Halley`s Comet Strikes Back!

Halley’s Comet
Strikes Back!
Larry Halstead
lt_halstead25@comcast.net
810-449-1357
What is a comet?
Or, better yet –
What is a comet – not?
• A comet is not a mother ship of the Galactic
Federation (e.g. comet Elenin)
A comet is not a member of
a rock & roll band
Klau Klettner / Hydra Records
A comet is not a
sign from God
The Anunciation – Fra Angelico ca 1432
A comet is not a meteor (although a
meteor may have come from a comet)
Johnpane (Holmes)
A comet IS many things.
A comet is an integral part of human history
A comet is an object of rare beauty
A comet is a potential threat
A comet is a chunk of rock and ice
orbiting the Sun
Protoplanetary Disks
ESO/L Calcada
Typical comet trajectory / tail behavior
Most comets have two tails
Hans Bernhard (Schnobby)
The Comet known as Halley
Nicholas Copernicus
• Conceived of heliocentric solar system.
• Published his work in the year of his
death (1543)
Tycho Brahe
• Understood Copernican
model.
• Official astronomer of the
Holy Roman Empire
• Died in 1601.
Joe Huber
Johannes Kepler
• Born in 1571.
• Worked with Tycho Brahe and
succeeded him as Imperial
Astronomer and
mathematician of the Holy
Roman Empire.
• Survived political upheaval
and personal tragedy in
Austria.
• Used Tycho’s observations to
develop laws of planetary
motion.
NASA
Kepler’s Laws of Planetary Motion
Planets orbit in an
elliptical path
PERIHELION
SUN AT 1 FOCUS
T
T
That path sweeps out
equal areas during
equal times.
Kepler’s Laws (continued)
• The ratio defined by
(time to complete one orbit)2
(average distance to the Sun)3
is a constant.
• This number is constant for each orbiting system
• Note that mass is not included.
Mass change does not affect the orbit
NASA / ESA
Isaac Newton
• Born in 1642.
• Revolutionized optics. He
thought of light as
“corpuscles” moving
through an “aether” 1666.
• Invented calculus (in
parallel with Leibniz) 1666.
• Wrote Laws of Classical
Mechanics (Principia 1687)
at the insistence of Halley.
• Wrote Law of Universal
Gravitation.
Edmond Halley
• Born in England in 1656.
• MA at Oxford, Fellow of the
Royal Society, second
Astronomer Royal of
England.
• Happily married to Mary
Took, they raised 3 children.
• Attempted to date the ruins
at Stonehenge.
• Initiated actuarial science
and demography.
Edmond Halley (continued)
• Discussed proof of Kepler’s Laws
with Newton.
• Newton had found the solution
years earlier, but had never
published his results (!!?!?!).
• Outlived his theological enemies at
Oxford, appointed as professor and
Astronomer Royal.
• Concluded that sightings in 1456,
1533, 1607, and 1682 were actually
the same comet.
• Predicted its return in 1758, but did
not live to see it (died in 1742).
Notable Halley Historical Sightings
• 466 BC – recorded by
Greeks
• 240 BC - Chinese
Empress died
• 164 BC, 87 BC –
recorded by
Babylonians
• 11 BC, 66 AD – closest to
Christ’s lifetime
• 451 AD – fall of Attila the
Hun
• 684 AD – accompanied by
3 months of rain and
plague in Europe
(Nuremburg Chronicles)
• 1066 – forecast of doom for King Harold, and of
victory for William the Conqueror at the Battle
of Hastings (Bayeux Tapestry)
• 1145 – sketched by
Canterbury Cathedral
monk Eadwine in his
psalter
• Text shown:
“Concerning the star
‘comet’. The star
‘comet’ has a ray such
as this, and in English it
is called the long-haired
star. It appears rarely
during the course of
many years, and then
as a portent.”
• 1222 – may have
encouraged
Genghis Khan to
invade Europe
• 1301 – inspired
Giotto in his
“Adoration of the
Magi”
• 1456 – Provided the basis for illustration of
plagues in Europe as documented in the
Lucerne Chronicles (Schilling, 1513)
• 1533 – Henry VIII
marries Anne
Boleyn, and is
excommunicated
by Clement VII
• 1607 –English settlers
(including John Smith)
land and establish a
colony at Jamestown,
Virginia
• 1456, 1533, 1607, 1682 –
used by Halley to predict
next appearance in 1758.
• 1759 - actual appearance
of Halley’s prediction
reached perihelion in
March
• 1835 – perihelion 2
weeks prior to Mark
Twain’s birth
• 1910 – perihelion 1
day prior to his death
“I came in with Halley's comet in 1835. It is
coming again next year, and I expect to go out
with it. It will be the greatest disappointment of
my life if I don't go out with Halley's comet. The
Almighty has said, no doubt: 'Now here are
these two unaccountable freaks; they came in
together, they must go out together.” Ca 1909
• 1910 - world wide panic
initiated by the
announcement that
cyanogen was found in the
spectroscopic analysis of the
tail.
– Earth was expected to pass
through the tail.
– Poisoning of “all life on Earth”
predicted.
– Run on gas masks
ESO
• 1986 Most recent (dimmest on record) sighting
• 2003 observed by ESO at 2.6 billion miles distance
• 2061 Next expected sighting
Orbit of Halley’s Comet
Graphics courtesy of Starry Night® Pro 6 Imaginova® Corp.
Graphics courtesy of Starry Night® Pro 6 Imaginova® Corp.
Nucleus of Halley’s Comet as imaged
by Giotto probe in 1986
Copyright 2000–2008 © European Space Agency. All rights reserved.
Modern Information
• Halley is a “short period” comet (orbital period
less than 200 years)
• There are over 500 short period comets
documented.
• There are over 120 known non-periodic comets.
• We keep finding new ones.
• It is not unusual to see 10 visual comets in a year.
• There are currently about 80 known comets in
the evening sky in Florida, perhaps 3 are visible
using a good amateur telescope.
2013 – a good year for comets
• Two comets are expected to be visible to the
naked eye in 2013.
• They are both too dim to see now.
• Comet PAN–Starrs: Mid March to mid April.
• Comet ISON: Early November to late
December.
• Best seen with binoculars.
Where to look
Comet PAN Starrs: Mar
12, 2013 @ 8:10 PM
looking west
Comet ISON: Nov 26,
2013 @ 8:38 AM
looking east
Graphics courtesy of Starry Night® Pro 6 Imaginova® Corp.
Photo Credits
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•
•
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{{Information |Description={{en|1=Bill Haley and his Comets during a TV-appearance.}}
{{de|1=Bill Haley and his Comets während eines Fernsehauftrittes.}} |Source=This image was
provided with the friendly permission by Mr. Klau Klettner from Hydra Records
{{Information |Description=Comet 17P/Holmes 19-night composite with constellation stick
figure |Source=self-made |Date=2007-10-25 to 2008-03-09 |Author= Johnpane |Permission=
|other_versions=[Image:17P Holmes composite JPane.jpg] |attrib
{{Information |Description={{en|1=Comet Hale-Bopp over Munich. Analog photo with 1:4 /
f=300mm, converted with NIKON D90}} |Source={{own}} |Author=Hans Bernhard (Schnobby)
|Date=1997 |Permission={{Ingeborg Bernhard permission}} |
{{Non-free image data |Description = The nucleus of Halley's Comet, taken by the Giotto
probe in 1986 |Source = http://www.esa.int/esaSC/120392_index_1_m.html#subhead6
|Portion = All |Low_resolution = Yes. 292x300 pix (free of charge for educational or
informational purposes. – fair use license)