astronomer Dr Allan Chapman, will be giving a talk on the 11th of June to the Mexborough and Swinton Astronomical Society at the Meeting Room at the Swinton Working Men’s Club. His talks are sought after and very interesting, so don’t miss it if you’re in the area on the day.

Meanwhile, if you’re off on a toddle during this extended weekend and want something to look at this website details known impact structures across the world. None in the UK listed so far, but plenty in other places around the world.

Cuts and investment

Prepare for a news sandwich…

Good News!

The US House of Representatives has, on the third asking, approved funding for research development under the COMPETES Act. The Act essentially encapsulates the case for increased science funding as a way to grow the economy. The full name is the America Creating Opportunities to Meaningfully Promote Excellence in Technology, Education, and Science Act and it was first signed into being in 2007. This round was a renewal of the funding in the original act, which goes toward increased research funding, visas for skilled workers, a trained teacher corps and R&D tax credits.

Not so Good News!

The President of the Royal Society has suggested that the cuts and present level of science funding are making the UK uncompetitive in the scientific skills labour market. In the Times report, John Womersley, director of science programmes at the Science and Technology Facilities Council (STFC), the research council in charge of UK Physics and Astronomy tried to portray his council as a model of austerity (due to the cuts imposed over the past four years due to financial mismanagement and incompetent actions at various levels of government). Unsurprisingly, Jim Al-Khalili, a professor of Physics at the University of Surrey, also holds the STFC up as a model – of the worst that can happen when funding goes bad. The Times also carried a couple of profiles of people forced out of science due to the actions of the STFC. It is not hard to find names for such reports.

Good News!

But at least someone’s headed for the Moon. A Japanese Government panel are putting together the final touches of a rough plan for a base on the Moon. The base will have solar panels and protection against the worst the solar wind can throw at it, but it will not (initially at least) be designed for human occupation – it is a Moon base for Robots.

Rumours David Willetts has tasked the same panel to create a new STFC are entirely unfounded.