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#41 Alexa

Alexa

    Meson

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Posted 6 September 2004 - 04:13 PM

USEFUL LINKS




  • Cosmology websites and FAQ given by SFN members
  • Other sites and forums
  • Magazines, Science & Technology
  • Hot topics :-)
  • Animations ;)
  • Vary articles available on the net
======================================================================================


  • Cosmology website and FAQ given by SFN members :

Ned Wright's cosmology website and FAQ. He teaches the undergrad and graduate level courses in cosmology at UCLA and is also one of the team in charge of the WMAP satellite observing the CMB.
http://www.astro.ucla.edu/~wright/cosmolog.htm
http://www.astro.ucla.edu/~wright/cosmology_faq.html

Wendy Freedman and Michael Turner's "Measuring and Understanding
the Universe" : http://arxiv.org/astro-ph/0308418
Note : a lot of good astronomy links are graphic rather than verbal, such as images from the HST and computer animations, also Ned Wright has a calculator that lets you calculate from something's red shift how far away it is.
Here are good online cosmology calculators :
- Siobahn Morgan's :
http://www.earth.uni.edu/~morgan/aj...ogy/cosmos.html
and Ned Wright's :
http://www.astro.ucla.edu/~wright/CosmoCalc.html
Professor Murphy's online calculator(Johns Hopkins) :
http://fuse.pha.jhu.edu/support/tools/eqtogal.html

All you ever want to know about Nebulas:
http://astronomynotes.com/evolutn/s1.htm
http://blackskies.com/neb101.htm
http://observe.arc.nasa.gov/nasa/sp...h_contents.html


Here is a nice free star chart that comes out every month and it also comes with a list of objects to look for with binoculars - a large telescope: http://www.skymaps.com/

A good place for science books... Their Starry Night program is quite simple but would at least help you through the apprehensive feeling of not knowing what your look at. It also updates off the web the daily coordinates of several interesting objects each night, for locations all over the globe : http://www.whfreeman.com/astronomy/

Good place for WMAP data : http://lambda.gsfc.nasa.gov/

Trove of stuff on relativity, it helps if you know roughly what you are looking for, and keep in mind that reading it on the web sometimes mean it has not been peer reviewed. Some of the ideas in here (^that link^) are misleading, but its still a very good challenge trying to grip some of the concepts laid out : http://relativity.livingreviews.org/Forms/search.html

While at first a ghastly sight to look at the links in the light green are a good place to start surfing to try and skim some knowledge off the information superhighway! http://academics.hamilton.edu/physi.../resources.html


If you want star maps and much more for any location and time you can try the following program(A good graphics card with OpenGL driver is a must. (Geforce 4 or later) :
http://www.starrynight.com/support/...d&Submit=Search
http://www.starrynight.com/download...ownload-Win.zip (56MB)

To add stars to mag14 you can find them here. (just copy them in the right directory)
http://www.starrynight.com/en/backyardfull.shtml
You do need a serial number to make it work
You can get a 15 day trial key here:
http://www.starrynight.com/digitald...al_download.php
(if 15day's isn't long enough to test it there are places to get a less limited key)

http://www.extrasolar.net catalogue of extra solar planets including minimum mass, distance, and system
http://www.superstringtheory.com/ So what is string theory? For that matter, what the heck are elementary particles? Check out online courses. Black holes. History. Cosmology. Mathematics
http://www.bell-labs.com/org/physicalsciences/projects/darkmatter/darkmatter.html
Bell Laboratories physical sciences research

http://www.fourmilab.ch/earthview/vplanet.html

Astrophysical QuickView (AQV) - http://www.dreamscape.com/biology/

This is a collection of informative quick summaries of new press releases dealing with astrophysics, cosmology, astronomy, and space exploration.

Atlas of the Universe - http://anzwers.org/free/universe/

Contains 3D maps of the universe zooming out from the nearest stars to the scale of the Milky Way galaxy and onwards to the surrounding superclusters and out to the entire visible universe.

Bert Dekker's deep-sky pages - http://www.bert.dekker65.freeler.nl/frset_home.htm

Astro-amateurs will find several drawings and observation-reports of deep-sky objects observed through a 6 inch Newton-telescope.

BinoSky - best bets for viewing the night sky through binoculars (BinoSky) http://www.lightandmatter.com/binosky/binosky.html

A guide to the best bets for viewing the night sky through binoculars. Images and maps on consistent scales, with consistent exposures.

Brooks/Cole Astronomy Resource Center - http://www.brookscole.com/astronomy/

Links which are useful to teachers and students of astronomy.Also, an Online Studyguide for the Wadsworth text: Foudations of Astronomy, Fourth edition, by Michael Seeds.

CCD Spectroscopy at Mais Observatory - http://members.cts.com/cafe/m/mais/

This site shows what an amateur with only modest equipment can accomplish in the area of astronomical spectroscopy.

CMB Astrophysics Research Program (UC Berkeley, LBL) - http://aether.lbl.gov/

Professor George Smoot's group conducts research on the early Universe using the cosmic microwave background radiation (CMB) and other astrophysical sources. These investigations are directed towards realizing a variety of science goals regarding CMB.

http://adswww.harvard.edu/

The Astrophysics Data System (ADS) is a NASA-funded project which maintains four bibliographic databases containing more than 3.9 million records: Astronomy and Astrophysics, Instrumentation, Physics and Geophysics, and preprints in Astronomy. The main body of data in the ADS consists of bibliographic records, which are searchable through our Abstract Service query forms, and full-text scans of much of the astronomical literature which can be browsed though our Browse interface. Please note that all abstracts and articles in the ADS are copyrighted by the publisher, and their use is free for personal use only.

Extrasolar Planets Encyclopedia - http://www.obspm.fr/encycl/encycl.html

This resource, maintained by Jean Schneider (Observatoire de Paris), provides updated information about the search for extrasolar planets.
It includes a Catalog of Extrasolar Planets


http://lheawww.gsfc.nasa.gov/docs/gamcosray/legr/bacodine/gcn_main.html

The GRB Coordinates Network (used to be called BACODINE) system (1) calculates RA,Dec coordinate positions of Gamma Ray Bursts (GRB) detected with BATSE and distributes those positions around the world in real time -- a few seconds! -- so that other instruments can make follow-up observations in other wavebands while the burst is still bursting! (2) distributes locations of GRBs detected by other spacecraft. (3) distributes reports follow-up observations made by ground-based optical and radio observers.
These three functions provide a one-stop shopping network for follow-up sites and GRB researchers.


How to present rotation curves of Galaxies ? (Galaxy Rotation Curves) - http://www.equidem.de/RCAtlas/

An alternative way to present astronomical data by combining atlas and catalogue features: The Galaxy Wanted Poster. The Halpha and NII spectra of nearby spiral edge-on galaxies reveal next to their red shift velocities their individual kinetic fingerprints. Such velocity slices or rotation curves are correlated to the morphological properties of these objects. Based on a sample of 59 galaxies of the southern hemisphere a small rotation curve atlas has been compiled which allows fast comparison between visual and spectral observations.

IMSA Astrophysics Home Page (A high school course in Astrophysics) - http://www.imsa.edu/edu/astro/

This is a one-semester course that embeds technology and the use of the internet into the daily experience of the students. Course materials, assessment tools and philosophy, and curriculum documents are all provided through this site.

Interferometry Center of Excellence (ICE, JPL) - http://ice.jpl.nasa.gov/

The Interferometry Center of Excellence (ICE), at JPL, has been established to ensure the development and maintenance of a leading edge capability in optical and near-infrared interferometer astrometry and imaging.

Kepler Mission (Searching for Earth-Sized Planets) - http://www.kepler.arc.nasa.gov/

The goal of this NASA satellite mission will be to discover and characterize earth-sized planets in the habitable zone of solar-like stars.

Kharkov multi-wave station of solar monitoring (KHASSM) - http://khassm.virtualave.net/

Images from the spectroheliograph of Kharkov Astronomical Observatory (Ukraine). This station is designed to carry out a wide range of astrophysical studies of the Sun in monochromatic light.

Latest Supernovae (Supernovae in NGC/IC Galaxies) - http://www.ggw.org/asras/snimages/

Current list of observable Supernovae in NGC and IC galaxies.

Microwave Background Anisotropies - Physics - http://background.uchicago.edu

A series of online tutorials ranging from beginner to expert covering the theory of cosmic microwave background anisotropies.

Photometric redshifts (including HDF and HDFS) - http://astrowww.phys.uvic.ca/grads/gwyn/pz/

Includes a view of the Hubble Deep Fields with access to photometric redshifts of individual galaxies.

Planetary Nebulae Observer's Home Page - http://www.blackskies.com/

The web site for almost everything related to observations of Planetary Nebulae. Hundreds of images and over 1000 observing reports in addition to many special articles. Links to other PN related sites and databases.

SETI : Star Maps for visual use - http://www.memorybankinc.com/SETI.htm

Use the 68 star maps to find the location of the data you are proccessing!

SciSpy: Science Data Central - http://www.SciSpy.com/

Resource for science data collections, standards, formats, and tools with online catalog for free and commercial downloadable software, specializing in HDF and other formats

Solar Terrestrial Activity Report - http://dxlc.com/solar/

The Solar Terrestrial Activity Report has an overview of current solar activity as well as this activity's effect on Earth's geomagnetic field. The report is primarily aimed at radio listeners. Solar cycle and solar wind information is part of the report.

Space Astrometry at The University of Texas - http://clyde.as.utexas.edu/SpAstNEW/index.html

Present and future results of space astrometry carried out by researchers associated with The University of Texas McDonald Observatory and the Department of Astronomy

Sun, Moon & Earth Applet - http://www.jgiesen.de/SME/

This interactive Java applet displays the positions of sun and moon for any date, time and location on the horizon, and on a world map with day and night regions. The times of rise and setting, the declination, the Greenwich Hour Angle of sun and moon, the equation of time and more data are computed.

TOPbase at CDS : The Opacity Project (TOPbase) - http://cdsweb.u-strasbg.fr/topbase.html

TOPbase is a read-only database system specially designed for general use of the atomic data derived by the Opacity Project. It contains energy levels, f-values and photo ionization cross sections for astrophysical abundant elements.

Wavelength-Oriented Microwave Background Analysis Team (WOMBAT) - http://astron.berkeley.edu/wombat/

WOMBAT is dedicated to understanding sources of microwave foreground emission and providing the cosmology community with estimates of foreground emission as well as uncertainties in those estimates.

What color are the stars? - http://www.vendian.org/mncharity/dir3/starcolor/

Chromaticity and rgb pixel color are derived from spectra for various stellar types/classes. Providing physically motivated colors for astronomy presentations.

Wise Observatory Monthly Astronomical Calendar and Schedule - http://wise-obs.tau.ac.il/~eran/Wise/wise_calen.html

Generate Monthly Gregorian Calendar with optional Moon Phase, Julian day, Local Sidereal Time, Sun Rise, Sun Set, Moon Rise, Moon Set, Moon R.A. and Dec.
Generate Wise Observatory schedule with observer name and instrument.


X-rays from Hot Massive Stars (XMEGA) - http://lheawww.gsfc.nasa.gov/users/corcoran/xmega/xmega.html

This site is a central location for scientists interested in the problem of X-ray emission from hot, massive stars. It contains a list of current observational projects and planned observations. Schedules of currently planned X-ray observations are also included for those interested in providing ground-based coordinated observations.



______________________________________________________________________________________________


  • Other sites and forums :
Time travel Portal – an open discussion on time travel : http://timetravelportal.com/viewtopic.php?t=294
Amateur astronomy and telescope building forum:
http://www.njnightsky.com/
Futura Science Generation ; sub-forum Sciences de l’Univers (French) :
http://www.futura-sciences.com/
Agence Spatiale Européenne:
http://www.esrin.esa.it/
Etats Unis: NASA
http://www.nasa.gov
http://www.space.com/
Agence spatiale Russe http://www.rosaviakosmos.ru/english/eindex.htm

http://www.astronomytoday.com

Astronomy Today has articles on astronomy, cosmology and space exploration, with a regularly updated sky guide plus the latest space news.

David Darling's Astrobiology Page (Astrobiology) - http://www.daviddarling.info/

Astrobiology discussions, links and books. A site with a strong emphasis on astrobiology and the search for extraterrestrial life and intelligence, reflecting author David Darling current areas of interest. In addition to a description of Darling s books, including his latest work, The Extraterrestrial Encyclopedia, the site contains hundreds of links to other sites connected with astrobiology, extrasolar planets, SETI and other topics related to alien life, FAQ s, a forum and a guestbook.

UK Students for the Exploration and Development of Space (UKSEDS) - http://www.uk.seds.org/

UKSEDS is the UK's national student space society. Take a look at our web pages for more information on our activities and how to join. The web site also contains information resources related to space in the UK and around the world.

________________________________________________________________________________________



__________________________________________________________________________



  • Hot topics :
ALL ABOUT DARK ENERGY :

- Dark Energy: Astronomers Still 'Clueless' About Mystery Force Pushing Galaxies Apart, by Andrew Chaikin
http://www.space.com/scienceastronomy/astronomy/cosmic_darknrg_020115-1.html
- Astrophysics Challenged By Dark Energy Finding, By Ray Villard
http://www.space.com/scienceastronomy/generalscience/darkenergy_folo_010410.html
- Galaxies Made of Nothing? New Theory of Mysterious Dark Matter
By Robert Roy Britt
http://www.space.com/scienceastronomy/astronomy/dark_galaxies_010105-1.html
- Scientists Map Dark Matter, Prove Einstein Right, By Maia Weinstock
http://www.space.com/news/cosmic_shear_000512.html
- Scientists Closer to Solving Dark Matter Mystery, By Patricia Reaney
http://www.space.com..._matter_wg.html
- Feeling Around for Dark Matter By Matthew Fordahl -AP Science Writer
http://www.space.com/scienceastronomy/generalscience/dark_matter_000405_wg.html
- 'Groundbreaking' Discovery: First Direct Observation of Dark Matter
By Robert Roy Britt
http://www.space.com/scienceastronomy/astronomy/missing_matter_found_010322-1.html
- Understanding Dark Matter and Light Energy, By Robert Roy Britt
http://www.space.com/scienceastronomy/astronomy/dark_matter_sidebar_010105.html

ALL ABOUT BLACK HOLES :

- Black Holes Could Be Major Power Source, By Deborah Zabarenko
http://www.space.com/scienceastronomy/astronomy/blackholes_energy_wg.html
Several articles about black holes, most recent stories at top
http://www.space.com/scienceastronomy/headlines-4.html
_______________________________________________________________________

  • Animations ;) :
Note : this section should be develloped soon.

What it would look like to someone who is falling into a black hole
http://casa.colorado.edu/~ajsh/schw.shtml



Balloon universe expands then collapses
http://www.astro.ucla.edu/~wright/balloon0.html
Why the particle horizon is 3X what you naively expect based on age of universe
http://www.astro.ucla.edu/~wright/photons_outrun.html
Microlensing (gravity bends light from things behind)
http://www.astro.ucla.edu/~wright/microlensing.html
More lensing, by a cluster of galaxies
http://www.astro.ucla.edu/~wright/cluster-lensing.html
How the bumps on the Microwave Background occurred: animation of what "Equal Power on All Scales" means
http://www.astro.ucla.edu/~wright/CMB-MN-03/epas.html


_________________________________________________________________________

  • Vary articles available on the net
Here you have a good link which is a star map with the Microwave Background dipole temperature variation superimposed
http://aether.lbl.gov/www/projects/u2/

Here's some pedagogical links for cosmology:

This article by Lineweaver (he was one of the team in charge of COBE
an earlier CMB satellite observatory) The second link has a PDF version that is more readable but takes more time to download.
Lineweaver's essay has been made into a chapter of a book now in press called "The New Cosmology" (world scientific 2004)
"Inflation and the Cosmic Microwave Background"
http://nedwww.ipac.caltech.edu/leve...r_contents.html
http://arxiv.org/astro-ph/0305179

New paper of Edward Witten in latest issue of Nature
link to online copy (for subscribers) is in the 3 June post of Woit's blog
http://www.math.columbia.edu/~woit/blog/
paper involves dark energy (which is an astronomy/cosmology topic!)
and concerns dark energy, the Higgs mass, and electroweak
symmetry breaking.


http://www.astro.spbu.ru/staff/dikarev/valery/ering.html

The modeled E ring of Saturn is presented. The page is related to Cassini project, and introduces the research of the faint circumplanetary dust complexes to everybody.

Closer To Truth - http://www.closertotruth.com/topics/universemeaning/index.html

Closer To Truth television series and Web site brings together leading scientists and scholars to debate how the Universe began, and how it may possibly end.

Coded Aperture Imaging in High-Energy Astronomy - http://lheawww.gsfc.nasa.gov/docs/cai/coded.html

Information about coded aperture imaging as applied in X- and gamma-ray astronomy: - introduction to the principle - specific details about instruments of the past, present and proposed future - bibliography.

Colorado Model of the Local Interstellar Cloud (LIC) - http://casa.colorado.edu/~sredfiel/ColoradoLIC.html

This web site provides information on the the modelling of the Local Interstellar Medium (LISM) by the Cool Star Group at the University of Colorado in Boulder. A three-dimensional model of the Local Interstellar Cloud (LIC) is provided, as well as a column density calculator based on the LIC model.

Comet Observation Home Page - http://encke.jpl.nasa.gov/

Provides information on current (bright) comets including recent observations and ephemeridies. Images and light curves of current and past comets are also available

Comets and Meteor Showers - http://comets.amsmeteors.org/

This site gives the complete text to the 1988 book Meteor Showers: A Descriptive Catalog, as well as recent meteor shower observations. The site also posts a wealth of comet information from news of recent discoveries, finder charts, and ephemerides, to extensive historical information on individual comets.
There is a European mirror site.


Cosmic-Connection.com - http://cosmic-connection.com/

A resource for amateur astronomers and space enthusiasts -- worldwide. Astronomy links to international resources, current space science events, news and weather, glossaries, multi-media and educational sites for children with onsite language translation tool.
  • 0

#42 Martin

Martin

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Posted 6 September 2004 - 04:53 PM

wow
really beautiful
much more useful than when unorganized
thanks Alexa
  • 0
Loll quantum gravity SciAm
http://www.signallak...uantumJul08.pdf
cosmology SciAm
www.mso.anu.edu.au/~charley/papers/LineweaverDavisSciAm.pdf
http://www.einstein-...logy/index.html

#43 Martin

Martin

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Posted 8 September 2004 - 12:59 AM

I didn't know until today the mass of Andromeda's central BH.
http://www.space.com...day_030528.html
(link suppl. by A.)
Milkyway central BH----2.6 million solar masses
Andromeda ditto -------30 million solar masses
  • 0
Loll quantum gravity SciAm
http://www.signallak...uantumJul08.pdf
cosmology SciAm
www.mso.anu.edu.au/~charley/papers/LineweaverDavisSciAm.pdf
http://www.einstein-...logy/index.html

#44 Martin

Martin

    Physics Expert

  • Resident Experts
  • 4,596 posts
  • LocationSF Bay Area

Posted 20 September 2004 - 02:03 AM

This just came out today.
It looks like a good up-to-date introduction to cosmology.
the field is developing fast, so it needs frequent rewriting of
textbook type stuff.
This could be a useful resource because this guy Julien Lesgourges organizes his thoughts clearly and simply---I like his writing style.
See if you agree. Also he has lots of diagrams.
And it really is for undergrads who have not yet had a course in Gen Rel.

http://arxiv.org/abs/astro-ph/0409426
An overview of Cosmology
Julien Lesgourgues
Lecture notes for the Summer Students Programme of CERN (2002-2004). 62 pages, 30 figures. Very basic conceptual introduction to Cosmology, aimed at undergraduate students with no previous knowledge of General Relativity


"While purely philosophical in the early times, and still very speculative at the beginning of the twentieth century, Cosmology has gradually entered into the realm of experimental science over the past eighty years. It has raised some fascinating questions like: is the Universe static or expanding ? How old is it and what will be its future evolution ? Is it flat, open or closed ? Of what type of matter is it composed ? How did structures like galaxies form ? In this course, we will try to give an overview of these questions, and of the partial answers that can be given today. In the first chapter, we will introduce some fundamental concepts, in particular from General Relativity. In the second chapter, we will apply these concepts to the real Universe and deal with concrete results, observations, and testable predictions."
  • 0
Loll quantum gravity SciAm
http://www.signallak...uantumJul08.pdf
cosmology SciAm
www.mso.anu.edu.au/~charley/papers/LineweaverDavisSciAm.pdf
http://www.einstein-...logy/index.html

#45 Alexa

Alexa

    Meson

  • Senior Members
  • 66 posts
  • Locationmaple's area

Posted 21 September 2004 - 12:31 AM

Hi Martin,

I think the place for the last link about comology is in vary section. I'll add NEW :-) for it.

I recommend PDF format. For those who want to print it, there are 62 pages.

You can learn about the Hubble law, The Universe Expansion from Newtonian Gravity, General relativity and the Friemann-Lemaître model, The curvature of space-time, Bending of light in the expanding Universe, The Friedmann law , The Standard Cosmological Model, The Hot Big Bang scenario, The Cold and Hot Big Bang alternatives, The discovery of the Cosmic Microwave Background, The Thermal history of the Universe, Dark Matter, Measuring the cosmological parameters, Age of the Universe, The Inflationary Universe, Problems with the Standard Cosmological Model, etc.

Do you think you have some time to develop the animation section, Martin ? I'm afraid, I do not have the time for it. I'm senior member on another forum and I really like the atmosphere there. I'll be around only for you as you are the only one who make me feel welcome on this forum.

Alexa
  • 0

#46 Alexa

Alexa

    Meson

  • Senior Members
  • 66 posts
  • Locationmaple's area

Posted 21 September 2004 - 12:45 AM

USEFUL LINKS


  • Cosmology websites and FAQ given by SFN members
  • Other sites and forums
  • Magazines, Science & Technology
  • Hot topics :-)
  • Animations ;)
  • Vary articles available on the net
======================================================================================


  • Cosmology website and FAQ given by SFN members :
Ned Wright's cosmology website and FAQ. He teaches the undergrad and graduate level courses in cosmology at UCLA and is also one of the team in charge of the WMAP satellite observing the CMB.
http://www.astro.ucla.edu/~wright/cosmolog.htm
http://www.astro.ucla.edu/~wright/cosmology_faq.html

Wendy Freedman and Michael Turner's "Measuring and Understanding
the Universe" : http://arxiv.org/astro-ph/0308418
Note : a lot of good astronomy links are graphic rather than verbal, such as images from the HST and computer animations, also Ned Wright has a calculator that lets you calculate from something's red shift how far away it is.
Here are good online cosmology calculators :
- Siobahn Morgan's :
http://www.earth.uni.edu/~morgan/aj...ogy/cosmos.html
and Ned Wright's :
http://www.astro.ucla.edu/~wright/CosmoCalc.html
Professor Murphy's online calculator(Johns Hopkins) :
http://fuse.pha.jhu.edu/support/tools/eqtogal.html

All you ever want to know about Nebulas:
http://astronomynotes.com/evolutn/s1.htm
http://blackskies.com/neb101.htm
http://observe.arc.nasa.gov/nasa/sp...h_contents.html


Here is a nice free star chart that comes out every month and it also comes with a list of objects to look for with binoculars - a large telescope: http://www.skymaps.com/

A good place for science books... Their Starry Night program is quite simple but would at least help you through the apprehensive feeling of not knowing what your look at. It also updates off the web the daily coordinates of several interesting objects each night, for locations all over the globe : http://www.whfreeman.com/astronomy/

Good place for WMAP data : http://lambda.gsfc.nasa.gov/

Trove of stuff on relativity, it helps if you know roughly what you are looking for, and keep in mind that reading it on the web sometimes mean it has not been peer reviewed. Some of the ideas in here (^that link^) are misleading, but its still a very good challenge trying to grip some of the concepts laid out : http://relativity.livingreviews.org/Forms/search.html

While at first a ghastly sight to look at the links in the light green are a good place to start surfing to try and skim some knowledge off the information superhighway! http://academics.hamilton.edu/physi.../resources.html


If you want star maps and much more for any location and time you can try the following program(A good graphics card with OpenGL driver is a must. (Geforce 4 or later) :
http://www.starrynight.com/support/...d&Submit=Search
http://www.starrynight.com/download...ownload-Win.zip (56MB)

To add stars to mag14 you can find them here. (just copy them in the right directory)
http://www.starrynight.com/en/backyardfull.shtml
You do need a serial number to make it work
You can get a 15 day trial key here:
http://www.starrynight.com/digitald...al_download.php
(if 15day's isn't long enough to test it there are places to get a less limited key)

http://www.extrasolar.net catalogue of extra solar planets including minimum mass, distance, and system
http://www.superstringtheory.com/ So what is string theory? For that matter, what the heck are elementary particles? Check out online courses. Black holes. History. Cosmology. Mathematics
http://www.bell-labs.com/org/physicalsciences/projects/darkmatter/darkmatter.html
Bell Laboratories physical sciences research

http://www.fourmilab.ch/earthview/vplanet.html

Astrophysical QuickView (AQV) - http://www.dreamscape.com/biology/
This is a collection of informative quick summaries of new press releases dealing with astrophysics, cosmology, astronomy, and space exploration.

Atlas of the Universe - http://anzwers.org/free/universe/
Contains 3D maps of the universe zooming out from the nearest stars to the scale of the Milky Way galaxy and onwards to the surrounding superclusters and out to the entire visible universe.

Bert Dekker's deep-sky pages - http://www.bert.dekker65.freeler.nl/frset_home.htm
Astro-amateurs will find several drawings and observation-reports of deep-sky objects observed through a 6 inch Newton-telescope.

BinoSky - best bets for viewing the night sky through binoculars (BinoSky) http://www.lightandmatter.com/binosky/binosky.html
A guide to the best bets for viewing the night sky through binoculars. Images and maps on consistent scales, with consistent exposures.

Brooks/Cole Astronomy Resource Center - http://www.brookscole.com/astronomy/
Links which are useful to teachers and students of astronomy.Also, an Online Studyguide for the Wadsworth text: Foudations of Astronomy, Fourth edition, by Michael Seeds.

CCD Spectroscopy at Mais Observatory - http://members.cts.com/cafe/m/mais/
This site shows what an amateur with only modest equipment can accomplish in the area of astronomical spectroscopy.

CMB Astrophysics Research Program (UC Berkeley, LBL) - http://aether.lbl.gov/
Professor George Smoot's group conducts research on the early Universe using the cosmic microwave background radiation (CMB) and other astrophysical sources. These investigations are directed towards realizing a variety of science goals regarding CMB.

http://adswww.harvard.edu/
The Astrophysics Data System (ADS) is a NASA-funded project which maintains four bibliographic databases containing more than 3.9 million records: Astronomy and Astrophysics, Instrumentation, Physics and Geophysics, and preprints in Astronomy. The main body of data in the ADS consists of bibliographic records, which are searchable through our Abstract Service query forms, and full-text scans of much of the astronomical literature which can be browsed though our Browse interface. Please note that all abstracts and articles in the ADS are copyrighted by the publisher, and their use is free for personal use only.

Extrasolar Planets Encyclopedia - http://www.obspm.fr/encycl/encycl.html
This resource, maintained by Jean Schneider (Observatoire de Paris), provides updated information about the search for extrasolar planets.
It includes a Catalog of Extrasolar Planets

http://lheawww.gsfc.nasa.gov/docs/gamcosray/legr/bacodine/gcn_main.html
The GRB Coordinates Network (used to be called BACODINE) system (1) calculates RA,Dec coordinate positions of Gamma Ray Bursts (GRB) detected with BATSE and distributes those positions around the world in real time -- a few seconds! -- so that other instruments can make follow-up observations in other wavebands while the burst is still bursting! (2) distributes locations of GRBs detected by other spacecraft. (3) distributes reports follow-up observations made by ground-based optical and radio observers.
These three functions provide a one-stop shopping network for follow-up sites and GRB researchers.

How to present rotation curves of Galaxies ? (Galaxy Rotation Curves) - http://www.equidem.de/RCAtlas/
An alternative way to present astronomical data by combining atlas and catalogue features: The Galaxy Wanted Poster. The Halpha and NII spectra of nearby spiral edge-on galaxies reveal next to their red shift velocities their individual kinetic fingerprints. Such velocity slices or rotation curves are correlated to the morphological properties of these objects. Based on a sample of 59 galaxies of the southern hemisphere a small rotation curve atlas has been compiled which allows fast comparison between visual and spectral observations.

IMSA Astrophysics Home Page (A high school course in Astrophysics) - http://www.imsa.edu/edu/astro/
This is a one-semester course that embeds technology and the use of the internet into the daily experience of the students. Course materials, assessment tools and philosophy, and curriculum documents are all provided through this site.

Interferometry Center of Excellence (ICE, JPL) - http://ice.jpl.nasa.gov/
The Interferometry Center of Excellence (ICE), at JPL, has been established to ensure the development and maintenance of a leading edge capability in optical and near-infrared interferometer astrometry and imaging.

Kepler Mission (Searching for Earth-Sized Planets) - http://www.kepler.arc.nasa.gov/
The goal of this NASA satellite mission will be to discover and characterize earth-sized planets in the habitable zone of solar-like stars.

Kharkov multi-wave station of solar monitoring (KHASSM) - http://khassm.virtualave.net/
Images from the spectroheliograph of Kharkov Astronomical Observatory (Ukraine). This station is designed to carry out a wide range of astrophysical studies of the Sun in monochromatic light.

Latest Supernovae (Supernovae in NGC/IC Galaxies) - http://www.ggw.org/asras/snimages/
Current list of observable Supernovae in NGC and IC galaxies.

Microwave Background Anisotropies - Physics - http://background.uchicago.edu
A series of online tutorials ranging from beginner to expert covering the theory of cosmic microwave background anisotropies.

Photometric redshifts (including HDF and HDFS) - http://astrowww.phys.uvic.ca/grads/gwyn/pz/
Includes a view of the Hubble Deep Fields with access to photometric redshifts of individual galaxies.

Planetary Nebulae Observer's Home Page - http://www.blackskies.com/
The web site for almost everything related to observations of Planetary Nebulae. Hundreds of images and over 1000 observing reports in addition to many special articles. Links to other PN related sites and databases.

SETI : Star Maps for visual use - http://www.memorybankinc.com/SETI.htm
Use the 68 star maps to find the location of the data you are proccessing!

SciSpy: Science Data Central - http://www.SciSpy.com/
Resource for science data collections, standards, formats, and tools with online catalog for free and commercial downloadable software, specializing in HDF and other formats

Solar Terrestrial Activity Report - http://dxlc.com/solar/
The Solar Terrestrial Activity Report has an overview of current solar activity as well as this activity's effect on Earth's geomagnetic field. The report is primarily aimed at radio listeners. Solar cycle and solar wind information is part of the report.

Space Astrometry at The University of Texas - http://clyde.as.utexas.edu/SpAstNEW/index.html
Present and future results of space astrometry carried out by researchers associated with The University of Texas McDonald Observatory and the Department of Astronomy

Sun, Moon & Earth Applet - http://www.jgiesen.de/SME/
This interactive Java applet displays the positions of sun and moon for any date, time and location on the horizon, and on a world map with day and night regions. The times of rise and setting, the declination, the Greenwich Hour Angle of sun and moon, the equation of time and more data are computed.

TOPbase at CDS : The Opacity Project (TOPbase) - http://cdsweb.u-strasbg.fr/topbase.html
TOPbase is a read-only database system specially designed for general use of the atomic data derived by the Opacity Project. It contains energy levels, f-values and photo ionization cross sections for astrophysical abundant elements.

Wavelength-Oriented Microwave Background Analysis Team (WOMBAT) - http://astron.berkeley.edu/wombat/
WOMBAT is dedicated to understanding sources of microwave foreground emission and providing the cosmology community with estimates of foreground emission as well as uncertainties in those estimates.

What color are the stars? - http://www.vendian.org/mncharity/dir3/starcolor/
Chromaticity and rgb pixel color are derived from spectra for various stellar types/classes. Providing physically motivated colors for astronomy presentations.

Wise Observatory Monthly Astronomical Calendar and Schedule - http://wise-obs.tau.ac.il/~eran/Wise/wise_calen.html
Generate Monthly Gregorian Calendar with optional Moon Phase, Julian day, Local Sidereal Time, Sun Rise, Sun Set, Moon Rise, Moon Set, Moon R.A. and Dec.
Generate Wise Observatory schedule with observer name and instrument.

X-rays from Hot Massive Stars (XMEGA) - http://lheawww.gsfc.nasa.gov/users/corcoran/xmega/xmega.html
This site is a central location for scientists interested in the problem of X-ray emission from hot, massive stars. It contains a list of current observational projects and planned observations. Schedules of currently planned X-ray observations are also included for those interested in providing ground-based coordinated observations.



______________________________________________________________________________________________


  • Other sites and forums :
Time travel Portal – an open discussion on time travel : http://timetravelportal.com/viewtopic.php?t=294
Amateur astronomy and telescope building forum:
http://www.njnightsky.com/
Futura Science Generation ; sub-forum Sciences de l’Univers (French) :
http://www.futura-sciences.com/
Agence Spatiale Européenne:
http://www.esrin.esa.it/
Etats Unis: NASA
http://www.nasa.gov
http://www.space.com/
Agence spatiale Russe http://www.rosaviakosmos.ru/english/eindex.htm

http://www.astronomytoday.com
Astronomy Today has articles on astronomy, cosmology and space exploration, with a regularly updated sky guide plus the latest space news.

David Darling's Astrobiology Page (Astrobiology) - http://www.daviddarling.info/
Astrobiology discussions, links and books. A site with a strong emphasis on astrobiology and the search for extraterrestrial life and intelligence, reflecting author David Darling current areas of interest. In addition to a description of Darling s books, including his latest work, The Extraterrestrial Encyclopedia, the site contains hundreds of links to other sites connected with astrobiology, extrasolar planets, SETI and other topics related to alien life, FAQ s, a forum and a guestbook.

UK Students for the Exploration and Development of Space (UKSEDS) - http://www.uk.seds.org/

UKSEDS is the UK's national student space society. Take a look at our web pages for more information on our activities and how to join. The web site also contains information resources related to space in the UK and around the world.

________________________________________________________________________________________


__________________________________________________________________________


  • Hot topics :
ALL ABOUT DARK ENERGY :

- Dark Energy: Astronomers Still 'Clueless' About Mystery Force Pushing Galaxies Apart, by Andrew Chaikin
http://www.space.com/scienceastronomy/astronomy/cosmic_darknrg_020115-1.html
- Astrophysics Challenged By Dark Energy Finding,By Ray Villard
http://www.space.com/scienceastronomy/generalscience/darkenergy_folo_010410.html
- Galaxies Made of Nothing? New Theory of Mysterious Dark Matter
By Robert Roy Britt
http://www.space.com/scienceastronomy/astronomy/dark_galaxies_010105-1.html
- Scientists Map Dark Matter, Prove Einstein Right, By Maia Weinstock
http://www.space.com/news/cosmic_shear_000512.html
- Scientists Closer to Solving Dark Matter Mystery, By Patricia Reaney
http://www.space.com..._matter_wg.html
- Feeling Around for Dark Matter By Matthew Fordahl -AP Science Writer
http://www.space.com/scienceastronomy/generalscience/dark_matter_000405_wg.html
- 'Groundbreaking' Discovery: First Direct Observation of Dark Matter
By Robert Roy Britt
http://www.space.com/scienceastronomy/astronomy/missing_matter_found_010322-1.html
- Understanding Dark Matter and Light Energy, By Robert Roy Britt
http://www.space.com/scienceastronomy/astronomy/dark_matter_sidebar_010105.html

ALL ABOUT BLACK HOLES:

- Black Holes Could Be Major Power Source,By Deborah Zabarenko
http://www.space.com/scienceastronomy/astronomy/blackholes_energy_wg.html
Several articles about black holes, most recent stories at top
http://www.space.com/scienceastronomy/headlines-4.html
_______________________________________________________________________
  • Animations ;) :
Note : this section should be develloped soon.


What it would look like to someone who is falling into a black hole
http://casa.colorado.edu/~ajsh/schw.shtml
Balloon universe expands then collapses
http://www.astro.ucla.edu/~wright/balloon0.html
Why the particle horizon is 3X what you naively expect based on age of universe
http://www.astro.ucla.edu/~wright/photons_outrun.html
Microlensing (gravity bends light from things behind)
http://www.astro.ucla.edu/~wright/microlensing.html
More lensing, by a cluster of galaxies
http://www.astro.ucla.edu/~wright/cluster-lensing.html
How the bumps on the Microwave Background occurred: animation of what "Equal Power on All Scales" means
http://www.astro.ucla.edu/~wright/CMB-MN-03/epas.html


_________________________________________________________________________

  • Vary articles available on the net
NEW :-) An overview of Cosmology, by Julien Lesgourgues
http://arxiv.org/abs/astro-ph/0409426
Here you can learn about the Hubble law, The Universe Expansion from Newtonian Gravity, General relativity and the Friemann-Lemaître model, The curvature of space-time, Bending of light in the expanding Universe, The Friedmann law , The Standard Cosmological Model, The Hot Big Bang scenario, The Cold and Hot Big Bang alternatives, The discovery of the Cosmic Microwave Background, The Thermal history of the Universe, Dark Matter, Measuring the cosmological parameters, Age of the Universe, The Inflationary Universe, Problems with the Standard Cosmological Model, etc.

Here you have a good link which is a star map with the Microwave Background dipole temperature variation superimposed
http://aether.lbl.gov/www/projects/u2/

Here's some pedagogical links for cosmology:

This article by Lineweaver (he was one of the team in charge of COBE
an earlier CMB satellite observatory) The second link has a PDF version that is more readable but takes more time to download.
Lineweaver's essay has been made into a chapter of a book now in press called "The New Cosmology" (world scientific 2004)
"Inflation and the Cosmic Microwave Background"
http://nedwww.ipac.caltech.edu/leve...r_contents.html
http://arxiv.org/astro-ph/0305179

New paper of Edward Witten in latest issue of Nature
link to online copy (for subscribers) is in the 3 June post of Woit's blog
http://www.math.columbia.edu/~woit/blog/
paper involves dark energy (which is an astronomy/cosmology topic!)
and concerns dark energy, the Higgs mass, and electroweak
symmetry breaking.


http://www.astro.spbu.ru/staff/dikarev/valery/ering.html
The modeled E ring of Saturn is presented. The page is related to Cassini project, and introduces the research of the faint circumplanetary dust complexes to everybody.

Closer To Truth - http://www.closertotruth.com/topics/universemeaning/index.html
Closer To Truth television series and Web site brings together leading scientists and scholars to debate how the Universe began, and how it may possibly end.

Coded Aperture Imaging in High-Energy Astronomy - http://lheawww.gsfc.nasa.gov/docs/cai/coded.html
Information about coded aperture imaging as applied in X- and gamma-ray astronomy: - introduction to the principle - specific details about instruments of the past, present and proposed future - bibliography.

Colorado Model of the Local Interstellar Cloud (LIC) - http://casa.colorado.edu/~sredfiel/ColoradoLIC.html
This web site provides information on the the modelling of the Local Interstellar Medium (LISM) by the Cool Star Group at the University of Colorado in Boulder. A three-dimensional model of the Local Interstellar Cloud (LIC) is provided, as well as a column density calculator based on the LIC model.

Comet Observation Home Page - http://encke.jpl.nasa.gov/
Provides information on current (bright) comets including recent observations and ephemeridies. Images and light curves of current and past comets are also available

Comets and Meteor Showers - http://comets.amsmeteors.org/
This site gives the complete text to the 1988 book Meteor Showers: A Descriptive Catalog, as well as recent meteor shower observations. The site also posts a wealth of comet information from news of recent discoveries, finder charts, and ephemerides, to extensive historical information on individual comets.
There is a European mirror site.


Cosmic-Connection.com - http://cosmic-connection.com/
A resource for amateur astronomers and space enthusiasts -- worldwide. Astronomy links to international resources, current space science events, news and weather, glossaries, multi-media and educational sites for children with onsite language translation tool.
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#47 Martin

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Posted 21 September 2004 - 01:24 AM

superb

merci
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Loll quantum gravity SciAm
http://www.signallak...uantumJul08.pdf
cosmology SciAm
www.mso.anu.edu.au/~charley/papers/LineweaverDavisSciAm.pdf
http://www.einstein-...logy/index.html

#48 Martin

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Posted 28 September 2004 - 05:11 PM

this page has some astrophysical constants given to high precision such as would be used in navigation within the solar system
http://ssd.jpl.nasa...._constants.html

in the expansion of space it is very common to have faster-than-light
recession speeds, something that often puzzles people.
A remedial or pedagogical article was written by Tamara Davis and
Charles Lineweaver to help people get used to FTL recession speeds
and to understand that there is really no contradiction of Special Relativity.
The link is sometimes useful in discussion:

Davis, Lineweaver
Expanding Confusion: common misconceptions of cosmological horizons and the superluminal expansion of the Universe
http://arxiv.org/abs/astro-ph/0310808
  • 0
Loll quantum gravity SciAm
http://www.signallak...uantumJul08.pdf
cosmology SciAm
www.mso.anu.edu.au/~charley/papers/LineweaverDavisSciAm.pdf
http://www.einstein-...logy/index.html

#49 MadIce

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Posted 29 September 2004 - 04:17 AM

Astronomers from the Institute of Astronomy (IoA) in Cambridge, England have watched a bundle of matter at the heart of a galaxy 100 million light-years away as it orbited a supermassive black hole four times on its way to being destroyed. The material was approximately the same distance as our Earth is from the Sun, but instead of taking a year, it only took a quarter of a day, because of the massive gravity of the black hole. By tracking the matter's doomed orbit, astronomers were then able to calculate the mass of the black hole: between 10 and 50 million solar masses.

Astronomers Watch a Black Hole Eat a Meal
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#50 Martin

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Posted 12 October 2004 - 05:30 PM

http://www.mpe.mpg.d...s/movie2003.mpg

timelapse photography of several stars doing
various-shaped orbits around the three-million-solar-mass hole at
the center of our Milky Way Galaxy

the higher-resolution version (which takes longer to download) is here:
http://www.mpe.mpg.de/ir/GC/index.php

thanks to Sean Carroll's "preposterous universe" blog

I think you will like this, Alexa. Hope so anyway.
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Loll quantum gravity SciAm
http://www.signallak...uantumJul08.pdf
cosmology SciAm
www.mso.anu.edu.au/~charley/papers/LineweaverDavisSciAm.pdf
http://www.einstein-...logy/index.html

#51 Alexa

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Posted 13 October 2004 - 11:43 PM

Cool !
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#52 Martin

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Posted 7 November 2004 - 05:16 AM

Cool !


Alexa, it is such a pleasure to have this organized library!
Someone called CPL Luke has just posted here at SFN about compact stars
(new kinds: quark stars, strange stars, preon stars)
so I was thinking to suggest some articles to you about that.
put them in only if you are interested and if you think they are good enough


Fridolin Weber (San Diego State University)
Strange Quark Matter and Compact Stars
http://arxiv.org/abs/astro-ph/0407155
58 figures, to appear in "Progress in Particle and Nuclear Physics"


F. Sandin
Compact stars in the standard model - and beyond
http://arxiv.org/abs/astro-ph/0410407

---here are some details about the Sandin, to be erased, or edited and used, as you think best---
16 pages, 6 figures, contribution to the 42nd course of the international school of subnuclear physics, 'How and where to go beyond the standard model', Erice, Aug. 29 - Sep. 7, 2004

In the context of the standard model of particle physics, there is a definite upper limit to the density of stable compact stars. However, if there is a deeper layer of constituents, below that of quarks and leptons, stability may be re-established far beyond this limiting density and a new class of compact stars could exist. These objects would cause gravitational lensing of white dwarfs and gamma-ray bursts, which might be observable as a diffraction pattern in the spectrum. Such observations could provide means for obtaining new clues about the fundamental particles and the origin of cold dark matter.
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Loll quantum gravity SciAm
http://www.signallak...uantumJul08.pdf
cosmology SciAm
www.mso.anu.edu.au/~charley/papers/LineweaverDavisSciAm.pdf
http://www.einstein-...logy/index.html

#53 astromark

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Posted 7 November 2004 - 09:54 AM

Thanks Alexa and Martin. Ant the web a great place. you have done a fine job of putting all this in a list for us.
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#54 Alexa

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Posted 7 November 2004 - 01:18 PM

Hi Martin,

I have to wait till we get more links to add. As you know, an up-dated version takes a lot of space.

Alexa
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#55 Guest_oookhc_*

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Posted 5 December 2004 - 04:55 AM

The following link is with collection for astronomy websites:

http://www.scienceox.../astronomy.html
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#56 Alexa

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Posted 5 December 2004 - 12:59 PM

Very interesting site. Thanks oookhc. Nice to meet you. :-)
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#57 Martin

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Posted 8 January 2005 - 05:19 PM

the question came up in another thread about our speed and direction in space
this can be analyzed into various components. the virgo cluster is falling towards the great attractor (in direction HydraCentaurus) relative to the CMB

our local group is falling towards Virgo a little bit but also mostly towards the great attractor, and the upshot is that Milky (and the rest of Local Group) are moving towards Crater (very nearly the same Hydra Cent direction) again relative to CMB

ultimately all motions are referred to the universal rest frame defined by the hubble flow (expansion of space) and for practical purposes by the CMB.

after all the little motions, like within our galaxy etc, the sun and earth have a speed and direction relative to CMB. It is 1.23 thousandths of c in the direction of Leo.
-----------------------------
the most authoritative source on this is the 1996 COBE report by Smoot et al
http://arxiv.org/astro-ph/9601151

http://arxiv.org/PS_...601/9601151.pdf

"The Dipole Observed in the COBE DMR Four-Year Data"

COBE was the first satellite to map the Cosmic Background and to measure the dipole
there is a doppler hotspot in the CMB in Leo
and 180 degrees in the opposite direction there is a doppler coldspot
The Microwave Background coldspot would be in Aquarius, I guess.

now we have WMAP satellite, which has confirmed the dipole but it has mapped finer detail too

What about this Leo direction? Would anybody like coordinates?

Astronomers use several different systems of coordinates and
COBE reported the Microwave Background hotspot in two different systems, ordinary celestial and galactic.

ordinary:(11 h 12 m, -7.22 degrees)
galactic: (264 degrees, +48 degrees)

they actually gave more decimal places and error bounds.
The speed they gave was equivalent to 1.231 +/- 0.008 thousandths of c, but I would just round it off to 1.23 thousandths.

If you want to convert between ordinary coords and
galactic coords, you can use something online at
Johns Hopkins University. Professor Murphy's online calculator.
Murphy's Galactic Gizmo
http://fuse.pha.jhu....ls/eqtogal.html

-----------------------------
If you go out to look at stars between 10 and 11 PM in
the evening then you probably can see Leo any clear evening
Feb thru May. It's where we're going. there's no destination, only
a direction. and the speed is a thousandth of light's

Here is a star map with the temperature of the Background as an overlay, showing the hotspot. So you can see the stars around Leo and a kindof contour map of temp:

http://aether.lbl.gov/www/projects/u2/

the hotspot is about 3.4 millikelvin above the average temp of the Background
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Loll quantum gravity SciAm
http://www.signallak...uantumJul08.pdf
cosmology SciAm
www.mso.anu.edu.au/~charley/papers/LineweaverDavisSciAm.pdf
http://www.einstein-...logy/index.html

#58 Martin

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Posted 24 January 2005 - 04:57 PM

I was looking thru Alexa's fine collection of links and couldnt find a history of the Galileo mission, may just have missed it, in any case here is one
http://www.planetary...ileo-jup02.html

that is a gripping account told by one of the people involved

Ophiolite gave a computer animation link for the Cassini mission
http://orbits.esa.in...ce/app/cssn.htm

and he also pointed out this Wiki article on Gravity slingshot maneuvers etc.
http://en.wikipedia....ional_slingshot

here is a tiny bit of info about the Galileo delta-V
http://www.resa.net/nasa/deltav.htm

I want to compare Galileo and Cassini.
Wiki says that Cassini, to get to Saturn, only needed about 2 km/second
(then hooked venus twice and earth once, for free deltaV)

But IIRC Galileo, to get to Jupiter, needed a send-off of 4 km/second
(then hooked venus once and earth twice, to get the rest of what it needed)

once at jupiter it needed almost nothing, one modest burn (less than 1 km/second) snagging the planet and then it used the gravity of the jovian moons to round out the orbit.

Actually Galileo JOI burn only gave 643 m/s
they approached Jupiter at 5 km/second, but because they went in deep and used Jupiter's own gravity they only needed 0.6 km/s to capture it
however then they were in a highly elliptical orbit, so they used maybe another 0.4 km/s burn plus free gravity assist of the jovian moons to round that out and reduce the period.

here is general info about jovian moons
http://galileo.jpl.n...oons/moons.html

misc. links:
a Dutch page on rocket motors
http://dutlsisa.lr.t..._motor_data.htm
http://dutlsisa.lr.t...tpropulsion.htm




about specific impulse of storable fuels
MMH/N204 has a vacuum Isp of ~333. N204/Hydrazine is slightly better at 340, but has tighter thermal restrictions

monomethyl hydrazine is safer to store, but straight hydrazine is better, both use nitrogen tetroxide as oxidizer

why did Galileo apparently take more of a sendof delta-V?

a quote about the rocket equation
Eric Weisstein's Mathworld
http://scienceworld....etEquation.html
gives it

\Delta v = u*ln(M_0/M)

where u is the exhaust velocity and M_0/M is the ratio
of the initial to the final mass

The exhaust velocity for MMH/N2O4 is about
3100 meters per second.

For JOI and maneuvering in the system suppose one allows
2000 m/s (twice what Galileo apparently got from its main engine)

2000 = 3100*ln(M_0/M)

Estimated mass ratio of about 1.9, in the 2 km/s case,

After Jupiter-capture and all the maneuvering, probe weighs about half of what it did when it left low-earth-orbit.

http://dutlsisa.lr.t..._motor_data.htm
http://fti.neep.wisc...chemRkt_99.html

for liquid hydrogen and oxygen the exhaust velocity is about 4400 meters per second

makes MMH/N2O4 look reasonably good, given that it is storable.

some grav. assist links:
http://cdeagle00.tri...omnum/flyby.pdf
http://www.go.ednet....t/gravasst.html

01031
889531
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Loll quantum gravity SciAm
http://www.signallak...uantumJul08.pdf
cosmology SciAm
www.mso.anu.edu.au/~charley/papers/LineweaverDavisSciAm.pdf
http://www.einstein-...logy/index.html

#59 Martin

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Posted 28 January 2005 - 04:32 AM

Ophiolite found this link for calculating bolide impact effects
http://www.lpl.arizo.../impacteffects/
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http://www.signallak...uantumJul08.pdf
cosmology SciAm
www.mso.anu.edu.au/~charley/papers/LineweaverDavisSciAm.pdf
http://www.einstein-...logy/index.html

#60 Martin

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Posted 11 February 2005 - 10:59 PM

Richard Batty supplied this "tour of the solar system" link

http://www.nationalg...tem/splash.html

Here are his comments, including some pointers on how to make it work and a caution:

This link takes you to a page with a nice 3D virtual tour of the solar system. You do have to down load the viscape svr plug in to run it and it requires a restart but then you can see the orbtal planes and if you click on a planet you can see the orbits of moons too, shame it takes the messing but I liked it. It may ask to use your own 3D graphics chip which worked ok for me. Hope this elps. P.S. if you get the downloading textures for the moons it seems to freeze but it just takes a bit to load up. P.PPP.P.S.S.SS A WARNING TO EPILEPTICS.Left click on space slows action to limits of program right click speedS it up to visual cortex in a blender type speeds.


I think this is an "all welcome" thread unless Alexa resumes editing it. If Alexa is around then she has done a lot of work on it and it is morally her project (I think). But otherwise everyone please post whatever links you think provide useful Astro/Cosmo information: facts, pictures, calculator programs, animations, other utilities.

Thanks Richard for the latest contribution!
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Loll quantum gravity SciAm
http://www.signallak...uantumJul08.pdf
cosmology SciAm
www.mso.anu.edu.au/~charley/papers/LineweaverDavisSciAm.pdf
http://www.einstein-...logy/index.html




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