1 / 5

Task 1 – Deep Impact

Task 1 – Deep Impact. So far the only impact demonstration was done by the Deep Impact mission. A 350 kg projectile hit the comet with 10.2 km/s. The comet has a size of about 8 x 5 x 5 km 3 . What are reasonable assumptions for the momentum transfer coefficient b ?

izzy
Télécharger la présentation

Task 1 – Deep Impact

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Task 1 – Deep Impact • So far the only impact demonstration was done by the Deep Impact mission. A 350 kg projectile hit the comet with 10.2 km/s. The comet has a size of about 8 x 5 x 5 km3. • What are reasonable assumptions for the momentum transfer coefficient b? • What is the velocity change (assume a reasonable b)? • Assume the comet is hit in apocenter– how much later does it arrive atpericenter compared to without hit?What distance does that correspondto? • a = 3.12404524 AU • e = 0.516946

  2. Task 1 – Deep Impact • Reminder: • From Kepler 1 • Kepler 3 • Vis-Viva • Gravitational constant: 6.67300.10-11 m3kg-1s-2 • Mass of the Sun: 1.98892.1030 kg •  = GM

  3. Task 2 - Apophis flyby • Apophis will have a close encounter on 13 Apr 2029, flyby distance is 0.0002547 AU. • (a) What is the expected brightest magnitude of the object? (Albedo = 0.33, diameter 0.27 km) • (b) What will be the relative flyby velocity? (a = 0.922296 AU, e = 0.19109) • (c) How long will it roughly take to cross half the sky (90 deg)? And the diameter of the Moon (0.5 deg)? • (d) If it did hit – what’s the released energy in comparison to the Hiroshima bomb? • Impact energies are often given in ‘kilotons TNT’ or ‘megatons TNT’ • 1 kt TNT = 4.184 * 1012 J • The ‘little boy’ Hiroshima bomb had an explosive yield of 15 kt TNT

  4. Task 2 – Apophis flyby – p. 2 • Reminder for (a): MSun = -26.7

  5. Task 3 – Apophis deflection • Rosetta (~2 t) was sent away from the Earth with 3.5 km/s – let’s assume we use it to deflect Apophis, when Apophis is at r = 1 AU. Assume b = 2 and 20 % loss because of different velocity vector directions. • Approximation: ds = 3 * dv * t (Chesley 2005)

More Related