challenger 51-ljanuary 28, 1986 christa mcauliffe
TRANSCRIPT
Challenger 51-L
January 28, 1986
Christa McAuliffe
“…The Challenger Crew was pulling us into the future and we will continue to
follow them.” -- President Ronald Reagan
Comet HalleyNext approach: July 2061
Comet EnckeNext approach: October 2013
Why Study Comets?Why Study Comets?
Scientific ResearchScientific Research
Prevent a comet Prevent a comet from colliding with from colliding with EarthEarth
Potential resources Potential resources for future missionsfor future missions
Comet Facts Comets are made of: Ice Rock Dust Gases
How comets get their names Named for the person
who observed the comet and analyzed its orbital path
Names assigned by the International Astronomical Union
Short period/long period < 200 years = short
period > 200 years = long
period
Anatomy of a Comet
Nucleus
Coma White Dust Tail
Blue Gas Tail
Comet Encke
Discovered by Johann Franz Encke in 1819
Orbital Period: 3.3 years
Magnitude: 7
Eccentricity: 0.8471
Mass Density: 0.6 g/cm3
0.4 to 0.9 g/cm3
none detected1.0 to 8.0 g/cm3 None- 8 to + 6
none detected0.7 to 5.4 g/cm3 0.0 to 0.3+ 4.5 to + 13.6
CO, NH3, CH4, H,
CN, CO2, O2,
N2
Less than 0.98 = short period comet
Greater than 0.98 = long period comet
- 1.7 to + 11
He2, H2, C, N2, O2 None- 15 to + 6
CO2, H2, He2, N20.7 to 5.4 g/cm3 0.0 to 0.2- 4 to + 0.7
Meteor
Asteroid
Comet
Supernova
Planet
GASESMASS DENSITY(mass per unit volume)
ECCENTRICITY(range of 0 to 1; 0 = circle)
MAGNITUDE(scale of brightness)
OBJECT
varies
NASA Comet Missions
Mission Name Launch DateGalileo October 18, 1989
Deep Space 1 October 24, 1998
Stardust February 7, 1999
Contour July 3, 2002
Rosetta March 2, 2004
Deep Impact January 12, 2005
Deep Impact/Epoxi October 11, 2010
Good Luck
On
Your Mission!
Good Luck
On
Your Mission!