Space dataset

This dataset contains 1,698 observations of satelites between 1956 and 2013 where the study focuses failure and success once the satelite has reached its targeted orbit. Failures during the launching step or the testing step are not considered.

Usage

data(spacedata)

Format

spacedata is a data frame of 16 columns and 1,698 rows:

Event: A character string describing the launch: always "LAUNCH: Satellite launched successfully".
EventDate: The date of the launch.
MissionType: A character string describing the mission goals.
InitOrbit: A character string for the satelite orbit, see details.
OrbitRange: A character string summarizing the satelite orbit.
Position: A character for the position.
ContractLife: The contractual life (in years).
Sector: A character string: either "CIVIL" or "MILITARY".
IsCommercial: When civil usage, 1 indicates private (commercial), 0 public (institution).
Mass: Mass of satellite (Kg).
RetireDate: Date of retirement, if any.
TotalFailDate: Date of total failure, if any, see details.
PartialFailDate: Date of partial failure, if any, see details.
AnyFailDate: Date of first failure, in any.
OperLifeTime: Life Length of the satelite (in years) when operating successfully.
Censored: Indicator for censoring.

Details

The satelite orbit is an acronym given by

EO: Elliptical Orbit.
G: Geostationary.
GTO: Geostationary Transfert Orbit.
HEL: Heliocentric Orbit.
HEO: Highly Elliptical Orbit.
LEO: Low Earth Orbit.
MEO: Medium Earth Orbit.
PEO: Polar Elliptical Orbit.
PO: Polar Orbit.
SSO: Sun-Synchronous Orbit

Some details on earth orbit are given below:

LEO: Low Earth orbits (LEO) are defined to be orbits with an average altitude that is less than 2,000 km. An important subset of LEO is the sun-synchronous orbit (SSO). These are circular orbits with an altitude between 500 km and 1200 km that provide an orbital period that result in passes over a point on the Earth's surface at the same time of day, a fixed number of days apart. This is ideal for Earth observation missions. LEO has predominantly been used by civil and military agencies for Earth observation, scientific missions, manned missions and intelligence or spy satellites.
MEO: Medium Earth orbits (MEO) are defined to be orbits with an average altitude in the range of 5,000 to 20,000 km. The U.S. military were the first to exploit this orbit with the Global Positioning Satellites (GPS). The numerous satellites in the constellation appear to move slowly across the sky of an observer and several satellites are always visible at any point on the Earth's surface. A similar orbit is used by the Russia's equivalent Glonass system and the European Galileo.
GEO: The Geostationary Earth Orbit GEO type orbit features an altitude of approximately 36,000 km. The matched orbital period means that the satellite will appear to be nearly stationary in the sky of an observer, allowing for simplified earth communications and a global coverage. The main use of this type of orbit has been for the telecommunications industry, point-to-point, mobile and direct broadcast. A significant secondary user has been for Earth observation, especially meteorological but also military missile launch and nuclear explosion detection satellites. Commercial use of space satellites has tended to concentrate on the GEO orbit with the market predominantly developing in the late 1970s and throughout the 1980s and 1990s. Total demand for launches to GEO again increased to 1997, mainly due to commercial interests, before a sharp decline in demand into the early 2000s.

Generally, a difference is made between partial losses and total losses with the following definitions:

Total Loss - Constructive Total Loss:: (1) Total Loss means physical destruction of the spacecraft, no separation from the launch vehicle or injection in a useless orbit, loss of control of the spacecraft. (2) Constructive Total Loss means a partial loss where the loss ratio is equal or above 75 percent, assimilated to a Total Loss.
Partial Loss:: loss of performance impacting the spacecraft intended mission, reduction of useful lifetime, permanently intermittent mission based on a predetermined loss formula.

Source

Data based on two actuarial memoirs and partially modified to fit package standards.

References

Guelou, S. (2013). Risques spatiaux: modelisation de la fiabilite des satellites en orbite., EURo Institut d'Actuariat master thesis, University of Brest, France.

Gauche, J.F. (2012). Space risks., Centre d'Etudes Actuarielles master thesis, Paris, France.

Examples