Method for deploying multiple spacecraft

• US 7,219,858 B2
• Filed: 07/06/2004
• Issued: 05/22/2007
• Est. Priority Date: 07/06/2004
• Status: Expired due to Fees

• Current Assignee: Johns Hopkins University
• Original Assignee: Johns Hopkins University
• Inventors: Sharer, Peter J.
• Primary Examiner(s): Clement; Michelle
• Assistant Examiner(s): Lee; Benjamin P.
• Application Number:
  US10/884,901
• Publication Number:
  US 20060016934A1
• Time in Patent Office: 1,050 Days
• Field of Search: 244/158.4, 244/158.5, 244/158.6, 244/158.7, 244/158.8, 244/172.4, 244/172.5
• US Class Current: 244/158.4
• CPC Class Codes: B64G 1/1085 Swarms and constellations
• CPC Class Codes: B64G 1/242 Orbits and trajectories
• CPC Class Codes: B64G 1/2427 Transfer orbits
• CPC Class Codes: B64G 1/34 using gravity gradient

Abstract

A method for deploying multiple spacecraft is disclosed. The method can be used in a situation where a first celestial body is being orbited by a second celestial body. The spacecraft are loaded onto a single spaceship that contains the multiple spacecraft and the spacecraft is launched from the second celestial body towards a third celestial body. The spacecraft are separated from each other while in route to the third celestial body. Each of the spacecraft is then subjected to the gravitational field of the third celestial body and each of the spacecraft assumes a different, independent orbit about the first celestial body. In those situations where the spacecraft are launched from Earth, the Sun can act as the first celestial body, the Earth can act as the second celestial body and the Moon can act as the third celestial body.

Claims

1. A method for deploying a plurality of spacecraft about a first celestial body comprising the steps of:

(a) storing a first spacecraft and a second spacecraft aboard a spaceship;

(b) launching, at a launch time within a launch window, the spaceship from a second celestial body that orbits the first celestial body;

(c) flying the spaceship towards a third celestial body that orbits the second celestial body;

(d) separating the first spacecraft and the second spacecraft from the spaceship while the spaceship is traveling towards the third celestial body;

(e) separating the first spacecraft from the second spacecraft while the spaceship is traveling towards the third celestial body;

(f) establishing a first trajectory for the first spacecraft leading to a first spacecraft flyby past the third celestial body, the first trajectory including multiple orbits about the second celestial body during which orbit period corrections are made to account for the time of launch in step (b), such that after the multiple orbits the first spacecraft flyby will coincide with a predetermined first-second-third celestial body orbital geometry regardless of the launch time within the launch window;

(g) establishing a second trajectory for the second spacecraft leading to a second spacecraft flyby past the third celestial body, the second trajectory including multiple orbits about the second celestial body during which orbit period corrections are made to account for the time of launch in step (b), such that after the multiple orbits of the second trajectory the second spacecraft flyby will coincide with the predetermined first-second-third celestial body orbital geometry regardless of the launch time within the launch window, wherein the first trajectory is different than the second trajectory;

(h) performing the first spacecraft flyby, including subjecting the first spacecraft to a gravitational force of the third celestial body whereby the first trajectory of the first spacecraft is modified and the first spacecraft assumes a first orbit about the first celestial body;

(i) performing the second spacecraft flyby, including subjecting the second spacecraft to the gravitational force of the third celestial body whereby the second trajectory of the second spacecraft is modified and the second spacecraft assumes a second orbit about the first celestial body; and

wherein the first orbit is different from the second orbit and the first and second spacecraft are positioned on opposite sides of the second body.

2. The method according to claim 1, further comprising the step of subjecting the second spacecraft to the gravitational field of the third celestial body a second time.

3. The method of claim 2, wherein steps (g) and (i) cause the second spacecraft to traverse an orbit outer-loop segment that is outside an orbit of the third celestial body around the second celestial body in preparation for subjecting the second spacecraft to the gravitational field of the third celestial body a second time.

4. The method according to claim 1, wherein the first orbit is circumferentially ahead of an orbit of the second celestial body.

5. The method according to claim 1, wherein the second orbit is circumferentially behind an orbit of the second celestial body.

6. The method according to claim 1, wherein an N number of spacecraft are stored aboard the spaceship.

7. The method according to claim 1, wherein the first orbit is smaller than an orbit of the second celestial body.

8. The method according to claim 1, wherein the second orbit is larger than an orbit of the second celestial body.

9. The method according to claim 1, wherein an angular displacement of the first spacecraft from the second celestial body is approximately equal to an angular displacement of the second spacecraft from the second celestial body.

10. The method of claim 1, wherein:

step (f) comprises maneuvering the first spacecraft at perigee and apogee positions of the multiple orbits of the first spacecraft to make the orbit period corrections thereof; and

step (g) comprises maneuvering the second spacecraft at perigee and apogee positions of the multiple orbits of the second spacecraft to make the orbit period corrections thereof.

11. The method of claim 1, wherein steps (f), (g), (h) and (i) together cause an eccentricity of the first and second orbits about the first celestial body to be minimized.

12. The method of claim 1, wherein the first celestial body is the sun, the second celestial body is the earth, and the third celestial body is the moon.