Grand Slam Passive Seismometer

Grand Slam Passive Seismometer
Environmental sensor by Probodobodyne Inc
Cost	(total)	4 000.00
Mass	(total)	0.035 t
Drag		0.1
Max. Temp.		1200 K
Impact Tolerance		5 m/s
Research		Electronics
Unlock cost		12 000
Since version		1.7.1
Part configuration		seismicSensor.cfg
Experiment		Surface Deployed Seismic Sensor
Packed volume		25 l
Power required		1 unit

Product description

“

This ground-deployed sensor contains very delicate, sophisticated accelerometers meant to detect and analyze the precisely calibrated seismic shock waves generated by smashing rocket parts at high speed into whatever planet or moon it happens to be sitting on. Note: Please allow trained Scientists to deploy for best results. Needs a deployed power unit & central station to operate. — Probodobodyne Inc

”

Usage

This is the only deployable science module which doesn't send science points through time. Instead, it works by impacting objects near the seismometer.

Science value calculation

The fraction of the Seismic Sensor's amount of science that is achieved by an impact is computed as Sensor Readings · Distance Attenuation · Setup.

(The seismometer's context menu entry "Science Completed" shows the sum of this value for all impacts it recorded.)

The amount of science points generated by an impact is the above fraction times the experiment's total value (80 Points) times the celestial body surface science multiplier.

For example, an impact with a sensor reading of 40%, an attenuation value of 65% and a setup value of 80% achieves a fraction of 0.4 · 0.65 · 0.8 = 0.208 i.e. 20.8% of the Seismic Sensor's total experiment value. (It would take 5 such impacts to generate the full amount of science that the Seismic Sensor can generate.) If this impact were to happen on Moho (whose surface science multiplicator is 10), the amount of science generated by the impact would be 0.208 · 80 · 10 = 166.4 science points.

Sensor Readings

The "Sensors Readings" value is the kinetic energy of the impactor divided by an energy value specific to the celestial body. The kinetic energy is calculated as follows: ${\text{Energy}}=0.5\times {\text{Mass}}\times {\text{Speed}}^{2}$ where the mass is in kg, the speed in m/s, and the energy in Joule.

The table for the celestial body values is as follows:

Body	Value
Moho	2.02e9J
Eve	9.78e10J
Gilly	1e6J
Kerbin	4.184e10J
Mun	7.82e8J
Minmus	2.12e7J
Duna	3.62e9J
Ike	2.23e8J
Dres	2.58e8J
Laythe	2.36e10J
Vall	2.49e9J
Tylo	3.39e10J
Bop	2.99e7J
Pol	8.66e6J
Eeloo	8.94e8J

For example a 4.5t impactor hitting at 1000m/s has an energy of 0.5 · 4500kg · 1000m/s ^ 2 = 2.25e9J . On Moho this gives a sensor reading of 2.25e9J / 2.02e9J = 1.11 i.e. 111%.

Distance Attenuation

The attenuation value depends on the distance of the impact point from the seismometer. It starts at 0% for a distance of zero meters, rises sharply to a maximum of 100% at a distance of 0.02 times the radius of the celestial body and then declines (slowlier) with further increasing distance. Erring towards a greater distance will result in a smaller decrease of the attenuation value than erring the same amount towards a smaller distance. For example on Moho with a radius of 250km the optimal distance is 0.02 · 250km = 5km, but a distance of 7km will also still result in an attenuation value of 100%.

Setup (Scientist bonus/malus)

The Setup value (which is shown as "Science Rate" in the seismometer's context menu) depends on the scientist level of the kerbal that deployed the seismometer, as given by this table:

Level	Value
Not scientist	0.05
Level 0	0.25
Level 1	0.35
Level 2	0.45
Level 3	0.60
Level 4	0.80
Level 5	1.00

This multiplier influences how much science is generated by each impact but not the total amount of science that the experiment can generate.

The total amount of science is as follows: base value of the module (80) · body surface science multiplier

Trivia

The Grand Slam Passive Seismometer is based on the Passive Seismic Experiment deployed by Apollo 12 to record lunar quakes and impacts such as meteorites or the discarded Lunar Module.

Changes

1.7.1

• Initial Release