Transcript mike-ken_transit

Mercury Transit November 8, 2006
When Worlds Align
Michael Portuesi & Ken Frank· San Francisco Amateur Astronomers
San Francisco Sidewalk Astronomers
The Sun is our Closest Star
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The Sun is 93 million
miles away from
Earth.
If you could drive a
car to the Sun, it
would take 163 years
to get there!
Other Stars are Very Far Away
If the Sun and Earth were only an inch
apart, the nearest star would still be over
four miles away…about as far from here to
the beach!
Sun
Earth
Other Stars
One inch
apart
Over 4 miles
to drive!
The Sun is Very Big
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109 Earths will fit across the Sun's surface
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Over 1 million Earths will fit inside the Sun
The Sun is Bright and Hot
SOHO (ESA & NASA) - http://sohowww.nascom.nasa.gov/
Surface of Sun:
10,000 degrees
Center of Sun:
27 million
degrees
Solar Corona at Eclipse – Paul Mortfield – http://www.backyardastronomer.com
Sun's
Corona:
2 million
degrees!
What is a Planet?
What’s the problem with Pluto? Pluto is now known as a “dwarf planet”
The new definition of planet:
1 Round (not potato-shaped)
2 Orbits the Sun
3 Doesn't “share its lane” with other objects (planets, asteroids, etc)
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New mnemonic: Mother Very Easily Makes Cucumber-Jalapeno
Sandwiches Using No Pleasant Condiments Usually
Mercury 101
Mercury can be seen as a morning
or evening star
Mercury is a small, rocky planet,
much like our Moon It is covered
with craters…lots more than the
Moon
Distance from Sun = 28,580,000
to 43,380,000 miles
Distance from Earth = 48,000,000
miles (closest approach)
Orbital Period = 87.97 Earth days
Length of day = 176 Earth days
Atmosphere = none
Magnetosphere = yes (weak)
Moons = none
In and Out/McDonalds = none
Mercury rotates slooowly
Solar System: Wed 2006 Nov 8
19:12 UT
Orbit of Earth & Mercury
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Mercury Orbit
Earth Orbit
Ascending
Node
Descending
Node
Line of
Nodes
Mercury
Orbit Inclination = 7.0°
Orbit Eccentricity = 0.21
Distance = 0.31 - 0.47 AU
Fred Espenak, NASA’s GSFC
2006 Transit of Mercury
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A 23 year old Parisian, Charles Messier
observed the 1753 transitIt was his first recorded observation!
The Mercury Transit
Where can you see it?
Solar Eclipse, seen from the Mir Space Station, 1999
Solar Eclipses
Sunspots & Mercury
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Sunspots are large
storms on the Sun's
surface
They look small, but
are bigger than the
Earth! Mercury will
look even smaller
They move as the Sun
rotates, in 27 days
Mercury Transit May 7, 2003
SOHO (ESA & NASA) - http://sohowww.nascom.nasa.gov/
Fe IX/X line, 171
Fe XII line, 195
Fe XV line, 284
He II line, 304
The false-color TRACE images were
made in ultraviolet light and show
the hot gas just above the Sun's
visible surface
View the Sun Safely!
So we can all easily
see the Transit,
please don’t touch
the telescopes.
When viewing the
Sun use only safe
filters.
Never look directly
at the Sun
To find out more interesting stuff
Join the
Membership benefits include:
Star parties X 3/month
Mt. Tam, Fremont Peak,
Yosemite trips
and more
Thanks
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Johannes Schedler www.panther-observatory.com
Paul Mortfield www.backyardastronomer.com
SOHO http://sohowww.nascom.nasa.gov/
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Fred Espenak http://sunearth.gsfc.nasa.gov/eclipse
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Thierry Legault http://www.astrosurf.com/legault
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Transition Region and Coronal Explorer http://trace.lmsal.com/
Museum of the History of Science, University of Oxford
Astronomical Society of the Pacific
http://www.astrosociety.org/index.html
Copyright
Copyright © 2006 Michael Portuesi &
Kenneth Frank. This work is licensed under
the Creative Commons AttributionNoDerivs-NonCommercial License. To view
a copy of this license, visit
http://creativecommons.org/licenses/by-nd-nc/1.0/ or send a
letter to Creative Commons, 559 Nathan
Abbott Way, Stanford, California 94305
Credits
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Photos are owned by and copyright the
original photographers as listed. They are
used here with permisssion, and licensed
under the same terms.
SOHO images are courtesy of SOHO/EIT
consortium. SOHO is a project of
international cooperation between ESA
and NASA.