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Astrogation (skill)

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The Astrogation skill allows a character to make interstellar jumps. Characters trained in astrogation can make the complicated calculations required to take a starship on a safe course through the Void, and represents years of mathematical calculations and accurate estimations. As a result, this is not a common skill, and experienced Astrogators are in high-demand. Astrogators also have a chance to pinpoint their location in the galaxy if, for some reason, an interstellar jump deposits them somewhere other than their intended destination.

In the UPF Spacefleet, Astrogation is one of the three primary skills learned (at level 2) by graduate officers.

The qualifications needed to obtain a 1st level astrogation skill are: Computer 6.

Level EP Cost Daily Wage
1 8 +20
2 16 +40
3 36 +60
4 60 +80
5 80 +100
6 120 +120

Astrogators of all levels can perform all astrogation sub-skills.

Plot Interstellar JumpsEdit

(Success Rate: 100% on charted route with proper preparation)[1]

A ship that makes an interstellar jump must carry an astrogator, or the pilot will not be able to predict where the ship will exit the Void. The time needed to make course calculations increases for long jumps, because even small errors become very serious as the distance increases.

Normal plotting time for a jump is 10 hours for each light-year that will be jumped. For example, an astrogator plotting an 8 light-year jump must spend 80 hours performing calculations before the ship could accelerate to jump speed. This time must be spent actually making calculations; the referee should re member that astrogators need to sleep sometime. (If a player wants to work without sleeping, the referee can make a secret Stamina check - if the character fails, his calculations are wrong and the ship will drift off course.)

If a jump is made along one of the established travel routes marked on the Frontier Sector map, and the astrogator spends 10 hours per light-year making the proper course adjustments, there is no risk that the ship will leave the Void anywhere other than its planned destination.


It should be noted that plotting a jump targets not a system, but a planet within that system. Plotting a course to any other destination in the target system requires separate plotting. For example, Ship Alpha is orbiting Triad in the Cassidine system needs to go to Inner Reach, in the Dramune system; this is one route. Ship Beta, an identical ship with the same vector as Ship Alpha, needs to get to Outer Reach, in the same system. If both were heading to the same destination, they could link their navigation computers and the same set of coordinates would serve both ships, but since each has a different destination in the target system, each ship must plot its own course.

The course plotted includes the entire voyage, from boosting to void velocity, to the jump itself, to the turnaround and deceleration transit at the target system; properly calculated, at the end of its deceleration, the ship will be in orbit of its destination.

Risk JumpingEdit

(Success Rate: 10% x skill level + 10% per hour)

If for some reason an astrogator does not spend the full 10 hours plotting each light-year of an interstellar jump, there is a chance the ship will drift off course. Jumping without sufficient preparation is called Risk Jumping, or "smoking the jump."

The chance that a ship will reach its destination without sufficient course preparation depends on both the astrogator's skill level and the amount of time he spends planning the ship's course. To determine the exact percentage chance that the jump will be successful, follow the procedure below:

  1. Divide the total number of hours the astrogator spent preparing the course by the number of light-years in the jump. (Round down.)
  2. Add the astrogator's skill level to the result from step 1.
  3. Multiply the sum from step 2 by 10%. The result is the chance that the jump will be successful and the ship will arrive at the target system. The astrogator rolls d100, and if the result is equal to or less than the chance that the jump will succeed, then the ship arrives at its planned destination. Otherwise, the ship has exited the Void somewhere else.

Two restrictions apply to this process:

First, if the astrogator spends fewer than 10 hours plotting each light-year, a roll of 96-100 always means the ship misses its mark, even if the astrogator's modified chance to succeed is above 100.
Second, if the astrogator spends fewer than two hours planning each light-year, the ship will misjump automatically.

If the astrogator is using high-quality astrogation equipment (described in the Equipment section), he can add 5% to his chance to lay the course properly. This applies only to the most expensive equipment available.

EXAMPLE: Solleran is a 3rd level astrogator. His ship is carrying a desperately needed serum from Prenglar to the outpost at Dixon's Star. He wants to get the medicine there as soon as possible, so he spends only 25 hours plotting the 5 light-year course. The chance that Solleran's ship will actually arrive at Dixon's Star is (25/5 + 3) x 10, or 80%.

Find LocationEdit

(Success Rate: 30% + 10% x skill level)

When a ship misjumps, either because the astrogator spent too little time plotting the jump or because the ship was following an uncharted route, the ship will emerge somewhere other than its intended destination (see Misjumps in the Ship Movement section). The astrogator then must try to figure out where the ship is.

The astrogator can determine his position easily if the ship enters a colonized system, because all of the inhabited systems are charted in detail. The astrogator will recognize a charted system after only 1d10 hours of calculation.

A very simple way for a ship to find out whether a system is colonized is to broadcast a normal radio message. If anyone answers, the characters know there are intelligent creatures around. Unless the ship is very near a planet, however, the radio message may take several hours to reach a possible colony, and the reply will take just as long to return. Of course, any intelligent creatures who answer the message will also know that the characters are in system . . .

If the system is uncharted, the stars will appear in unfamiliar patterns and will be difficult to recognize. Unless the astrogator can determine the ship's position, the crew may never see home again. Determining the ship's position in an uncharted system takes 2d10 x 10 hours of calculations. The referee rolls d100. If the result is equal to or less than the astrogator's success rate for this subskill, the astrogator will know exactly where the ship is when he finishes his calculations. Like course calculations, these 2d10 x 10 hours do not include time for sleep.

If the astrogator does not pass the skill check, the referee must consider how close the roll was. If the roll was reasonably close, the astrogator will realize that he cannot locate the ship. If the roll was very much higher than the astrogator's success rate (at least 30 or 40 points higher), the referee may decide to tell the astrogator where the ship is, but deliberately give him false information If the astrogator cannot fix the starship's position, the ship can jump to another star and try again. The referee should simply move the ship to another randomly chosen star, because it will misjump automatically. The astrogator has a -10% penalty on his location roll at the new system and, if the ship must jump blind again, an additional -10% for each new system it enters. (By making blind jumps, the ship's position becomes more and more confused.) The referee should feel free to expand the Frontier map if a ship jumps off the edge. An astrogator using high-quality equipment gets an additional +5% bonus when trying to fix the ship's position.

If a ship misjumps to a star system that has never been explored, the route to that system is not considered charted or explored. Even if the astrogator locates the ship's position, he must also successfully chart a new route out of the system in order to leave safely.

Chart New RoutesEdit

(Success Rate: 50% +10% x skill level -5% x lightyears)

An astrogator has a chance to chart a new route to a system. New routes may be shortcuts between inhabited systems that are not directly connected (Prenglar and White Light, for example), or they may be routes to unexplored star systems. If an astrogator guides a ship successfully on an uncharted route, that astrogator can regard that route as charted if he ever travels it again. However, the route is charted in only one direction. To completely chart the route, the astrogator must guide the ship back to its starting point along the same path.

If the astrogator fails this subskill check, the ship misjumps (see Misjumping in the Ship Movement section).

Astrogators do not get a bonus for using high quality navigation equipment when trying to chart a new route.

If the astrogator chooses to tell the UPF about the route, the information will be fed into the Federation's computer banks and within a week the route will be considered as marked on the UPF astrogation charts.

The UPF pays a standard bonus of 100,000 Cr for information on new travel routes. By custom, this money is divided equally among the crew of the ship, as they all shared the risks of the jump. The Interstellar Distance Table. When an astrogator tries to chart a new route to a star, players need to know the distance between the origin and destination stars.


  1. See also: Buying plotted jumps from third parties

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