Difference between revisions of "Jump Point"

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Jump Points refer to any point at which a [[JumpShip]] may initiate or resolve a "jump" through interstellar space. Traditionally, there are two jump points in a system - the zenith and the nadir of a star's gravity well (normally above and below the star's planetary system elliptic). There exist other points, called "pirate points", that a JumpShip can use, but recharging the [[Kearny-Fuchida Drive]] is more difficult and dangerous from these points.
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Jump Points refer to any point at which a [[JumpShip]] may initiate or resolve a "jump" through interstellar space. Traditionally, there are two jump points in a system - the zenith and the nadir of a star's gravity well (normally above and below the star's planetary system ecliptic). There exist other points, called "pirate points", which a JumpShip can use; these points are more difficult to calculate, increase the chance of a [[Misjump]] occuring, and increase the likelihood of being stranded alone in the event of a misjump.  However, in desperate situations or covert missions, the advantages of a speedy insertion can outweigh the inherent risks.
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Because JumpShips are equipped only with weak station-keeping drives (capable of 0.1G of acceleration at most), travel between a jump point and a destination within a star system is left to other craft, primarily [[DropShips]], which have the engines and fuel needed to make the multiday journey.  The exception are combat JumpShips or [[WarShips]] which are capable of traveling under their own power.
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== Overview ==
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A [[Kearny-Fuchida Drive]] must operate from some point in space where local gravity levels are below a certain minimum, allowing the K-F field to form properly. These points are generally referred to as "jump points".  Finding valid jump points in both the origin and destination star systems requires calculations that take into account the positions large sources of gravitational influences, such as stars and planets.
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== Proximity Points ==
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Within a star system, the biggest source of gravitational influence is the mass of star itself.  For example, Sol itself accounts for over 99.8% of the mass of the entire Terran system.  So almost all possible jump points are outside some minimum distance, the "proximity limit," from the system's star.<ref name=BS44>''BattleSpace - Rulebook'', pp. 42, 44</ref><ref name=DJOM30>''DropShips and JumpShips - Operations Manual'', pp. 28–30</ref><ref name=AT57>''AeroTech 2'', pp. 56–57</ref>  Jump points ''at'' the proximity limit, known as "proximity points," form a nearly uniform sphere that can range from about 75 gigameters for some red stars up to nearly 350 terameters for certain blue stars.<ref>''Campaign Operations'', p. 100</ref> 
  
 
== Standard Jump Points ==
 
== Standard Jump Points ==
Two standard jump points exist - the zenith ("above" the star) and the nadir ("below" the star). Travel from the jump point to a planet in the system is traditionally in a straight-line from the jump point to the planet with an acceleration of 1G to a distance roughly half-way to the planet and a deceleration of 1G for the remaining distance. This is useful for crews and passengers as there's a minimal amount of time spent in zero-G and also easily acclimates them to planetary gravity.
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Calculating the location of proximity points is complicated by the motions of planets within the star system, each with their own gravitational influence.    For example, proximity points in the Terran system exist near the orbital path of the gas giant Saturn, but using a proximity point near Saturn's path requires making sure that Saturn itself is not nearby. 
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From a computational standpoint, the easiest proximity points to determine in the Terran system are those points that Saturn ''never'' passes near.  As planets tend to stay within a flattened planetary disk, the easiest proximity points to calculate are those that are "above" and "below" that disk.  These points are known as the "zenith" and "nadir" points, respectively, and are collectively known as "standard jump points."
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Standard jump points are where most civilian interstellar traffic takes place, and for inhabited systems installations will be constructed at the zenith and nadir points to facilitate this: transfer facilities, repair yards, and [[recharge station]]s.  These two locations simplify navigation so much that they were used in the early 2100s by the [[Deimos Project]] for test jumps before mankind made interstellar jumps, and have remained the standard jump points for travel by Kearny-Fuchida drive ever since - hence, they are called the "Standard Jump Points". They are also often referred to as "zenith" and "nadir" jump points because of their locations above (zenith) and below (nadir) the star, with respect to the layout of the star system.<ref name=BS44/><ref name=DJOM30/><ref name=AT57/>
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Standard jump points are also frequently where customs inspectors and defensive units are located, and as such travelers wishing to avoid such entanglements will attempt other points instead.
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== Pirate Points--Non-Standard Proximity Points ==
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The "life zone" around a star, where habitable planets tend to appear, is much closer to a star than its jump proximity limit, ranging from about 2 gigameters for red stars to up to 38 terameters for blues. <ref>'Campaign Operations'', p. 101</ref>  Difficulties and hazards notwithstanding, choosing to use a non-standard proximity point in or near a star system's planetary disk can reduce interplanetary travel times by about 5% to 10% (aassuming 1 G acceleration).  <ref>''DropShips and JumpShips - Operations Manual'', p. 17</ref><ref>''Campaign Operations'', p. 101</ref>
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== Pirate Points--Transient Points ==
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There are some jump points that will allow a JumpShip to enter a system inside the proximity limit. As these points are much closer to the habitable planets of a star system, they are prime choices for raiders and pirates, making them ideal "pirate points".  These jump points exist where the gravitational attraction of all planetary objects cancels each other out and overall gravitation is reduced below the critical limit for hyperspace field formation.<ref name=AT57/>
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While transient point locations can be estimated by secondary school physics (generally, transient points inside the proximity limit are close to L1 [[w:Lagrangian point|Lagrange Points]] <ref>''Strategic Operations: Advanced Aerospace Rules'', p. 74</ref> which exists due to the cancellation of gravity between two bodies), such jump points are difficult for JumpShips to utilize because they are much smaller than the standard jump points and have much more complicated motions. Rather than only following the star like the zenith and nadir points, the pirate points are subject to gravity of other moving objects in the star system.
  
Since JumpShips only carry [[DropShip|DropShips]] between stars, the DropShips are responsible for transporting cargo to and from a planet. The amount of time required for a trip from a planet to a JumpShip or the reverse depends on the distance the JumpShip must maintain from the star to remain in the gravity well. That distance is determined by the type of star and can range anywhere from 75 million kilometers (for a low-energy M9 star) to over 347 billion kilometers (for a high-energy B0 star).
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This makes a navigator's job nightmarish when attempting to use a transient point. Plotting the jump is impossible without computer aid, and can take hours with one. Missing the jump point is entirely possible, resulting in the JumpShip attempting to arrive in a region of space that is not a valid jump point (a fate discussed under [[Misjump]]).<ref name=BS44/><ref name=DJOM30/><ref name=AT57/>
  
The energy output from the star (also based upon its type) determines how long a JumpShip can recharge its drive and can range anywhere from 151 hours (for a B0 star type) to 210 hours (for an M9 star type). The actual time required between jumps must also include the [[Jump Sail]] deployment and recovery times, typically about 100 minutes for deployment and 150-200 minutes for recovery. If the Jump Sail is damaged or cannot be deployed, the JumpShip's power plant can be used to recharge the drive (called "quick charge"), but this may damage the drive and render the JumpShip inoperable.
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==References==
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<references />
  
== Pirate Jump Points ==
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==Bibliography==
There are some non-standard jump points that will allow a JumpShip to enter a system much closer to the destination planet than the star's zenith or nadir jump points will. They are commonly used in high-risk military operations where surprise is vital to the operation's success. Jumping into a pirate point poses several risks, which is why most traditional merchants and even military units will not use them. Because of potential solar system instability, it is possible that the JumpShip could appear too close to a system body, which could destroy the vessel and its passengers. Another issue is that the JumpShip must recharge its K-F drive using its engine rather than the Jump Sail. This could potentially damage the fragile drive and render the JumpShip inoperable.
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* ''[[AeroTech 2]]''
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* ''[[BattleSpace]]''
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* ''[[DropShips and JumpShips]]''
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* ''[[Strategic Operations]]''
  
== Recharge Stations ==
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[[Category:Inner Sphere Culture]]
Some systems (particularly [[Successor State]] or regional capitals) provide recharge stations at one or possibly both jump points. These stations are capable of beaming stored energy directly at a JumpShip's JumpSail and reduces the recharge time to 150 hours in most cases.
 

Latest revision as of 07:27, 23 October 2023

Jump Points refer to any point at which a JumpShip may initiate or resolve a "jump" through interstellar space. Traditionally, there are two jump points in a system - the zenith and the nadir of a star's gravity well (normally above and below the star's planetary system ecliptic). There exist other points, called "pirate points", which a JumpShip can use; these points are more difficult to calculate, increase the chance of a Misjump occuring, and increase the likelihood of being stranded alone in the event of a misjump. However, in desperate situations or covert missions, the advantages of a speedy insertion can outweigh the inherent risks.

Because JumpShips are equipped only with weak station-keeping drives (capable of 0.1G of acceleration at most), travel between a jump point and a destination within a star system is left to other craft, primarily DropShips, which have the engines and fuel needed to make the multiday journey. The exception are combat JumpShips or WarShips which are capable of traveling under their own power.

Overview[edit]

A Kearny-Fuchida Drive must operate from some point in space where local gravity levels are below a certain minimum, allowing the K-F field to form properly. These points are generally referred to as "jump points". Finding valid jump points in both the origin and destination star systems requires calculations that take into account the positions large sources of gravitational influences, such as stars and planets.

Proximity Points[edit]

Within a star system, the biggest source of gravitational influence is the mass of star itself. For example, Sol itself accounts for over 99.8% of the mass of the entire Terran system. So almost all possible jump points are outside some minimum distance, the "proximity limit," from the system's star.[1][2][3] Jump points at the proximity limit, known as "proximity points," form a nearly uniform sphere that can range from about 75 gigameters for some red stars up to nearly 350 terameters for certain blue stars.[4]

Standard Jump Points[edit]

Calculating the location of proximity points is complicated by the motions of planets within the star system, each with their own gravitational influence. For example, proximity points in the Terran system exist near the orbital path of the gas giant Saturn, but using a proximity point near Saturn's path requires making sure that Saturn itself is not nearby.

From a computational standpoint, the easiest proximity points to determine in the Terran system are those points that Saturn never passes near. As planets tend to stay within a flattened planetary disk, the easiest proximity points to calculate are those that are "above" and "below" that disk. These points are known as the "zenith" and "nadir" points, respectively, and are collectively known as "standard jump points."

Standard jump points are where most civilian interstellar traffic takes place, and for inhabited systems installations will be constructed at the zenith and nadir points to facilitate this: transfer facilities, repair yards, and recharge stations. These two locations simplify navigation so much that they were used in the early 2100s by the Deimos Project for test jumps before mankind made interstellar jumps, and have remained the standard jump points for travel by Kearny-Fuchida drive ever since - hence, they are called the "Standard Jump Points". They are also often referred to as "zenith" and "nadir" jump points because of their locations above (zenith) and below (nadir) the star, with respect to the layout of the star system.[1][2][3]

Standard jump points are also frequently where customs inspectors and defensive units are located, and as such travelers wishing to avoid such entanglements will attempt other points instead.

Pirate Points--Non-Standard Proximity Points[edit]

The "life zone" around a star, where habitable planets tend to appear, is much closer to a star than its jump proximity limit, ranging from about 2 gigameters for red stars to up to 38 terameters for blues. [5] Difficulties and hazards notwithstanding, choosing to use a non-standard proximity point in or near a star system's planetary disk can reduce interplanetary travel times by about 5% to 10% (aassuming 1 G acceleration). [6][7]

Pirate Points--Transient Points[edit]

There are some jump points that will allow a JumpShip to enter a system inside the proximity limit. As these points are much closer to the habitable planets of a star system, they are prime choices for raiders and pirates, making them ideal "pirate points". These jump points exist where the gravitational attraction of all planetary objects cancels each other out and overall gravitation is reduced below the critical limit for hyperspace field formation.[3]

While transient point locations can be estimated by secondary school physics (generally, transient points inside the proximity limit are close to L1 Lagrange Points [8] which exists due to the cancellation of gravity between two bodies), such jump points are difficult for JumpShips to utilize because they are much smaller than the standard jump points and have much more complicated motions. Rather than only following the star like the zenith and nadir points, the pirate points are subject to gravity of other moving objects in the star system.

This makes a navigator's job nightmarish when attempting to use a transient point. Plotting the jump is impossible without computer aid, and can take hours with one. Missing the jump point is entirely possible, resulting in the JumpShip attempting to arrive in a region of space that is not a valid jump point (a fate discussed under Misjump).[1][2][3]

References[edit]

  1. 1.0 1.1 1.2 BattleSpace - Rulebook, pp. 42, 44
  2. 2.0 2.1 2.2 DropShips and JumpShips - Operations Manual, pp. 28–30
  3. 3.0 3.1 3.2 3.3 AeroTech 2, pp. 56–57
  4. Campaign Operations, p. 100
  5. 'Campaign Operations, p. 101
  6. DropShips and JumpShips - Operations Manual, p. 17
  7. Campaign Operations, p. 101
  8. Strategic Operations: Advanced Aerospace Rules, p. 74

Bibliography[edit]