Three Lectures on Astrophysics and Cosmology
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The Planck Satellite and the Cosmic Microwave Background
The Cosmic Microwave Background, Dark Matter and Dark Energy Anthony Lasenby, Astrophysics Group, Cavendish Laboratory and Kavli Institute for Cosmology, Cambridge Overview The Cosmic Microwave Background — exciting new results from the Planck Satellite Context of the CMB =) addressing key questions about the Big Bang and the Universe, including Dark Matter and Dark Energy Planck Satellite and planning for its observations have been a long time in preparation — first meetings in 1993! UK has been intimately involved Two instruments — the LFI (Low — e.g. Cambridge is the Frequency Instrument) and the HFI scientific data processing (High Frequency Instrument) centre for the HFI — RAL provided the 4K Cooler The Cosmic Microwave Background (CMB) So what is the CMB? Anywhere in empty space at the moment there is radiation present corresponding to what a blackbody would emit at a temperature of ∼ 2:74 K (‘Blackbody’ being a perfect emitter/absorber — furnace with a small opening is a good example - needs perfect thermodynamic equilibrium) CMB spectrum is incredibly accurately black body — best known in nature! COBE result on this showed CMB better than its own reference b.b. within about 9 minutes of data! Universe History Radiation was emitted in the early universe (hot, dense conditions) Hot means matter was ionised Therefore photons scattered frequently off the free electrons As universe expands it cools — eventually not enough energy to keep the protons and electrons apart — they History of the Universe: superluminal inflation, particle plasma, -
International Comet Quarterly
International Comet Quarterly Links International Comet Quarterly ICQ: Recommended (and condemned) sources for stellar magnitudes Cometary Science Center Comet magnitudes Below is a list that observers may use to evaluate whether the source(s) that they are Central Bureau for Astro. Tel. contemplating using for visual or V stellar magnitudes are recommended or not. Unfortunately, many errors have been found over the years in the both the individual variable-star charts of Minor Planet Center the AAVSO (ICQ code AC) and the AAVSO Variable Star Atlas (code AA); those variable-star EPS/Harvard charts were designed for the purpose of tracking the relative variation in brightness of individual variable stars, and they frequently are not adequately aligned with the proper magnitude scale. The new Hipparcos/Tycho catalogues have had new codes implemented (see below). New additions (and changes in categories) will be made to the following list as new information reaches the ICQ. MAGNITUDE-REFERENCE KEY Second-draft recommendation list, 1997 Dec. 1. Updated 2007 April 20 and 2017 Oct. 4. NOTE: For visual magnitude estimation of comets, NEVER USE SOURCES for which the available star magnitudes are only brighter than the comet! For example, the SAO Star Catalog is very poor for magnitudes fainter than 9.0, and should NEVER be used on comets fainter than mag 9.5. The Tycho catalogue should not be used for comets fainter than mag 10.5. (Even CCD photometrists should be wary of using bright stars for very faint comets; it is always best to use comparison stars within a few magnitudes of the comet when doing CCD photometry.) NOTE: It is highly recommended that users of variable-star charts also specify (in descriptive notes to accompany the tabulated data) the specific chart(s) used for each observation; this information will be published in the ICQ. -
People and Things
People and things Geoff Manning for his contributions Dirac Medal to physics applications at the Lab oratory, particularly in high energy At the recent symposium on 'Per physics, computing and the new spectives in Particle Physics' at Spallation Neutron Source. The the International Centre for Theo Rutherford Prize goes to Alan Ast- retical Physics, Trieste, ICTP Direc bury of Victoria, Canada, former tor Abdus Sa la m presided over co-spokesman of the UA 1 experi the first award ceremony for the ment at CERN. Institute's Dirac Medals. Although Philip Anderson (Princeton) and expected, Yakov Zeldovich of Abdus Sa la m (Imperial College Moscow's Institute of Space Re London and the International search was not able to attend to Centre for Theoretical Physics, receive his medal. Edward Witten Trieste) have been elected Hono of Princeton received his gold me rary Fellows of the Institute. dal alone from Antonino Zichichi on behalf of the Award Committee. Third World Prizes The 1985 Third World Academy UK Institute of Physics Awards of Sciences Physics Prize has been awarded to E. C. G. Sudarshan The Guthrie Prize and Medal of the from India for his fundamental con UK Institute of Physics this year tributions to the understanding of goes to Sir Denys Wilkinson of the weak nuclear force, in particu Sussex for his many contributions lar for his work with R. Marshak to nuclear physics. The Institute's on the theory which incorporates Glazebrook Prize goes to Ruther its parity (left/right symmetry) Friends and colleagues recently ford Appleton Laboratory director structure. -
Physical Cosmology," Organized by a Committee Chaired by David N
Proc. Natl. Acad. Sci. USA Vol. 90, p. 4765, June 1993 Colloquium Paper This paper serves as an introduction to the following papers, which were presented at a colloquium entitled "Physical Cosmology," organized by a committee chaired by David N. Schramm, held March 27 and 28, 1992, at the National Academy of Sciences, Irvine, CA. Physical cosmology DAVID N. SCHRAMM Department of Astronomy and Astrophysics, The University of Chicago, Chicago, IL 60637 The Colloquium on Physical Cosmology was attended by 180 much notoriety. The recent report by COBE of a small cosmologists and science writers representing a wide range of primordial anisotropy has certainly brought wide recognition scientific disciplines. The purpose of the colloquium was to to the nature of the problems. The interrelationship of address the timely questions that have been raised in recent structure formation scenarios with the established parts of years on the interdisciplinary topic of physical cosmology by the cosmological framework, as well as the plethora of new bringing together experts of the various scientific subfields observations and experiments, has made it timely for a that deal with cosmology. high-level international scientific colloquium on the subject. Cosmology has entered a "golden age" in which there is a The papers presented in this issue give a wonderful mul- tifaceted view of the current state of modem physical cos- close interplay between theory and observation-experimen- mology. Although the actual COBE anisotropy announce- tation. Pioneering early contributions by Hubble are not ment was made after the meeting reported here, the following negated but are amplified by this current, unprecedented high papers were updated to include the new COBE data. -
A Propensity for Genius: That Something Special About Fritz Zwicky (1898 - 1974)
Swiss American Historical Society Review Volume 42 Number 1 Article 2 2-2006 A Propensity for Genius: That Something Special About Fritz Zwicky (1898 - 1974) John Charles Mannone Follow this and additional works at: https://scholarsarchive.byu.edu/sahs_review Part of the European History Commons, and the European Languages and Societies Commons Recommended Citation Mannone, John Charles (2006) "A Propensity for Genius: That Something Special About Fritz Zwicky (1898 - 1974)," Swiss American Historical Society Review: Vol. 42 : No. 1 , Article 2. Available at: https://scholarsarchive.byu.edu/sahs_review/vol42/iss1/2 This Article is brought to you for free and open access by BYU ScholarsArchive. It has been accepted for inclusion in Swiss American Historical Society Review by an authorized editor of BYU ScholarsArchive. For more information, please contact [email protected], [email protected]. Mannone: A Propensity for Genius A Propensity for Genius: That Something Special About Fritz Zwicky (1898 - 1974) by John Charles Mannone Preface It is difficult to write just a few words about a man who was so great. It is even more difficult to try to capture the nuances of his character, including his propensity for genius as well as his eccentric behavior edging the abrasive as much as the funny, the scope of his contributions, the size of his heart, and the impact on society that the distinguished physicist, Fritz Zwicky (1898- 1974), has made. So I am not going to try to serve that injustice, rather I will construct a collage, which are cameos of his life and accomplishments. In this way, you, the reader, will hopefully be left with a sense of his greatness and a desire to learn more about him. -