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Astronomy notes

skylights news Constellation & star list The Constellations & their stars by month constellations

Aurora Borealis

Aurora Borealis poker flat research range - alaska (prediction, forecasts, alerts and info) forecast map

Aurora Borealis (I saw something Oct 25 2001, Dublin) Alaska Science Aurorea substorm pfrr aurorea FAQ About.com aurorea FAQ about.com Aurorea Borealis ireland aurora pictures

SOHO: The Solar and Heliospheric Observatory gallery archive summary latest

asteroids, comets, meteors

leonids prediction 2004 (from east antrim astro soc) Temple-tuttle & leonids, Nov 17th every year

By Toutatis

toutatis (one of Asterix & Obelix's favourite gods) the asteroid came close end this(2004) sep. It's a mad object. Weird shape, eccentric orbit, ?chaotic?weird rotation. nasa_4179_Toutatis The sky didn't fall on our heads! cnn

YourSky utility starmaps Dublin Amsterdam Paris
Now UT
Latitude: North South Longitude: East West Set for nearby city
Ecliptic and equator
Moon and planets
Deep sky objects of magnitude and brighter
Constellations: Outlines
Names aligned with horizon?
Boundaries
Stars:
Show stars brighter than magnitude Names for magnitude and brighter
Bayer/Flamsteed codes for and brighter
Invert North and South
Image size: pi
Colour scheme:

Astronomical Imaging astroimage: Dublin, 05/01/2000 20:00

Moon and Planets

Comprehensive Luna
seds nine planets

Jupiter orbit: 778,330,000 km (5.20 AU) from Sun diameter: 142,984 km (equatorial) mass: 1.900e27 kg

main satellites: (Galilean satellites 1610) 
1:2:4:8 orbit lock (almost - excepting Callisto)

      .        .        .        o              .
      C        G        Io                      E

           Distance  Radius    Mass
Satellite  (000 km)   (km)     (kg) 
---------  --------  ------  -------
Io              422    1815  8.94e22
Europa          671    1569  4.80e22
Ganymede       1070    2631  1.48e23
Callisto       1883    2400  1.08e23
(jan 5 2000 16:20ish)

Saturn orbit: 1,429,400,000 km (9.54 AU) from Sun diameter: 120,536 km (equatorial) mass: 5.68e26 kg

VSOP87 planetary theory. This theory was developed back in the mid and late 1980's by astronomers (Bretagnon, Chapront, Chapront-Touze, Laskar, Simon, Morando to name a few) at the Bureau des Longitudes in Paris, France. The object of their research was to develop a set of closed-form analytical formulas, similar to those previously developed by astronomers such as Simon Newcomb, that accurately describes the motions of the Sun, Moon, and planets. Their model included standard Newtonian gravitational interactions, which are very well understood both physically and mathematically, and relativistic effects that the older mathematical theories neglected because these effects were, at the time, unobservable. The actual numbers you see in Meeus' book are derived from the process of making the mathematical model match values (coordinates) given by brute force numerical integration of the rigorous relativistic equations of motion. These numerical integrations are carried out most notably at the Jet Propulsion Laboratory (JPL) in California and they are the most accurate way of modeling planetary motions. However, the integrations are not in the most directly useful form for amateur astronomers to use whereas a cut-and-dried formula in which you plug in the time and out pops the answer IS more directly useful.

Because the VSOP87 theory (and the similar ELP2000 lunar theory which describes the Moon's motion) is calibrated to the JPL ephemerides, the VSOP87 is no more accurate than the JPL ephemerides are and really only suffices for optical observations. Nevertheless, the VSOP87 theory and its more recent cousins serve a useful purpose for programmers.

Book, PRACTICAL EPHEMERIS COMPUTATIONS, Joe Heafner, describes (among other things) the JPL ephemerides and provides software in both PowerBasic and ANSI C for using the JPL ephemeris data files. Both my book and a CD-ROM with the JPL data are available from the publisher, Willmann-Bell, Inc..

Stars!

skylights news Constellation & star list The Constellations & their stars by month constellations From constellations by month For month's after best seen an hour later. For month's before best seen an hour earlier. In ireland (which objects can we not see? Below declination x.

Constellations

Ursa Major

 +    +                    1    2
        +  .      +               3  4      5
                                            
            +    +                    6    7

Name, class, distance (light years), RA, Declination, Magnitude

Andromeda Galaxy

astronomy.ie Temple-tuttle & leonids, Nov 17th every year astro link list Irish Physics departments nightskyobserver.com (an Irish page too?)

Satellite observing

In evenings and morning as they are visible only when out of earth's shadow. Official UTC time

Satellite info from heavens-above.com: Observing Satellites intro Brightest Satellite list for today Select Satellite
ISC: Dublin times info
MIR: Dublin times info (er ... yes, MIR is gone)
Iridiums Iridium flares, 7 day

skychart

Software - web linux palm windows

Star-Pilot (for palmpilots)

fourmilab.ch Home-Planet astro software for Windoze YourSky astro webserver (Dublin is roughly 53deg 12 min N, 6deg 6min W.)

sterrenwacht and Java daily astronomical event calculator "Astronomical Algorithms" by Jean Meeus.

Vernal equator & poles in line withe earth's equator & poles. Polaris, ... Definitions of Right Ascention (point on vernal equator where rises?) and declination

Tides/weather

sailing.html www.meto.govt.uk aertel/p162.htm Dub tides Cobh tides sunrise.html Tide forms, kind of make a mess of Netscrape so they're moved here: tides/sunset/whatever JavaScript Guide Earth Viewer (to get lat/long) cities Dublin: 5312'N 66'W (15 degree width)

stuff

SEDS Students Exploring & Discovering Space
Dark Sky
Sky & Telescope Magazine links Space Imaging

GPS howstuffworks USNO utexas What does Dublin look like from a GPS satellite then? :) GPS view 2200k above, well I think there at 55degree orbits but it's close enough. And from the top of the troposphere 200k above

Lat/Long listings

Astrodienst Astrology :-7 Cobh mapblast Cobh Astronomic Clock shareware someone on usenet sci.astro ngc0908 ngc1300 ngc2207

What is?

celestial co-ordinates Declination (degrees & minutes) == latitude Right ascention (hours), a star of ra=0 (on the meridian) at midnight on september 21, is due south. 1 hour right ascention = 15 degrees east