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  • Over the past 10 years there hasbeen a marked increase in mis- sion proposals to both ESA and NASA where the main scientific objective has been to advance our understanding of the basic laws of physics, rather than to learn how that physics is applied in astro- physical systems or the universe at large. As such these missions are not appropriate for review by commit- tees assessing either astrophysics or solarâterrestrial physics as the mis- sion aims and interested communi- ties are rather different. This has been appreciated by ESA and NASA who both have disciplines called âFundamental Physicsâ, and several other space agencies have now iden- tified it as a separate activity. The UK community has played a key part in promoting fundamental physics as a worthwhile space disci- pline and has heavily supported mission studies within ESA and NASA. It is at the forefront of much of the key technology devel- opment and is well placed to be part of a pioneering new discipline out of which major advances in our understanding of physics are wait- ing to come. The UK fundamental physics com- munity has produced this document to provide input to PPARC discus- sions at SSAC level with regard to the future ESA programme. Con- straints on the ESA budget are likely to force changes to its future plan and it is vital that any such changes are made with a full consideration of the scientific merits and strategic importance of the programme. The report seeks to: l inform the UK SSAC of the scien- tific potential of space missions in fundamental physics l detail the current UK interests in the science and technology of fun- damental physics missions l outline future opportunities for the UK community in fundamental physics missions worldwide l express to UK SSAC the opinion of the UK community on the ESA situation with respect to fundamen- tal physics. In summary, the report concludes that the new discipline can benefit significantly from the use of dedi- cated space missions, and ESA, NASA and COSPAR have recog- nized this by setting up their own specific subdivisions to deal with it. Interest in carrying out experiments in fundamental physics using space missions has been evident since the early 1970s, but only now is the technology mature enough to make such huge improvements in sensitiv- ity that dedicated missions have become scientifically justifiable. There is significant scientific inter- est within the UK and there has already been significant involvement by UK scientists in many mission proposals and studies. UK groups are internationally competitive and are leading the development of key technologies. UK groups are involved in every major internation- al project and could provide leader- ship roles. But fundamental physics within ESA is threatened by contin- uing financial constraints. There is a danger that ESA might contract its programme at the expense of this new exciting discipline. The report concludes with the fol- lowing recommendations to PPARC/BNSC: l to support the cause of funda- mental physics within ESA l to support the continuation of STEP and LISA within the ESA pro- gramme l to support UK scientists in pur- suit of this branch of science, and to remain at the forefront of inter- national activity. It is clear that UK involvement in fundamental physics in space has a relatively long history at a substan- tial level. We are well placed to be key/leading players in many mis- sions, but consolidation of our position is now required as mis- sions move on to more advanced stages where more substantial effort is needed to maintain our roles in competition with more and more groups which are becoming inter- ested and getting involved. The UK groups interested in gravitational wave observations from space have formed the UK Space Gravitational Wave Technology Working Group (UKSGWTWG) (now renamed GravTech) which is planning and coordinating UK efforts to target the most important technologies and secure a UK lead in these areas. 3.4 June 2000 Vol 41 NEWS Fundamental physics: a new discipline Tim Sumner of Imperial College summarizes the community report on fundamental physics in Britain prepared for PPARC. The $154 million Imager forMagnetopause-to-Aurora Glob- al Exploration (IMAGE), was launched from Vandenberg Air Force Base, California on 25 March this year. IMAGE aims to obtain images that will help researchers to unravel the interactons between the solar wind and the Earthâs magnetosphere. This will be a wel- come first chance to see what the Earthâs magnetic field actually looks like. The view will extend some 75 000 km into near-Earth space, and although it will be fairly coarse in resolution compared with normal photography, it will be able to distinguish structure within the magnetosphere. Researchers at the Rutherford Appleton Laboratory (the Central Laboratory of the Research Coun- cils) are involved in the project. The satellite will use neutral atom, ultraviolet, and radio imaging tech- niques to: l identify the dominant mecha- nisms for injecting plasma into the magnetosphere on substorm and magnetic storm time scales; l determine the direct- ly driven response of the mag- neto- sphere to solar wind changes; l discover how and where magnetos- pheric plasmas are energized, transported, and subsequently lost during substorms and magnetic storms. The project uses six state-of-the- art instruments to produce images of the complex interactions between the solar wind and the Earthâs magnetosphere: l High Energy Neutral Atom imager, developed by Johns Hop- kins University Applied Physics Laboratory; l Medium Energy Neutral Atom imager, developed by SwRI; l Low Energy Neutral Atom imager, developed by Goddard; l Extreme Ultraviolet imager, devel- oped by the University of Arizona, Tucson; l Far Ultraviolet imager, developed by the University of California at Berkeley; l Radio Plasma Imager, developed by the University of Massachusetts at Lowell. These instruments will provide scientists with the first three-dimen- sional images of the major charged- particle systems in near-Earth space. The images returned by the spacecraft will provide simultane- ous measurements of the densities, energies and masses of charged par- ticles throughout the inner magnetosphere. During its two-year mission, the âphotographsâ of remote particle populations, taken every two min- utes, will be combined to make movies in real time. âIn the past, we have only been able to sample the magnetosphere from satellites,â explained Manuel Grande of RAL. âWith IMAGE we will be able to look at the entire system. By looking at the broader picture, we will be able to under- stand more about where the sam- ples came from.â IMAGE data will also be of considerable value to scientists involved in the European Space Agencyâs Cluster II mission, which is scheduled for launch in June and July. l More information about the IMAGE mission can be found at: or IMAGE looking good A successful launch of NASAâs IMAGE satellite should bring new pictures of the Earthâs surroundings to solarâterrestrial researchers, reports Peter Bond.
  • 3.5June 2000 Vol 41 NEWS The way forward Now that NASA has published its report on the latestMars mission and the dust has settled a little, it is agood chance to take stock of where space explo- ration will be going. NASA has acknowledged that the drive for faster, better and cheaper missions brought with it pres- sures on the organization that led to mistakes. With hindsight, this seems obvious. Faster, better, cheaper is a wonderful thought â exactly what we all want when it comes to a new car, computer or even research project. But the phrase has its origins in an engineerâs maxim, along the lines of you can make anything faster, better OR cheaper. Sometimes you can have two of these, but you canât have all three. It is certainly true with cars, as any car buyer can tes- tify. On the surface, computers are a different kettle of fish. Every time I buy a machine, I appear to do so days before the release of a cheaper, faster and altogether better system. But the net effect is the same as with cars: expectations change at about the same rate as the equipment improves and what was a perfectly good processor speed five years ago is laughable now. Changed expectations have something to do with the feel- ing of disillusionment at NASA. Certainly the success of some space missions such as the extraordinarily long-lived Galileo (whose latest discoveries are reported on page 29) has boosted hopes and confidence, so much so that the demise of the Compton Gamma Ray Observatory at the end of its planned life seems a failure. At times, the sheer volume and quality of results â for example the mountains of data generated by Pathfinder at Mars â provide a false sense of security, akin to that coming from shiny paintwork and clean upholstery in a car that the cheery dealer has promised will be faster, better and cheaper. You know it wonât last. Expecting more results for the same or less money just canât work. Somewhere along the line cor- ners are cut and time is the first casualty, be it time for test- ing procedures, or checking code, or time for someone to work out why a spacecraft is just that little bit off-course. NASA has done a good job in acknowledging that proce- dures and lines of communication need to improve and letâs hope that they get back on course to get more staggering results from future missions. But there is also a wider message: you canât get blood from a stone. There is no point trying to spread a limited budget too thin. Britainâs science budget is decidedly limited and there is lots to do. If the choice is between a trickle of fund- ing to every part of the subject and substantial funding â including the infrastructure, IT and staff â for a few topics, most researchers would opt for the latter, to include, of course, funding for their chosen field. The only problem, of course, is how to choose what to support and what to leave behind. There are some difficult choices ahead for British astronomy. Sue Bowler, Editor. New millimetre-wave measure-ments of the distant universe reveal that it is cosmologically flat, underwent rapid inflation after the Big Bang and is unlikely to collapse again. The data shows the structure that emerged in just 300 000 years, the precursor of the giant clusters and superclusters of galaxies that we see today. âThe structures in these images predate the first star or galaxy in the universe,â said US team leader Andrew Lange of the California Institute of Technology. âIt is an incredible triumph of mod- ern cosmology to have predicted their basic form so accurately.â The map shows temperature vari- ations over an area of roughly 1800 square degrees (the Moon is shown at the bottom right for scale). It covers 2.5% of the sky, just a fraction of the area of the maps made famous by the Cosmic Background Explorer satellite, but has an angular resolution 35 times better than the COBE map. The temperature fluctuations it records are slight, of the order of 0.0001 K on an average of 2.73 K, but enough to reinforce the inflationary theory of the universe. These fluc- tuations, developed in just 300 000 years, have evolved into the large- scale structure of the universe today, the giant clusters and super- clusters of galaxies. The microwave patterns seen reflect temperature variations in the early universe, arising from sound waves. The image is composed of patches of higher and lower tem- peratures about a degree across, close to the size predicted for a flat universe. If the universe were curved, the scale of the fluctuations would differ. The angular spectrum of the data shows a strong peak at about 1°, with a weaker peak around half a degree. This implies that the universe inflated quickly and was essentially flat by 14 bil- lion years ago. The sensitivity and resolution nec- essary for such results came from a telescope called BOOMERanG (Balloon Observations of Milli- metric Extragalactic Radiation and Geophysics), developed by an inter- national team from Britain, Cana- da, Italy and the USA. The detector was launched on a balloon from the American McMurdo Station in Antarctica, which floated 37 km up for 10 days. The million cubic metre balloon took the instrument above almost all the atmosphere and stable winds carried it round the continent. It circumnavigated the pole and landed just 50 km from its launch site. Measurements depended on a micromesh bolo- meter, reminiscent of a spiderâs web of silicon nitride that absorbed mil- limetre-wave radiation from the cosmic microwave background. The minute temperature rise that results was measured by a germani- um thermistor. BOOMERanG was so sensitive because the sensor worked at just three tenths of a degree above absolute zero. SB Temperature fluctuations in the cosmic microwave background from 300 000 years after the Big Bang. The flat primordial universe A huge balloon and the stable winds of Antarctica have combined to give a detailed picture of the Cosmic Microwave Background 0 â300 µK 300 µK
  • 3.6 June 2000 Vol 41 NEWS Astronomy in Arcadia In the objective and austere world of sciencetoday, the aesthetic quality of the surroundings of the observer is rather low down the scale of pri- orities. This unidentified engraving, discovered recently during the listing of the contents of RAS Additional Manuscript 88, depicts a different world, where scientific knowledge was one of the attributes of a gentleman of wide culture. The collection is a rich and varied assortment of newspaper cuttings, advertisements for lectures, engravings, maps, and even a mildly risqué verse about a bust of Newton, dated between about 1700 and 1850. The year of publication is given against most of the items, but unfortunately the unknown hand that assembled the collection failed to record the source of most items. This engraving could be from a magazine, or perhaps the frontispiece of a book. Entitled A rep- resentation of the Eclipse that is to happen in August 1765, it depicts gentlemen preparing to observe the partial eclipse on the 16th of that month. The telescope has no visible means of sup- port and the observers stand amid a âgarde- nesqueâ scene with trees, dogs and a lake. The hill beyond is graced by a conical monument half way up and crowned by a garden building with classi- cal pediment. The little bridge spanning an arm of the lake perhaps reflects the vogue for Chinoiserie which swept England in the mid-18th century; a sage, also vaguely Chinese in garb, stands reading at the waterâs edge. The whole reflects the 18th- century ideal of Nature as improved by art and inhabited by cultured beings. Identification of the source of this attractive scene would be welcomed! P D Hingley, Librarian of the RAS. From the RAS Archives Apology The Editor wishes to apologizefor a mistake in an equation in the report of the Roger Tayler memorial meeting last year (A&G 40 6.20). Equation 1 should have been an expression for the neu- tron/proton ratio nn/np, not for the neutron number as was printed. The correct expression is as follows: nn/np = exp(âDmc 2/kT) º exp(â2.5mec 2/kT) Appointments and awards Congratulations to J Roger PAngel, Regents Professor at the Steward Observatory, University of Arizona, who has been elected a member of the US National Acade- my of Sciences; and to Reinhard Genzel of the Max Planck Institute for Extraterrestrial Physics, Garch- ing, who is now a foreign associate. Ten years of the HST Persuade your colleagues and friends in the USA to write to you at once â but make sure it is on paper, so that you too can have some of these splendid stamps to celebrate the 10th anniversary of the HST. Issued on 10 April this year, there are five designs, featuring images of the Eagle Nebula, the Ring Nebula, the Lagoon Nebula, the Egg Nebula and Galaxy NGC 1316, all taken by Hubble. They provide an opportunity to get astronomical images out into the wider world, as well as a chance to look back over this very successful project and consider how it has changed over the years. For example, do you remem- ber that early plans called for the telescope to be brought back to Earth every five years for servicing? An award for cosmology The Peter Gruber Foundation, along with the International Congress of Distinguished Awards, has instituted the worldâs first award devoted to cosmology, with a cash prize of $150 000. The Cosmology Prize of the PeterGruber Foundation, given annually to an outstanding astronomer, cosmologist, physicist or mathematician, will recognize fundamental scientific advances that shape the way people see and comprehend our universe. The first recipient will be announced at the time of the XXIV General Assembly of the Interna- tional Astronomical Union in Man- chester, in August. The award will be formally presented for the first time on 11 November 2000, in cer- emonies at the Pontifical Academy of Sciences at the Vatican. The award recipients will be cho- sen by a distinguished advisory board which includes John Barrow of the University of Cambridge, Vera Rubin of the Carnegie Institu- tion of Washington, Sir Martin Rees of the University of Cam- bridge, Rev. Dr George V Coyne, S.J., and Owen Gingerich of Har- vard Smithsonian Center for Astro- physics. Eclipse competition won in fine style Kate Stark, of Withington GirlsâSchool in Fallowfield, Man- chester, has won the RAS competi- tion to write a newspaper about last yearâs total solar eclipse. Kateâs entry, shown in full on the RAS Web site ( 1999comp.htm#Kate), is an enter- taining and informative mix of sci- entific information, eye-witness accounts and historical detail. She has diagrams, cartoons, quotes from experts, including the RASâs own David Hughes, and interesting facts about previous eclipses, as well as local news from Cornwall. Kate has marshalled a diverse array of resources for her âkeepsake edi- tionâ of a Cornwall evening paper, for example citing a favourite Web site, and providing a cut-out-and- keep flick book showing the move- ments of the Sun and Moon. And in the interests of a plausible-look- ing paper, she has also filled in the pages with fun adverts and even written a poem about the eclipse from a cowâs point of view. All in all it is a most impressive piece of work. Congratulations! SB
Over the past 10 years there hasbeen a marked increase in mis- sion proposals to both ESA and NASA where the main scientific objective has been to advance our understanding…