Overview

Perhaps the single largest expense in landing a rover on the moon is getting it there. The SpaceX corporation’s partnership with the Google Lunar XPrize makes working with them an ideal choice.

The Two Cups and a String rover will take advantage of the SpaceX Falcon1e. This rocket is perfectly suited to getting a rover the size of the TCS solution into orbit.

Within ten minutes of launch, the Falcon will break away and the TCS lander will be on its own. The thrusters will fire and the lander will begin its journey to the moon.

The trip from orbiting around the Earth to the moon’s surface will take approximately 5 days. The lander makes use of the Hohmann transfer from low Earth orbit to get to the moon. Our lander will need about 445 kg of fuel in order to make it to the moon’s surface safely [1]. Table 1, below, shows the fuel estimates, per stage of flight.

mf [kg]

mo [kg]

Ve [km/s]

deltaV [km/s]

LEO-Moon Orbit

60.7

494.9

2.83

-5.93

Trajectory Correction

494.9

503.2

2.83

-0.047

Cruise Attitude Control

503.2

505.2

2.83

-0.011

Table 1. Fuel calculations for the TCS lander’s orbit.

Once the lander has reached orbit around the moon, it must land. We have selected the site of the Apollo 15’s landing, as it is the closest landing site to the lunar equator, which is an added benefit.

The landing site of the Apollo 15, where the TCS lander will be coming down.

The TCS lander will be able to take pictures of the equipment left behind by Apollo 15, including the vehicle which the astronauts drove across the lunar surface.

The orbit mechanics system is typically one of the most expensive portions of any lunar mission, primarily because of the large expense involved in reaching space. The SpaceX corporation has provided a generous 10% discount to XPrize contestants, so including the cost of the launch with the cost of the fuel provides the total orbital costs shown below.

Cost

Launch (Falcon 1e)

$7.65 million

Fuel (N₂O₄ and MMH blend)

$36,000

Total Orbital Costs

$7.686 million

Note: The costs of much of the equipment, including the thrusters and fuel tanks, is included in the propulsion system ESTIMATES.