Friday 1 May 2015

FOR MAY DAY



An excerpt from The Shepherd's Calendar, May.
John Clare Poet (1793 - 1864)

...
Come queen of months in company
Wi all thy merry minstrelsy
The restless cuckoo absent long
And twittering swallows chimney song
And hedge row crickets notes that run
From every bank that fronts the sun
And swathy bees about the grass
That stops wi every bloom they pass
And every minute every hour
Keep teazing weeds that wear a flower
And toil and childhoods humming joys
For there is music in the noise



John Clare – The Shepherd’s Calendar (May - excerpt)
(With thanks to Roger Arborfield)

Thursday 30 April 2015

25 YEARS OF THE HUBBLE SPACE TELESCOPE

The Hubble Space Telescope has completed 25 years of astronomical observation since its launch on 24 April 1990.
http://www.bbc.co.uk/news/science-environment-32433839

Nasa Administrator Charlie Bolden said 'A quarter of a century later, Hubble has fundamentally changed our understanding of our Universe and our place in it'.

An early problem was a flaw found in the telescope's primary mirror that blurred its images A smart fix was installed by spacewalking astronauts in 1993 that allowed its instruments to correct for the aberration in the reflecting surface.

Engineers expect the observatory to keep operating for at least another five years. Its successor , the much bigger James Webb Space Telescope, is due for launch in 2018.

The scientific contribution of Hubble is enormous. Before Hubble, astronomers did not know whether the Universe was 10 billion or 20 billion years old. Hubble's study of pulsating stars narrowed the uncertainty. The age of the Universe is now known to be 13.8 billion years. Hubble also played a part in revealing the expansion of the Universe, and provided definitive evidence for the existence of super-massive black holes at the centre of galaxies, among many other discoveries.

Comment: The images received from Hubble have been truly breathtaking, and often stunningly beautiful. Hubble in many ways has revolutionised astronomy and cosmology.

Tuesday 31 March 2015

DARK MATTER AND GALACTIC COLLISIONS

New observations on collisions of clusters of remote galaxies have shed further light on the nature of dark matter, enabling some theories to be ruled out.
http://www.bbc.co.uk/news/science-environment-32066013

Astrophysicists studied 72 collisions between galactic clusters. Visible light was recorded by the Hubble Space Telescope, and x-rays by the Chandra Observatory. The researchers tracked the movement of the three main components of galaxies: stars, clouds of gas, and dark matter.

Although dark matter, which makes up 85% of the matter in the universe, does not emit or absorb light, it does have gravity and its presence can be detected by its bending effect on light passing nearby.

Dr Richard Massey of Durham University and colleagues were able to map the dark matter during the galactic collisions. Unlike the gas clouds which interact strongly, and stars which glide past, the dark matter passes through everything and emerges unscathed.

The strongest result from the study was further evidence that dark matter really is present in the galactic clusters. Further, many theories of dark matter can now be ruled out, for example that dark matter is a  'dark version' of ordinary matter, made of 'dark atoms'.

Comment:  Dark matter and energy are slowly yielding their mysteries to these astrophysical observations. It's difficult not to feel that one day there will be a major breakthrough in our understanding.

Tuesday 24 February 2015

REMEMBERING FUKUSHIMA NUCLEAR DISASTER 

There are several events in London next month marking the fourth anniversary of the Fukushima nuclear disaster, and opposing nuclear power. August this year will see the seventieth anniversary of the nuclear destruction of Hiroshima and Nagasaki.   I'm speaking at SOAS University of London on Tuesday 3 March, and also at the rally in Parliament Square at 2.30 pm on Saturday 14 March.



LARGE HADRON COLLIDER SEARCH FOR GLUINO

The Large Hadron Collider (LHC) is due to restart next month after an energy-boosting upgrade, following the crucial discovery of the Higgs boson:

http://www.bbc.co.uk/news/science-environment-31476337

Doubling the LHC collision energy may take it into the domain of dark matter particles, as predicted by Supersymmetry, which is  a theoretical addition to the Standard Model of particle physics. Most of the matter in the Universe is believed to be in the form of dark matter. There may be many dark matter particles, partners to the ordinary matter particles. Initial candidates for discovery by the LHC are the gluino (the partner of the gluon which holds the quarks together inside protons and neutrons) and the neutralino.

Professor Beate Heinemann of the University of California at Berkley, a spokeswoman for the Atlas experiment at the LHC, says: 'We hope that we're just now at this threshold that we're finding another world, like antimatter for instance. We found antimatter in the beginning of the last century. Maybe we'll now find supersymmetric matter.'

Dr Michael Williams of Massachusetts Institute of Technology (MIT) said: 'Finding any particle that could be a dark matter candidate is nice because we could start to understand how it affects the galaxy and the evolution of the universe, but it also opens the door to whatever is on the other side, which we have no idea what is there.'

Comment: These are adventurous and exciting times for particle physics and cosmology. A feeling that we may be just on the verge of major new discoveries that could change our view of the universe.


Sunday 1 February 2015

COSMIC INFLATION MEASUREMENTS ERROR

A new study of cosmic inflation involving the BICEP2 team of scientists has concluded that results announced last year were in error due to light emission from dust in our own galaxy:

http://www.bbc.co.uk/news/science-environment-31058529

BICEP2 used extremely sensitive detectors in an Antarctic telescope to study light coming to Earth from the edge of the observable universe - the Cosmic Microwave Background Radiation (CMBR).

It was looking for swirls in the polarisation of the light, called B-modes, which are an imprint of the waves of gravitational energy that would have accompanied the early inflation of the universe fractions of a second after the Big Bang.

The scientists now believe that false B-mode signals in the measurements reported last year arising from dust in our own galaxy lead to a reduced significance in the results, and they are unable to confirm that the signal is an imprint of cosmic inflation.  

Other experiments are now attempting to resolve the B-mode signal using a variety of detector technologies and telescopes.

Comment: This is leading research and these developments are steps forward rather than setbacks.

Saturday 31 January 2015

GREECE SOLIDARITY CAMPAIGN'S SYRIZA RALLY

A rally celebrating the stunning victory of Syriza in the Greek general election was held on Wednesday 28 January at the TUC Congress House in London, attended by supporters of the Greece Solidarity Campaign and Syriza members from Athens. 



The new Syriza government has already taken urgent action to remove some of the worst injustices inflicted on the Greek people by Austerity policies.

SELLAFIELD NUCLEAR CLEAN-UP CONTRACT LOST

Private consortium Nuclear Management Partners (NMP) will be stripped of the £9bn contract to clean-up the nuclear waste site at Sellafield, the biggest and most complex nuclear site in Europe:

http://www.bbc.co.uk/news/business-30785623

NMP has run the site for more than six years. The private consortium has been heavily criticised; both the Public Accounts Committee and the National Audit Office have accused NMP of overruns and delays. NMP's contract was extended for a further five years in 2013.

The Nuclear Decommissioning Authority (NDA),  which awarded the contract, last year increased its estimate for cleaning up the UK's nuclear sites by 7% to £110bn over the next 120 years. The vast bulk of that relates to Sellafield.

Comment: This debacle illustrates the enormous costs, the timescale disappearing into the distant future, and the short-term profiteering of private consortia involved in the clean-up of the waste from nuclear power.

Thursday 22 January 2015

ROSETTA DATA HINTS AT COMET FORMATION

New pictures from the Rosetta probe of the surface of Comet 67P reveal a lumpy texture in places that researchers speculate could have been the comet's original building blocks.
http://bbc.co.uk/news/science-environment-30931445

Cameras on Rosetta have now imaged 70% of the comet's surface. The unseen fraction, in the southern hemisphere, will be mapped as it emerges from the darkness of winter. The research team has defined 19 regions on the comet, giving each the name of an ancient Egyptian deity.

A striking occurrence is a kind of 'fluidisation' effect that acts to smooth some surfaces. Scientists think this occurs when ices change their structure. The change in phase results in a release of gas that can pick up local dust and make it move briefly like a fluid. Something similar is seen on Earth when large volumes of hot ash tumble down the sides of volcanoes.

It is obvious now that this comet is not a large lump of ice with some dust mixed in. It has a much more complex construction. incorporating significantly more dust and may rocky components. This is very evident from all those craggy cliff features where stiff, consolidated materials seem to dominate.

Simon Green of the Open University said: 'We used to think of comets as 'dirty snowballs'; we now think 'icy dirt-ball' is a much better description.. That's the way 67P looks - a solid object with ice vaporising from somewhere below the surface.'

Comment: It's clear from these latest published research findings that Rosetta is making important and exciting contributions to cometary science.

Wednesday 21 January 2015

FALLOWFIELD  in Winter

The River Lea meanders through Fallowfield yesterday on a frosty, sunny January day. The most natural, unspoilt and hidden riverside site in Luton, now a County Wildlife Site. A clump of Reed Mace in Boggy Mead, one of the three ancient fields here.




Comment: Fallowfield is on the flood plain of the River Lea, hence this urban site is undeveloped and preserves three ancient fields:  River Close, Boggy Mead and Catch's Close, within just a mile or so of Luton town centre.

Sunday 4 January 2015

WINTER SUN

Luton in the winter sun, two days ago along Cats Brook in Limbury. The little brook rises in Luton about a half mile away, and flows nearby into the River Lea. Haunt of Kingfishers, Herons, Little Egrets, and Minnows.


Saturday 3 January 2015

JOHN CLARE:      A WINTER WISH

My wish nows to sit in a cottage made snug

By a fire burning roozy and bright
With a Friend to make shorter short days by a Jug
And some Books for amusement at night
And could I enjoy such a peaceable lot
I'd ne'er cast on Fortune a frown
Nor would I possesing my Friend, Books, and Cott
Exchange 'em away for a — Crown!
 
(with thanks to Roger Arborfield)
 
Comment:  John Clare (1793 - 1864)  Foremost rural poet of the English Language. 

Friday 2 January 2015

CURIOSITY FINDS METHANE AND ORGANIC COMPOUNDS ON MARS

Mars Curiosity rover has detected methane on Mars, and has also found organic compounds in rock samples., hints of past or present life on Mars:
http://www.bbc.co.uk/news/science-environment-30456664

The source of the methane cannot be identified. Curiosity scientist Professor Sushil Atreya of the University of Michigan said 'It's possible that clathrates are involved. These are molecular cages of water-ice in which the methane gas is trapped. From time to time, these could be destabilised, perhaps by some mechanical or thermal stress, and the methane gas would be released to find its way up through cracks or fissures in the rock to enter the atmosphere.'

The methane could have got into the clathrate stores from Martian bugs, but it could also have come from a natural process which produces methane when water interacts with certain types of rocks. One way to investigate whether the Martian methane has a biological or geological origin would be to study the ratio of carbon-12 to carbon-13 in the gas, and compare it to figures on Earth. A high ratio would indicate a biological origin. The methane volumes found so far on Mars are insufficient for this type of experiment.

The methane detection by Curiosity confirms the presence of methane that is also observed by orbiting spacecraft at Mars, and by telescopes on Earth, but which earlier could not be found by Curiosity.

Curiosity has also detected organic compounds, chlorobenzene, in the rocks it has been drilling. This is the first detection of organics in surface materials on Mars. It's not certain whether the organic material was actually present in the original rock, or was a produced during the analysis heating process.

Comment:  The importance of these findings is that life as we know it can only exist in the presence of complex carbon structures. We may still be far from proving that life existed on Mars, but these are significant steps in the right direction.





Thursday 1 January 2015

MARS OPPORTUNITY ROVER HAS MEMORY PROBLEM

The Mars Opportunity rover has covered 26 miles since it landed on the Martian surface ten years ago. During that time it has gathered and sent back vital data. However, recent reports from Nasa indicate that Opportunity has developed a problem with the memory of its on-board computer:
http://www.bbc.co.uk/news/technology-30642548

Project manager John Callas explained that when Opportunity tries to save telemetry data to its flash memory (equivalent to a computer's hard drive) it fails, so it then writes it to the volatile memory (like a computer's RAM) instead, which gets wiped when the rover powers down. The problem has become more severe, with Opportunity resetting itself, and sometimes stopping communication with mission control altogether.

A solution is being attempted so the rover software ignores the faulty part of the flash memory, and writes instead permanently to the healthy hardware.

Comments: It will be several weeks before it is known if this works and solves the memory loss problem.