Professor Richard Bower of Durham University discusses galaxies and galaxy clusters whilst at the European Week of Astronomy and Space Science with Astronomy Now editor Keith Cooper.
April 2009 Archives
At a dedicated press conference held at the European Week of Astronomy and Space Science (EWASS) yesterday, the International Year of Astronomy's Portal to the Universe - a one-stop-internet-shop for astronomy news - opened its doors to the public.
The latest Cornerstone project of the IYA, Portal to the Universe has been long awaited by journalists, scientists, teachers and members of the public alike. As well as collating astronomy news from a variety of sources, including the European Space Agency, the Royal Astronomical Society and the world's major telescopes for example, feeds from blogs and podcasts are also posted on the site along with live or near-live images of the Sun, spacecraft positions and telescope observations.
"It is clear that even in such a well-defined field as astronomy, there is much more 'information confusion' than you might think," says Project Manager Lars Lindberg Christensen. "There is a real need in the community for this kind of site, where astronomy content is gathered in one place and is easily accessible. The International Year of Astronomy 2009 seeks to bring the Universe down to Earth, and this Portal is an excellent way of achieving this. This website will provide a single entry point to stars and galaxies".
Thanks to technology such as RSS feeds, the Portal will act as a semi-automatically updating central repository of astronomy information from sources across the world. Data will be indexed and archived, providing a legacy that will long outlive the International Year of Astronomy itself.
"This release is just the beginning," says Christensen. "The project will develop with, and around, the community's needs, and lots of new features are planned, including adding resources such as educational materials, addresses for all astronomy stakeholders such as amateur clubs, planetariums and observatories."
The Portal to the Universe team encourages everyone to participate and submit RSS feeds for relevant news, images, videos, podcasts and so on. Astronomy Now has signed up; get more information on how to join at http://www.portaltotheuniverse.org/
Asteroseismology is the study of stellar interiors; a probe of the different modes of oscillations within their interiors that can be used to study the extent of a stellar core, convection, rotation, chemical composition and so on. It's a bit like how geologists use the propagation of seismic waves through the Earth to learn about the structure of our planet. In her plenary session this morning Conny Aerts (Leuven, Belgium) said that in order to improve evolutionary models of stars, asteroseismology is crucial. She said that if current stellar evolution models were totally correct, then some new exoplanets found around red giant stars, for example, should not exist, and that there was therefore still a lot of new science to be done in this exciting area of research.
Attendees at the 2009 National Astronomy Meeting were met with an 'otherworldly sight' whilst eating their lunch. The ESA Exomars engineering model, dubbed 'Bridget', was spotted leaving the EADS-Astrium tent as it tried to escape over the hill. This image was fortuitously snapped by Astronomy Now's Assistant Editor before the six-wheeled rover could get away. In reality, the craft was being steered by employees of the Stevenage-based EADS-Astrium. Bridget certainly turned everyone's heads.
Joe Lazio of the Naval Research Laboratory began his plenary talk this morning with a statement that in the 20th century we discovered our place in the Universe, but in the 21st century we are beginning to understand the Universe we inhibit. This is in part due to the fantastic array of space- and ground-based telescopes reaching deeper and deeper into our Universe, but, "the Universe is patiently waiting for our wits to grow sharper."
The Square Kilometer Array (SKA) is set to continue this theme, looking back to the Universe's transition from a largely neutral environment to a largely ionised one. Supported by other ambitious telescopes that are in various stages of development and construction such as ALMA and JWST, these telescopes will peek at the first stars and galaxies. The SKA will also use radio waves as a tool for detecting elusive gravitational waves, and will be used in the field of astrobiology to search for extrasolar planets and to study their chemistry.
Known as the 'international radio telescope for the 21st century', the SKA will have two sites: one in Australia and one in Africa, with antennas grouped into stations to provide one million square metres of aperture. It will begin its early science phase in 2017, and be fully operational at a range of frequencies by 2023.
A group of Gifted and Talented Pupils led by Mrs Tina Sherwood of the Meden School and Technology College in Nottinghamshire captivated fellow astronomers at the European Week of Astronomy and Space Science. Astronomy Now's Emily Baldwin caught up with them after their presentation.
Professor Mike Lockwood of the University of Southampton and the Rutherford Appleton Laboratory speaks to Astronomy Now editor Keith Cooper about what the quiet Sun means for those of us on Earth.
A group of Gifted and Talented Pupils led by Mrs Tina Sherwood of the Meden School and Technology College in Nottinghamshire captivated fellow astronomers at the European Week of Astronomy and Space Science.
The keen 11 and 12 year old students - Chloe Johnson, Joshua Cantrell, Laura Simpson and Niall Evans - gave mini presentations on the subject of archeoastronomy, the study of how people in the past have understood the night sky. The audience learnt how to find the pole star, as well as how the stars in Orion's belt line up perfectly with the three pyramids at Gisa. We also heard about stone circles like Stonehenge and how the stones are used as compass points and to mark from which direction the Sun rises and sets.
From scientists to journalists, after stopping for a video interview with Astronomy Now and Starlight, and to pose for photos with the Mars Rover prototype Bridget, the students joined members of the media in the EWASS press room to write up the day's events for the Newsround blog.
The team of young scientists will be repeating their presentation in a longer allocated slot at 8pm on Tuesday 28 April at The Open Dome at the Clifton Campus of Nottingham Trent University.
Conventional wisdom suggests that fast-rotating galaxies form when two galaxies of roughly equal size collide in a huge cosmic collision, which can often form ring galaxies where the core is separated from disc, or an elliptical galaxy. Thorsten Naab of the University of Munich reckons otherwise in the talk he's given at EWASS. He says that minor mergers - small galaxies colliding with larger galaxies - are more than capable instead of introducing sufficient angular momentum to speed up the rotation. Okay, big deal you might think. But consider this: the earliest galaxies ever seen, several thousand light years across, are rotating and nobody has ever been able to figure out how such young galaxies can form spinning discs. These galaxies were assembled from smaller galaxies merging with one another, and if Naab is correct, this is how they got their spin too. We can imagine the scenario wherein our Milky Way came together by swallowing up smaller galaxies and began to spin, a spin that continue to this day, 13 billion years later.
It's ironic given the gloriously sunny weather we've been blessed with this week, but the notable (some may say troubling) lack in solar activity recently has been a hot topic here at the European Week of Astronomy and Space Science. In a talk during a session called 'The Unusual (?) Solar Cycle', S Zharkov and VV Zharkova from the University of Bradford presented a talk on how unknown magnetic waves, out of phase with each other, may be capable of suppressing sunspots. When the waves intersect there occurs a maximum of solar activity, but the next intersection will occur close the equator, which may explain why there has been a lack of sunspots recently at higher altitudes. The effect driving these two fields is currently unknown. Image courtesy SOHO (NASA/ESA).
In this morning's plenary session Daniel Mueller from ESA told us that the solar wind was the weakest it has been since the start of the space age. Compared to the previous solar minimum, solar wind pressure is down 20 percent and the magnetic field is 35 percent weaker. Possible consequences of this "quiet" Sun are that the boundary of the heliosphere will move in, meaning that the Voyager spacecraft will reach interstellar space sooner than originally expected, but also that we may be subjected to a greater influx of cosmic rays. More on the Sun later! Astronomy Now's Website Editor Emily Baldwin spoke to planet-hunter extraordinaire Michel Mayor on his discovery of the lightest exoplanet to date, and the future of exoplanet research.
Following the success of the IYA's 100 Hours of Astronomy, which hosted hugely successful projects such as Around the World in 80 Telescopes, another weekend of astronomy events has been highlighted for the weekend of 23/24 October 2009.
She is an Astronomer (SIAA) is an official cornerstone project of the IYA. To celebrate the launch, women astronomers at the EWASS conference joined hands outside the ExoMars exhibition tent to replicate the striking image shown above and on the SIAA website. The original image shows some of the "women computers", women of the Harvard Observatory that counted and classified stars on photographic plates, typically taken by their male professors.
Image: artist's concept of a planet close to its star, courtesy of ESA/C Carreau.
Leicester University astronomer Jay Farihi speaks to Astronomy Now web editor Emily Baldwin on his discovery of the dusty remains of ancient solar systems around white dwarf stars.
In the second plenary session of the morning, 
Michel Mayor, the discoverer of the very first exoplanet orbiting sun-like star 51 Pegasi, reviewed the state of play in exoplanet research ahead of a press conference scheduled for later this morning where a new development in exoplanet research will be announced.
Michel Mayor, the discoverer of the very first exoplanet orbiting sun-like star 51 Pegasi, reviewed the state of play in exoplanet research ahead of a press conference scheduled for later this morning where a new development in exoplanet research will be announced. Mayor focussed on the success of discovering low mass planets, from "super-Neptunes" down to "super-Earths." The lowest mass planets discovered to date lie between 1.9 and 3 Earth masses. He also commented on the discovery of several exo-solar systems, with one system - 55 Cnc - hosting an impressive five planets. Now the focus will be to look for Earth-sized planets and twin Earths lying in the habitable zone - the region around a star where conditions are favourable for life as we know it on Earth.
The European Southern Observatory's Director General Tim de Zeeuw opened Tuesday's proceedings with a grand tour of the facilities in Chile. With 88 percent clear skies it's no wonder he referred to the Observatory as "a wonderful science machine", which receives over 1,000 proposals per semester. The Very Large Telescope alone is oversubscribed with proposals up to six times over.
Left: the beautifully desolate Paranal site with VISTA in the foreground and the VLT in the background. Image: ESO.
Coming up at EWASS on Tuesday...
...A special press conference has been called regarding an exciting new exoplanet discovery - we'll have the lowdown right here
...The She is an Astronomer website will be launched during the IYA meeting, highlighting important contributions made to astronomy by women throughout history
...Plus more blogs, interviews and news stories from the exciting world of astronomy research!
The future looks bright for exoplanet research. In this afternoon's "From brown dwarfs to exoplanets" session we learnt about various new instruments and surveys that are set to boost the exoplanet inventory. The OmegaCAM Transit Survey will start in 2010 using a new VLT Survey Telescope at Paranal Observatory which will be optimised towards detecting and characterising low-mass planets around M-dwarfs and Jupiter-sized planets in open clusters.
Instruments are also being developed to directly image extrasolar planets in a single observation, by looking at the contrast between the host star and the planet. The SPHERE instrument (Spectro-Polarimetric High-contrast Exoplanet Research) is nearly ready for the VLT and will enable detections of super-jupiters, while a design study for the ExoPlanet Imaging Camera and Spectrograph (EPICS) is underway at Oxford University for use with the E-ELT. Although it would not be ready until 2020 it could offer the ability to image Earth-sized planets.
Instruments are also being developed to directly image extrasolar planets in a single observation, by looking at the contrast between the host star and the planet. The SPHERE instrument (Spectro-Polarimetric High-contrast Exoplanet Research) is nearly ready for the VLT and will enable detections of super-jupiters, while a design study for the ExoPlanet Imaging Camera and Spectrograph (EPICS) is underway at Oxford University for use with the E-ELT. Although it would not be ready until 2020 it could offer the ability to image Earth-sized planets.
Things took a cosmic turn here at NAM during the exotic sounding session on the 'epoch of reionisation'. Basically, the early Universe was filled with a fog of opaque hydrogen, an era nicknamed the Dark Ages, which was gradually eroded away by harsh ultraviolet radiation, probably from the first giant, hot stars in the first galaxies. Trouble is, our radio telescopes are not yet sensitive to detect this hydrogen and pin down when it really began to erode away. In one talk this afternoon, Ilian Iliev of the University of Sussex described how simulations could help shed some light on the matter. His simulations showed that the first 20 million proto-galaxies began to emerge at redshift 40 (which is a stone's throw from the big bang in cosmological timescales), and the process of reionisation, in which the hydrogen fog was 'burned' away, could begin. By redshifts of 6 or 7, about 13 billion years ago, the fog had more or less all gone on large scales, which we can see in deep Hubble Space Telescope images.There's another problem though, highlighted in the talk that followed by Milan Raicevic of the University of Durham. He reckons that any workable model of the epoch of reionisation must include theories of galaxy formation. Think about it. As the ultraviolet radiation reionises the gas, it also heats it. Hot gas does not collapse well into stars and galaxies. There's potentially something of a paradox there, and we've got to figure out how the process manages to balance itself. So by learning about reionisation, we're also learning about the first galaxies!
Image: Artwork of the first stars, courtesy of NASA/WMAP Science Team.
Keith Cooper interviews Lord Drayson in the Mars tent at EWASS on the future of British astronomy.
Well, it seems they form differently, for a start; According to Allard, brown dwarfs, like stars, form from the core collapse of a gas cloud, whilst planets form from the bottom up in core accretion. Planets also have a much richer atmospheric composition, with much larger amounts of heavy elements and several convection layers. Brown dwarfs rotate rapidly and according to Allard's computer simulations, they have thick cloud cover swathing their atmospheres, full of the likes of ammonia and silicate dust. Breaks can occur in the cloud cover, resulting in variability in their brightness, not that they are very bright in the first place - their relatively low temperature (as 'cool' as 300 degrees Celsius) means they are dim and only visible at infrared wavelengths. Most astonishingly of all, they have magnetic fields likes stars, and in some cases they can be incredibly powerful: one brown dwarf, TVLM 513-46546, has been observed to flare at radio wavelengths with energies 1,000 times greater than the Sun. Who'd have thought these 'failed stars' could pack such a punch?
Image: An artist's impression of a low mass dwarf, courtesy NASA/ESA/G Bacon (STScI).
The relation of this crater (nicknamed the Spider) to the radial troughs is still sparking debate.
"Although they may look very similar, we shouldn't carry assumptions of the Moon to Mercury," says Dave Rothery of the Open University, who kicked off the Mercury session with a review of MESSENGER findings from the first two flybys of 2008. Rothery says some of the key geological results are that the innermost planet has a large core and magnetic field and is dominated by volcanic activity.
Continue reading Mercury, it's not the Moon!.
A proto-type for Exo Mars, Bridget, struts her stuff for EWASS delegates.
ExoMars will launch no earlier than 2016.
Professor Andy Fabian, President of the Royal Astronomical Society, referred to this year's European Week of Astronomy and Space Science (EWASS) as "Super-NAM" since it is incorporating the RAS National Astronomy Week and the European Astronomical Society's Joint European and National Astronomy Meeting. Attended by over 1,000 delegates, EWASS is bringing together scientists from across the globe, with around one-third of attendees from outside the UK.
In the opening ceremony of EWASS, the Minister of State for Science and Innovation, Lord Drayson, said "As a nation we should be proud of our astronomers", and mentioned specifically the UK's success in discovering exoplanets and our contributions towards determining the origins of the Universe and dark energy. In his speech he said that the UK should focus on the economic expansion of the space industry since it offers a great opportunity to create jobs and deliver tangential benefits to the public, such as developments in satellite technology, GPS and broadband, healthcare and so on.
He commented that being excited about space is just the first step, but that we need to encourage the next generation to persevere with subjects such as mathematics and science in order for young people to pursue careers that have the potential to change the world.
Drayson concluded his speech by congratulating the conference organisers on the scale and scope of the conference.
Directed at Lord Drayson, Joachim Krautter, President of the European Astronomical Society, commented that the global recession was no reason to reduce funding in astrophysics. "For the progress of mankind, basic research is indispensable," he said, and asked the Science Minister to "continue to support science in the same strong way as before."
Well, here we are at the University of Hertfordshire in Hatfield for the European Week of Astronomy and Space Science (EWASS), incorporating the Royal Astronomical Society's National Astronomy Meeting (NAM) - one of the most exciting weeks in the UK astronomical calendar.
Joining us are hundreds of astronomers converging on Hertfordshire, and early birds to the event were treated to a delightful evening reception of wine, music, comedy and astronomy, starring the many characters of TV impressionist Jon Culshaw, and hosted by Alice Williamson and Robert Priddey of Hertfordshire with musical accompaniment by the Alwyn String Quartet and Phillip Mead on the piano. The audience was entertained by the likes of Gordon Brown, Barack Obama, Tom Baker and of course Sir Patrick Moore, all courtesy of the talents of Jon Culshaw, who is apparently also a keen astronomer himself.
It was a fun evening, priming the pump for fun of a different kind over the next four days as we delve headlong into the varied areas of astronomical research, news and discoveries. We'll be posting news stories and interviews on our homepage www.astronomynow.com as well as blogging throughout the day. You can also get updates on Twitter and Facebook too!
