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Planets, airplanes, birds

Planets, airplanes, birds. Requires specialized knowledge to be useful – buyer beware! Must be a true student of these with “local knowledge” Planets for navigation/steering Airplane routes Shipping lanes Birds Phosphorescence . Planets and navigation.

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Planets, airplanes, birds

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  1. Planets, airplanes, birds • Requires specialized knowledge to be useful – buyer beware! • Must be a true student of these with “local knowledge” • Planets for navigation/steering • Airplane routes • Shipping lanes • Birds • Phosphorescence

  2. Planets and navigation • Typically can use three planets for navigation – Venus, Mars and Jupiter • The rest are too dim • Useful websites • www.celnav.de/ragha.htm • www.ephemeris.com • Motions wrt stars depends on both the earth’s orbit and planet’s orbit • Hence the name: wanderers

  3. Steering by the planets • For latitude/longitude calculation, must know SHA and declination – from tables • For steering, rough positions can be used one night after the next to hold a course • Like the sun and stars, planets move westward by 1o per day • Eastward motion against background of stars at varying rates

  4. Motions of Planets • Venus – always close to the sun, never further than 30o • Morning star, evening star • Visible only up to two hours after sunset or before sunrise. • Has been mistaken for a boat or a train • Moves east against fixed background of stars • Jupiter – slow moving – roughly one sign of the zodiac per year • Mars – in between

  5. Current positions 19 Oct 08 • Jupiter • Decl: -22o 55’ , JH SHA: 73o 29’ W • Two weeks: -22o 39’, JH SHA: 71o W • Visible just after sunset • Mars • Decl: -15o 0’ , JH SHA: 141o 47’ • Two weeks: -18o , JH SHA: 130o W • Nearly hidden by sun, currently • Venus • Decl: -21o 29’, JH SHA: 121o 9’ W • Two weeks: -25o, JH SHA: 100o W • Close to the sun, next to Antares (25S, 113W) • Sun • Decl: -10o 19’, JH SHA: 155o 11’ W • Two weeks: -16o, JH SHA: 140o W

  6. Mars Sun Venus Jupiter

  7. Antares Jupiter Mars Venus Earth Snapshot of the relative positions of Jupiter, Mars, Venus Earth, Antares (distant) and the Sun now.

  8. Tonight’s sky at 6 PM facing SW Jupiter Ecliptic Venus Mars Sun Antares

  9. Retrograde motion As the earth overtakes a planet (superior retrograde) or a planet overtakes the earth, the planet temporarily appears to be moving backwards against a fixed background of stars. Retrograde motion of Mars 1997 NB – Jupiter is just coming out of retrograde

  10. Airplanes • Considerations for long distance flights • Typically follow great circle routes • Some changes in routing associated with jet stream • Fly at altitudes of 30,000 to 40,000 ft • Speeds of roughly 500 mph • Visible from contrails, or from reflections during day • Visible from nav/warning lights at night

  11. Navigation and warning lights on aircraft.

  12. New York to London

  13. Chicago to Paris

  14. San Francisco to Tokyo

  15. Comments on routes • Large population in cities in N. Hemisphere • Great circle routes tend toward high latitudes • Even over the North Pole • Avoid equatorial regions • Largely East-West directionality • Incoming flights from Europe from NE to SW • Outgoing flights more depressed – WSW to ENE • New England flights to Europe • Outgoing flights 6 PM – 9 PM • Incoming flights 12 PM-4 PM

  16. Landing/takeoffs/holding/N.A routes • Aircraft frequently make multiple turns on approach to urban airports • Still, landing/takeoffs will be approximately along lines radiating from local airports • Holding patterns – aircraft go on long oval tracks • Many N-S routes on the east and west coast • Many E-W routes in great plains, rockies.

  17. Shipping lanes • Like airplane routes, they often follow great-circle routes • However, are constrained by coastlines, canals, etc. • Pattern of shipping also constrained more by manufacturing, natural resources (e.g. oil) and population centers. • Attracting help from a passing ship is very difficult!

  18. Birds • Homing birds fly away from islands during the day and fly home to their nests at night. • Ranges vary up to 100 miles out to sea • Migratory birds like fly on certain pathways at certain times of the years • Pelagic birds wander in the open ocean

  19. Homing birds • Fly out to sea in search of food • At sunrise or sunset, they fly directly toward land • Can be used to “expand” the circle of landfinding around an island – Polynesians • Examples • Puffins • Boobies • Frigate birds • Pelicans • Don’t ignore the possibility that single birds seen far out to sea are lost!

  20. Expansion of circle of discovery of islands in Carolines

  21. Migratory birds • Can act as homing birds during the breeding season • Fly long distances during migration season • Leach’s petrel • Jaegers • Plovers

  22. Pelagic birds • Wander around the ocean – for all practical purposes, aimlessly (some migratory and homing component during breeding season) • Albatross • Storm petrel • Noddies • Tropic birds

  23. Sea birds of New England • Classic shore birds • Gulls • Cormorants • Terns • Plovers • Waterfowl • Common ducks • Eider ducks • Geese • Swans

  24. Cormorant Very common across the globe. Sits low in the water, dives for fish. Must spend time in the sun to dry wings. 25 mile limit from land

  25. Puffin Mainly found in arctic and sub arctic locations. Don’t migrate. 100 miles from land, will fly toward land at sunset and sunrise

  26. Eider duck Migrate from arctic to Cape Cod during December. Winter over Rarely seen more than 10 miles out.

  27. Herring gull Very common Seen far inland, following rivers, etc. Seen as far out as 50 miles to sea. Will return to land at dusk Mostly not migratory

  28. Laughing gull Males have black head during breeding season (June-Sept). Otherwise white. During breeding, stays within 50 miles of land. Non-breeding, called a “vagrant”.

  29. Common terns Sometimes called Sea swallows. During summer breeding months, will be within 50 miles of land. Will migrate along coast South to Florida during Winter.

  30. Piping plover Protected species During breeding season (Summer), stays within 10 miles of land. Migrates south along coast during winter

  31. Birds of the tropics • Distinctly different species found in the tropical regions (Tropic of Cancer to Tropic of Capricorn) • Many particular species related to those found further north • Noddies – related to terns • Cormorants • Pelicans

  32. Frigate bird Classic form of wings Holds feet along narrow tail. Seen up to 100 miles from land, but always returns.

  33. Boobies Cross shape of wings and beak are distinctive characteristics Like frigate birds, these are one of the better homing species for the navigator. 75 mile range from land

  34. Pelicans Big pouches under bills Found less than 25 miles from land

  35. Noddies Forked tails Members of the tern family Pelagic

  36. Tropicbird Long, thin tail Will breed near land during winter months Otherwise pelagic

  37. Sooty shearwater Hooked bill, pelagic Atlantic Ocean bird. Pelagic

  38. Storm petrel Small, short beak Pelagic Shows darting motions along water (thought to save energy in flight)

  39. Albatross Most have huge wingspan Pelagic, roaming over large sections of the oceans

  40. Other phenomena • Phosphorescence - “underwater lightning”

  41. Te Lapa, continued What is it? Some form of bioluminescence. It even has an anomaly designation – GLW11 (Geophysical luminescence over Water 11

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