Kepler

Launch data: Designation  34380 / 09011A Launch date  07 Mar 2009 - 03:50 UT  (10:49 pm. EST) Launch site  CC, SLC-17B Launch vehicle  Delta-7925-10L Mission   Astronomy Heliocentric orbit Perihelion / Aphelion   A.U. Eccentricity   Inclination   deg Period   min

Spacecraft data: Prime contractor   Operator  NASA JPL Platform  Bell Aerospace Mass at launch  1039 kg Dry Mass   kg Basic shape  cylindrical with solar panels Dimensions (m)   Solar array   Stabilization   DC power   Design lifetime  4 yrs - in Solar orbit

Decay:

Descriptions:

• Kepler is an astrometry science mission, launched for NASA JPL and using a Bell Aerospace platform. The body of the satellite is cylindrical with solar panels attached. It carries a 0.95 metres aperture differential photometer and the intention is to use the satellite to observer the structure and diversity of extra-solar planetary systems. Satellite has been placed into an Earth-trailing heliocentric orbit.
• Kepler is a spaceborne telescope designed to search the nearby region of our galaxy for Earth-size planets orbiting in the habitable zone of stars like our sun. The habitable zone is the region around a star where temperatures permit water to be liquid on a planet's surface. The challenge for Kepler is to look at a large number of stars in order to statistically estimate the total number of Earth-size planets orbiting sun-like stars in the habitable zone. Kepler will survey more than 100,000 stars in our galaxy.
• System Characteristics:
  • Spacebased Photometer: 0.95-m aperture
  • Primary mirror: 1.4 meter diameter, 85% light weighted
  • Detectors: 95 mega pixels (21 modules each with two 2200x1024 pixel CCDs)
  • Bandpass: 430-890 nm FWHM
  • Dynamic range: 9th to 16th magnitude stars
  • Fine guidance sensors: 4 CCDs located on science focal plane
  • Attitude stability: < 9 milli-arcsec, 3 sigma over 15 minutes.
  • Avionics: Fully block redundant
  • Science data storage: >60 days
  • Uplink X-band: 7.8125 bps to 2 kbps
  • Downlink X-band: 10 bps to 16 kbps
  • Downlink Ka-band: Up to 4.33125 Mbps
  • Photometric One-Sigma Noise Designed Performance:
  • Total noise with solar-like stellar variability and photon shot noise for an mv=12 star: < 2x10-5
  • No mechanisms other than a one-time ejectable cover and three focus mechanism for the primary mirror.
  • Flight segment and instrument mass: 1071 kg, maximum expected (10/06)
  • Flight segment and instrument power: 771 W, maximum expected (10/06)

Mission details:

• The Kepler space telescope was launched on Mar 7, 2009 into a hyperbolic Earth escape trajectory. Kepler is a Schmidt-type telescope with a 1.4-meter primary mirror, and will stare at one field in Cygnus, between Deneb and Vega, monitoring stars to search for transiting planets.
• The Delta 7925-10L rocket put Kepler in a 185 x 185 km x 28.5 deg parking orbit at 03:59 UTC; at 04:43 second stage restart put it in a 174 x 2815 km x 28.5 deg intermediate orbit, quickly followed at 04:45 by third stage burn to escape trajectory. The second stage depletion burn then put the empty stage in a 2246 x 7360 km x 28.55 deg disposal orbit.
• Kepler will leave the Earth-Moon system quite slowly on a 185 x -1372000 km x 28.5 deg hyperbola, passing lunar orbit at 04:20 UTC on Mar 9, and leaving the sphere of influence at 21:30 UTC on Mar 13.
• At 02:18 UTC on Apr 8, 2009 Kepler ejected its 7.5 kg dust cover; the telescope is now open to space. The dust cover will orbit the Sun in a fractionally different path thanks to its 1.1 m/s ejection velocity, its orbital period different by less than an hour. Kepler was 3.1 million km from Earth at the time of ejection, in a 0.97 x 1.04 AU orbit inclined 0.46 deg to the ecliptic plane, at ecliptic latitude 0.3 deg and ecliptic longitude 197.3 deg. Light travel time to Earth was 10 seconds.
• By Apr 20, 2009 range will be 4.5 million km and Kepler will be in a 0.967 x 1.041 AU x 0.5 deg heliocentric ecliptic orbit.
• In 2012, NASA′s orbiting Kepler telescope has discovered an unlikely pair of planets orbiting a distant star. One is small and rocky, the other is large and gaseous. What makes them unusual is that both are orbiting close to their parent star and they routinely come very close to each other, within only 1.2 million miles.
• The new planetary pair was identified circling a star called Kepler-36, which is about 1,200 light-years from Earth in the constellation Cygnus. The star was already known to have one planet circling it.
• 2015: K2-18b was identified as part of the Kepler space telescope program, one of over 1,200 exoplanets discovered during the "Second Light" K2 mission. The discovery of K2-18b was made in 2015, orbiting a red dwarf star (now known as K2-18) with a stellar spectral type of M2.8 about 124 light-years (38 pc) from Earth. The planet was detected through variations in the star′s light curve caused by the transit of the planet in front of the star as seen from Earth.
• On Oct 30, 2018 NASA announced that the Kepler space telescope, out of propellant, is being retired. Kepler was launched in 2009 and has revolutionized our knowledge of exoplanets, showing that Earth-sized objects orbit most of the stars in the sky. Kepler is in an Earth-trailing solar orbit, currently about 68 degrees behind us in the vicinity of Earth-Sun L5.

External links:

• NASA Ames Research Center: Kepler Planet discoveries.
• Los Angeles Times: Kepler Planet discoveries.
• Wikipedia: Kepler-36b.
• Wikipedia: Kepler K2-18b.
• Satellite tracking (n2ya.com): Real time satellite tracking