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Rounding
None
Decimal places
Significant figures
Mass/Radius/Period Orbit Calculation
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Orbital speed:
Escape speed (at SMA):
Eccentricity / Apoapsis / Periapsis Orbit Calculation
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Hohmann Transfer Orbit Calculation
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Initial speed:
Initial delta-v:
Final delta-v:
Final speed:
Transfer time:
Stay time:
Synodic time:
Final-initial angle at launch from 1:
Final-initial angle at launch from 2:
Synodic Period
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Synodic period:
Ringworld
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Ringworld surface area:
Ringworld mass:
Length of shadow-square segment:
Ringworld angular speed:
Shadow-square angular speed:
Ringworld rotational speed:
Shadow-square rotational speed:
Ringworld rotational period:
Shadow-square rotational period:
Ringworld tension:
Ringworld angular momentum:
Ringworld energy:
Beanstalk / Space Elevator
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Anchor (stationary) point:
Equal-area point:
Lower taper ratio:  
Upper taper ratio:  
Beanstalk mass:
Countermass:
Orbital Parameters
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Semi-major axis (a):
Semi-minor axis (b):
Maximum separation:
Minimum separation:
Eccentricity:  
Current angle:
Period:
Kemplerer Rosette
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Angular speed:
Rotational period:
Rotational speed:
Orbit Intersections
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Apapsis 1: (units as above)
Semi-major axis 1:
Apapsis 2:
Semi-major axis 2:
Intersection angle #1: (units as above)
Intersection radius #1: (units as above)
Approach angle #1: (units as above)
Co-rotating relative speed #1:
Counter-rotating relative speed #1:  
Intersection angle #2: (units as above)
Intersection radius #2: (units as above)
Approach angle #2: (units as above)
Co-rotating relative speed #2: (units as above)
Counter-rotating relative speed #2:
Relativistic Rocket 1
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Relativistic Rocket 2
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Relativistic Constant-Acceleration Rocket
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Orbital Constants of the Motion
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Inclination:
Energy:
Angular momentum:
Angular momentum _ x:  
Angular momentum _ y:  
Angular momentum _ z:  
Eccentricity:  
Periapsis:  
Apapsis:  
Direction of periapsis _ x:  
Direction of periapsis _ y:  
Direction of periapsis _ z:  
Semi-major axis:  
Semi-minor axis:  
Period:
Planetoid/Comet Impact
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[1 g/cm^3 for ice;
1.5 g/cm^3 for porous rock;
3 g/cm^3 for dense rock;
8 g/cm^3 for iron;]
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[11-20 km/s for planetoids;
30-72 km/s for comets;]
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Impact energy:
Planetary Data
Planet:
Evolution of the Universe
: [1/3 for radiation-dominated;
0 for matter-dominated;
-1/3 for curvature-dominated;
-1 for cosmological-constant-dominated;]
: (km/s)/Mpsc [25 to 150]
: [0 to 5]
Big Bang occurs if ΩΛ <
Big Bang occurs if ρvac > kg/m3
: [-10 to +10]
: kg/m3
Current age of universe: billion years
Critical density (ρc): kg/m3
Lambda critical (Λc): /m2
Critical vacuum density (ρvac,c): kg/m3
Type of universe:  
Curvature, present (1/R02): /Mpsc2
 
 
Lagrange Points
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  Position x/y Stability x/y Time Scales z Period
L1 (between 1 and 2): Unstable
L2 (beyond 2): Unstable
L3 (beyond 1): Unstable
L4/L5: Equilateral triangles
1
2
1
2
3
4
5
+
Lagrange points 1 to 5
Masses 1 and 2
Center of mass
Click to close
Roche Limit and Orbital Resonances
Central mass:
Central radius:
Orbital radius:
Particle density:
Roche coefficient (K): R_r = (K * rho_c / rho_o)^(1/3) * R_c
Central density:
Roche limit:
Flight Duration Calculator
Origin:
Destination:
Departure time: :
Arrival time: :
 
Flight time:  

Time zone information taken from the Encarta® 2000 New World Almanac.
© Copyright 1998, Helicon Publishing Ltd. All rights reserved.

Quadratic Equation
ax2 + bx + c = 0
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:
:
x1 = + i
x2 = + i
Complex Quadratic Equation
ax2 + bx + c = 0
: + i
: + i
: + i
x1 = + i
x2 = + i
Cubic Equation
ax3 + bx2 + cx + d = 0
:
:
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x1 = + i
x2 = + i
x3 = + i
Quartic Equation
ax4 + bx3 + cx2 + dx + e = 0
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x1 = + i
x2 = + i
x3 = + i
x4 = + i
Rot13
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Output: