Astronomy and astrophysics has has advanced in leaps and bounds over the past few decades. As mankind attempts to foray further into the universe, it’s the little things that get by us sometimes.

Star formation is an area that has been well researched and studied and though we understand the ‘how’ and the ‘why’ of stellar genesis and evolution; it is very difficult to get visual evidence for theoretical data.

Images of Orion Nebula - a star forming area - taken by Plank... Image credit: ESA, LFI and HFI Consortia

In our home galaxy, the Milky Way, there are an expected 100-400 billion stars. But weaving through this mass of stars are vast clouds of gas and dust that are generally referred to as the interstellar medium (ISM).

Now as much as the ISM might sound like a really cool name for dirt in space right out of Star Trek, it’s this very dust that obscures our views of new-born stars in visible light.

If we tune our instruments to look with longer wavelengths, especially where the Cosmic Microwave Background can be penetrated, lo and behold, a much clearer picture awaits us!

The dust no longer blocks the emission from the innermost regions of the galaxy and details previously unseen are revealed. New images from ESA ‘s Planck mission have revealed precisely this, isolating actual physical processes at work.

... and by Digitised Sky Survey of the same area in visible wavelength. Image credit: STScI DSS

How does Planck mapping work?

Planck maps the sky in nine frequencies using two state-of-the-art instruments, designed to produce high-sensitivity, multi-frequency measurements of the diffuse sky radiation: the High Frequency Instrument (HFI) includes the frequency bands 100 – 857 GHz, and the Low Frequency Instrument (LFI) includes the frequency bands 30-70 GHz.

The first Planck all-sky survey began in August 2009 and will be completed by late-May 2010. Planck will gather data until the end of 2012, by which time it should complete four sky scans.

At the lowest frequencies, Planck notes emissions that occur due to relativistic electrons moving at relativistic speeds that interact with the Galactic magnetic fields (also known as synchrotron emissions), and that of free-free emission arising from electrons interacting with hot gas (they are called ‘free-free’ emissions as the electrons remain free even after they cause emission of a photon.).

At intermediate frequencies (corresponding to wavelengths of a few millimetres), the emission are mainly thermal emission of ionised gas heated by newly-formed hot stars.

At the highest frequencies, Planck maps the distribution of interstellar dust, including the coldest compact cores in the final stages of collapse towards the formation of new stars.

A star is made

Once stars are formed, they disperse the surrounding molecular clouds. An equilibrium between cloud collapse and dispersion regulates the number of stars that any given galaxy makes.

Various other physical phenomena influence this balance, including gravity, heating and cooling, turbulence, magnetic fields and more.

As a result of this interplay, the ISM rearranges itself into ‘phases’ which coexist side-by-side; so the molecular clouds that contain dense and cool gas and dust and the ‘cirrus’ containing more diffuse and warmer material.

The only way to accurately have data on the phases and constitutional elements of the ISM is to look at it through multiple frequencies; something that Plank can do.

As Plank can study all the mechanisms simultaneously, we can get data of all processes at the same time which is very beneficial. Also as it maps different areas; we can compare the difference seen in the ISM in a star forming area, such as the Orion Nebula with that seen in a low star formation area.

Recent images from Plank have shown us just that. For more information on the planck mission as we as star formation please visit the ESA Planck homepage.

The illustrious Hubble Space Telescope (HST) recently celebrated its 20th anniversary, bringing to light one of the most celebrated and accomplished man-made scientific instruments. On April 24 this year, the HST officially completed 20 years in orbit, making it the most successful venture that NASA and the ESA have embarked upon.

The iconic Hubble image: the Pillars of Creation. Image credit: NASA, ESA, M. Livio and the Hubble 20th Anniversary Team (STScI)

On 24 April 1990, the Space Shuttle and crew of STS-31 launched the NASA/ESA Hubble Space Telescope into a low-Earth orbit. What followed was an epic era of the HST collecting some of the most fantastic images ever seen of the entire universe. Its many discoveries have aided and abetted astronomy, astrophysics and cosmology over the years, giving us visual proof for many things that were merely theoretical in the past. It wasn’t always a smooth curve, with the primary mirror being out of focus within a few weeks from launch, broken equipment, and a Space Shuttle rescue/repair mission that was cancelled. There was even talk of not reparing equipment a few times but the Hubble team of engineers, scientists and astronauts from NASA and ESA both proved time and time again that the HST had a lot more to give. To date, Hubble has looked at over 30,000 celestial objects. Its vast archives include over half a million pictures. The most recent renovation was carried out in May 2009, making the telescope 100 times more powerful than when it was launched.

Image celebrating HST 20th Anniversary: Image of the Carina Nebula. Image credit: NASA, ESA, M. Livio and the Hubble 20th Anniversary Team (STScI)

As a part of the celebrations, NASA, ESA and the Space Telescope Science Institute (STScI) decided on commemorating the date with a stunning new image. The Hubble anniversary image highlights a small portion of one of the largest observable regions of starbirth in the Galaxy, the Carina Nebula. Towers of cool hydrogen interwoven with dust ascend from the wall of the nebula. The scene is rather evocative of Hubble’s 1995 iconic image – “Pillars of Creation” taken by Jeff Hester and Paul Scowen .This image captures the top of a pillar of gas and dust, three light-years tall, which is being eaten away by the brilliant light from nearby bright stars. The pillar is also being pushed apart from within, as infant stars buried inside it fire off jets of gas that can be seen streaming from towering peaks like arrows sailing through the air.

Another very interesting aspect of the celebration is the Hubble Pop Culture contest, being conducted by the spanking new European website for HST. It calls to people from all over the world who have enjoyed Hubble images over the years to search for the images that have made their way into culture and arts, as seen in everyday life.

Further shots of the Carina Nebula; details of the 'Cosmic Pinnacle' shown. Image credit: NASA, ESA, M. Livio and the Hubble 20th Anniversary Team (STScI)

Also, Hubble fans can post a Facebook message or use the Twitter hashtag #hst20 or get onto the Hubble website and go to the “Messages to Hubble” page. There they can add their own messages or read selections from other messages. Fan messages will be stored in the Hubble data archive along with the telescope’s many terabytes of science data. The Hubble team hope to show future scientists just how much the telescope impacted our world and showed us, with extreme clarity, the awesome beauty of our universe.

The newest edition of this cosmic compendium contains 42,000 new entries, sending the total to over a quarter of a million x-ray sources. This extensive trove of information and knowledge will allow scientists to further probe the workings of the Universe.

Supermassive galaxy cluster in the new 2XMM catalogue

The mission, launched in 1999, was not initially meant to produce this data.  XMM-Newton makes over 600 observations each year, but at any given time the object under study takes up only a small portion of the total field of view – just under 30 arc minutes (imagine an area about the size of the full Moon).

So, to make things more efficient, the search for additional x-ray sources is simultaneously carried out, with the data being accumulated in the 2XMM catalogue for future reference. On average, an extra 70 sources additional to the main object of interest are found.

“We are getting 40,000 new detections a year. The vast majority of those – 98 per cent of them – are completely unknown; they’ve never been detected before with x-rays,” said Professor Mike Watson, leader of the XMM-Newton Survey Science Centre (SSC) based at the University of Leicester. Watson’s team compiled the catalogue. “With a serendipitous catalogue, surprises are always possible,” explained XMM-Newton Project Scientist Norbert Schartel.

Some interesting and unexpected finds have shown this was good practice. In 2009, a variable hyper-luminous x-ray source was noted. At 500 solar masses, i.e. 500 times the mass of the sun, it shows all the signs of being an intermediate-mass black hole; the missing link between stellar-mass and super-massive black holes. While it is accepted that stellar-mass black holes are formed by massive stars at the end of their lifetimes, the formation process for super-massive black holes is still unclear. One school of thought suggests the mergers of intermediate-mass black holes. This XMM-Newton detection was the first solid evidence that such an intermediate class exists.

Another surprise in the cosmic ‘party bag’ was the find, in the year 2008, of the most massive galaxy cluster found in the distant Universe. At approximately 5 × 1014 solar masses,  this galaxy cluster equalled the combined mass of over a thousand large galaxies. The discovery also shed some light on the evidence for dark energy, which is what scientists believe could be the cause of the observed expansion of the Universe.

Schartel said: “The 2XMM catalogue is still, even after 10 years, producing exciting new results. It is also a key catalogue for future missions to optimise their target choices for future research. So catalogues such as this have a legacy that goes much further into the future than just current research”.

The Large Hadron Collider (LHC) at CERN reached another significant milestone yesterday at 12.06BST, achieving proton collisions at 7 trillion electron volts (TeV).

This is the highest amount of energy ever expelled in a particle accelerator under laboratory conditions (3.5 TeV per proton beam). The LHC is poised for its first long run at an energy level three and a half times higher than previously achieved with a particle accelerator.

An event as recorded by the LHC CMS experiment. Photo credit: CERN

This historic moment is the start of a two-year campaign that will hopefully help scientists make new discoveries about our Universe and better understand its very fabric.

“It’s a great day to be a particle physicist” said CERN Director General Rolf Heuer. “A lot of people have waited a long time for this moment, but their patience and dedication is starting to pay dividends.”

“With these record-shattering collision energies, the LHC experiments are propelled into a vast region to explore, and the hunt begins for dark matter, new forces, new dimensions and the Higgs boson” said ATLAS collaboration spokesperson Fabiola Gianotti. “The fact that the experiments have published papers already on the basis of last year’s data bodes very well for this first physics run.”

“We’ve all been impressed with the way the LHC has performed so far,” said Guido Tonelli, spokesperson of the CMS experiment, “and it’s particularly gratifying to see how well our particle detectors are working while our physics teams worldwide are already analysing data. We’ll address soon some of the major puzzles of modern physics like the origin of mass, the grand unification of forces and the presence of abundant dark matter in the universe. I expect very exciting times in front of us.”

There were a few minor complications earlier on in the day and it took three attempts before the machine was safely accelerating beams at 3.5 TeV. An electric perturbation, which has been seen in other accelerators, made the protection system stop the magnets as the system was set at a very high sensitivity. A repeat of September 2008 was to be avoided at all costs, and scientists preferred having the system so sensitive that it would even trigger at very small or ‘fake’ alarms.

The machine was restarted soon after and reached a rate where collisions were seen at 7 TeV. Latest reports from CERN said that the various experiments have recorded thousands of events within an hour of stable and colliding beams.

CERN will run the LHC for 18-24 months with the objective of delivering enough data from the experiments to make significant advances across a wide range of physics channels. As soon as they have “rediscovered” the known Standard Model particles, a necessary precursor to looking for new physics, the LHC experiments will start the systematic search for the Higgs boson.

“The LHC has a real chance over the next two years of discovering supersymmetric particles,” explained Heuer, “and possibly giving insights into the composition of about a quarter of the Universe.”

Following this run, the LHC will shut down for routine maintenance, and to complete the repairs and consolidation work needed to reach the LHC’s design energy of 14 TeV . Traditionally, CERN has operated its accelerators on an annual cycle, running for seven to eight months with a four to five month shutdown each year. Being a cryogenic machine operating at very low temperature, the LHC takes about a month to bring up to room temperature and another month to cool down. A four-month shutdown as part of an annual cycle no longer makes sense for such a machine, so CERN has decided to move to a longer cycle with longer periods of operation accompanied by longer shutdown periods when needed.

“Two years of continuous running is a tall order both for the LHC operators and the experiments, but it will be well worth the effort,” said Heuer. “By starting with a long run and concentrating preparations for 14 TeV collisions into a single shutdown, we’re increasing the overall running time over the next three years, making up for lost time and giving the experiments the chance to make their mark.”

Celebrated Physicst and Chemist Marie Curie

“I have no dress except the one I wear every day. If you are going to be kind enough to give me one, please let it be practical and dark so that I can put it on afterwards to go to the laboratory.” Physicist and chemist, Marie Curie.

The arena of physics has long been considered a male domain, but the reality is rather different. In a bid to show this to the world, Geneva’s CERN, the European Organisation for Nuclear Research and the US’s Fermilab – the world’s leading laboratories for particle physics – are celebrating the ever-increasing role of women in physics on International Women’s Day (IWD). This has been celebrated on 8 March each year since 1917.

“At CERN, and in particle physics the world over, talent is the only criterion that counts,” said CERN Director General Rolf Heuer, adding: “Gender, race and religion have no part to play in finding the right person for the job.”

On Women’s Day, CERN will be doing everything in its power to show how half the engineers who operate the Large Hadron Collider, the world’s most powerful particle accelerator, are women.

This, they hope, will send out a message inspiring all young women interested in technology and particle physics that they are all welcome in the field as computer scientists, engineers and physicists.

CERN is scheduling shifts so that as many women as possible will be present in the control rooms of the site at the same time, as well as to staff the IT help-desk and guide official visits.

“The fact that we can do this easily may come as a surprise to those who don’t know us better,” said Heuer, “but it’s no surprise to me. Curiosity, the main prerequisite for being a researcher, is a shared characteristic of all humankind and that’s reflected in the CERN community. Men and women from all over the world come here to pursue their research, and the diversity they bring is one of our greatest assets.”

A poster exhibition has been organised with pictures and short bios of all the women involved in different experiments and these will be displayed around CERN.

The National Institute of Nuclear Physics has also sponsored a photographic exhibition titled “The Women who run the biggest machine ever built by Man”- an exhibition that has been making the rounds in many institutions in Italy and other European countries.

The exhibition was conceptualised by science journalist Elisabetta Durante, for the District of Scientific and Technological Information for Innovation, a new institution created to promote scientific culture, and photographed by CERN’s Mike Struik.

According to Durante, Mike’s role was essential to take pictures from the actual underground working environment, which is inaccessible to most people.

At Fermilab in the US, the entire month of March is being celebrated as “Women’s History Month”, through a series of events, discussions, and lunchtime lectures. They are also drawing up profiles of inspiring women from the Fermilab community, and are offering the chance to submit a profile about a deserving woman from the world of physics.

Further information:
IWD at CERN – includes video interviews with some of the women at CERN and the opportunity to watch the Control Rooms Live on the 8th of March.
“The Women who run the biggest machine ever built by Man” exhibition at the National Institute of Nuclear Physics
Women’s History Month at Fermilab.

Slider credit: CERN

Astronomers and star gazers rejoice! The International Dark Sky Association (IDA) declared Galloway Forest Park as the first Dark Sky Park in the UK on Monday 16 November 2009. The announcement, made during the International Year of Astronomy, is a great achievement as a result of 15 months of planning and coordinating audits, controls and readings from the forest park and nearby areas in a bid to boost tourism in south west Scotland.

A clear view of the sky. Picture credit: NASA

The final decision was made by the IDA, a non-governmental organisation (NGO) based in Arizona, USA. Lighting experts were brought in to make sure the standards for the IDA’s highest honor- the gold tier Dark Sky Park status – were maintained.

This requires a rating process for the sky quality meter which is best describes as a measure of the darkness of the sky in different areas worldwide.The scale extends from 0 to 25 and various locations have different readings; with the highest reading for the darkest place. For example, anywhere close to a major city would have a reading of around eight units while even a smaller town would be about 15 or 16 units on the scale. A photographer’s dark room would be 24 units. The reading for Galloway Park is 21 to 23.6 units overall, coming as close as possible to complete darkness near civilization of any sort.

Galloway Forest Park was established in 1947 on 75,000 hectares of land. It has 10 official viewing sites that are always open to the public from April to October and can be reached by foot, bike or horse. For other vehicles there is controlled access except for the two forest drives.

According to the Forestry Commission the park has 850,000 visitors each year and hopes to double the number with their new status. It is now the best place in the world for stargazing with over 7000 visible stars and views of the Milky Way and our own galaxy, which statistics show that less than 10% of people in the UK can view from their own homes. The forest also houses the Wigtownshire Astronomical Society observatory which always welcomes visitors.