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Realitat Ficció Feel free to leave the room if you are not prepared. A. Farrés (UB) Gravity: Science or Fiction SIMBa 2 / 23 Quick Synopsis of the Movie • It all starts with a “classical” operation mission at the Hubble Telescope (STS-157). • Then the crazy Russians make explode one of their satellites and create a cloud of debris. • This cloud of debris creates a reaction chain impacting on different satellites, telecommunication satellites may be off. Danger for the ISS and Hubble Telescope. • IMMEDIATE EVACUATION is required. • To late, the Hubble and all its passenger get hit by the debris. A. Farrés (UB) Gravity: Science or Fiction SIMBa 3 / 23 Quick Synopsis of the Movie • It all starts with a “classical” operation mission at the Hubble Telescope (STS-157). • Then the crazy Russians make explode one of their satellites and create a cloud of debris. • This cloud of debris creates a reaction chain impacting on different satellites, telecommunication satellites may be off. Danger for the ISS and Hubble Telescope. • IMMEDIATE EVACUATION is required. • To late, the Hubble and all its passenger get hit by the debris. The Adventure Begins !! A. Farrés (UB) Gravity: Science or Fiction SIMBa 3 / 23 The Hubble Telescope The Hubble telescope was launched in April 1997 and it has been working for more that 23 years. Orbital Parameters • Almost Circular Orbit (e ≈ 0) • Height: ≈ 559 km • Inclination: 28.5◦ • Orbital Period: 96 − 97 min (14 − 15 rev/day) • Orbital Velocity: ≈ 7.5 km/s. A. Farrés (UB) Gravity: Science or Fiction SIMBa 4 / 23 The Hubble Telescope There have been only 5 Serving Missions to the Hubble Telescope (SM1 December 1993, SM2 February 1997, SM3A December 1999, SM3B March 2002, SM4 May 2009) A. Farrés (UB) Gravity: Science or Fiction SIMBa 5 / 23 A. Farrés (UB) Gravity: Science or Fiction SIMBa 6 / 23 OMG (Oh My God!!) A. Farrés (UB) Gravity: Science or Fiction SIMBa 7 / 23 Space Population A. Farrés (UB) Gravity: Science or Fiction SIMBa 8 / 23 Space Population A. Farrés (UB) Gravity: Science or Fiction SIMBa 8 / 23 The Iridium 33/Cosmos 2251 Case Source: http://www.celestrak.com/events/collision/ A. Farrés (UB) Gravity: Science or Fiction SIMBa 9 / 23 The Iridium 33/Cosmos 2251 Case A. Farrés (UB) Gravity: Science or Fiction SIMBa 10 / 23 The Iridium 33/Cosmos 2251 Case A. Farrés (UB) Gravity: Science or Fiction SIMBa 11 / 23 Is a reaction chain possible ? • The Kessler syndrome (also called the Kessler effect, collisional cascading or ablation cascade), was proposed by the NASA scientist Donald J. Kessler in 1978. • It is a scenario in which the density of objects in Low Earth Orbit (LEO) is high enough that collisions between objects could cause a cascade, each collision generating space debris which increases the probability of further collisions. • One implication is that the distribution of debris in orbit could render space exploration, and even the use of satellites, unfeasible for many generations. [ Watch Video Iridium 33 and Cosmos 2251 Collision.mp4 ] [ Watch Video Dispersion.wmv ] A. Farrés (UB) Gravity: Science or Fiction SIMBa 12 / 23 A. Farrés (UB) Gravity: Science or Fiction SIMBa 13 / 23 A. Farrés (UB) Gravity: Science or Fiction SIMBa 14 / 23 A. Farrés (UB) Gravity: Science or Fiction SIMBa 14 / 23 A. Farrés (UB) Gravity: Science or Fiction SIMBa 14 / 23 Space Walks A. Farrés (UB) Gravity: Science or Fiction SIMBa 15 / 23 Plan to go Home Orbital Parameters • Almost Circular Orbit (e ≈ 0) Orbital Parameters • Almost Circular Orbit (e ≈ 0.00046) • Height: ≈ 559 km • Height: ≈ 417 km • Inclination: 28.5◦ • Inclination: 51.65◦ • Orbital Period: 96 − 97 min (14 − 15 rev/day) • Orbital Velocity: ≈ 7.5 km/s. A. Farrés (UB) • Orbital Period: 92.92 min (15.49 rev/day) • Orbital Velocity: ≈ 7.66 km/s. Gravity: Science or Fiction SIMBa 16 / 23 North pole Baikonur Cape Canaveral HST orbit: 28.5° inclination 559 km altitude Equator ISS orbit: 51.65° inclination 417-420 km altitude A. Farrés (UB) Gravity: Science or Fiction SIMBa 17 / 23 A. Farrés (UB) Gravity: Science or Fiction SIMBa 18 / 23 No Parachute = No Landing !! A. Farrés (UB) What can we do ? Gravity: Science or Fiction SIMBa 18 / 23 Lets go to Tiangong-1 Orbital Parameters Orbital Parameters • Almost Circular Orbit (e ≈ 0.00046) • Almost Circular Orbit (e ≈ 0.00055) • Height: ≈ 417 km • Height: ≈ 359.5 km • Inclination: 51.65 ◦ • Inclination: 42.78◦ • Orbital Period: 92.92 min (15.49 rev/day) • Orbital Period: 91.73 min (15.7 rev/day) • Orbital Velocity: ≈ 7.66 km/s. • Orbital Velocity: ≈ 7.5 km/s. A. Farrés (UB) Gravity: Science or Fiction SIMBa 19 / 23 A. Farrés (UB) Gravity: Science or Fiction SIMBa 20 / 23 Orbital Manoeuvres Summary of orbital Parameters: • Hubble: altitude ≈ 555km, orbital speed ≈ 7.70km/s, inclination 28.47◦ . • ISS: altitude ≈ 420km, orbital speed ≈ 7.66km/s, inclination 51.65◦ . • Tiangong: altitude ≈ 350km, orbital speed ≈ 7.58km/s, inclination 47.77◦ . • Change in Amplitude: • Hubble to ISS: ∆v ≈ 37.42m/s (each manoeuvre). • ISS to Tiangong: ∆v ≈ 19.87m/s (each manoeuvre). • Change in Inclination: • Hubble to ISS: ∆v ≈ 3.09km/s. • ISS to Tiangong: ∆v ≈ 0.52km/s. • MMU: ∆v ≈ 24.4m/s. • Soyuz: ∆v ≈ 250m/s (usually manoeuvres of max. 30m/s are done). Source: http://sattrackcam.blogspot.com.es/2013/10/a-space-buff-watches-gravity.html A. Farrés (UB) Gravity: Science or Fiction SIMBa 21 / 23 A. Farrés (UB) Gravity: Science or Fiction SIMBa 22 / 23 A. Farrés (UB) Gravity: Science or Fiction SIMBa 22 / 23 A. Farrés (UB) Gravity: Science or Fiction SIMBa 23 / 23