Science - Mariner 10. I'm just bad at researching!?

Question

Can anyone PLEASE find out "why Mariner 10 (space probe) instead of going straight to Mercury went around the sun and past Venus? (or something like that) PLEASE?? I need it!

Answer 1

Mariner 10 was the seventh successful launch in the Mariner spacecraft series, and the first to use the gravitational pull of one planet (Venus) to reach another (Mercury). Instruments on board the spacecraft were designed to measure the atmospheric, surface, and physical characteristics of Mercury and Venus. Experiments included television photography, magnetic field, plasma, infrared radiometry, ultraviolet spectroscopy, and radio science detectors. An experimental X-band, high-frequency transmitter was flown for the first time on the spacecraft.

On November 3, 1973, Mariner 10 was placed in a parking orbit after launch for approximately 25 minutes, then placed in orbit around the Sun en route to Venus. The orbit direction around the Sun was opposite to that of the Earth. Mariner 10 flew past Venus on February 5, 1974, at a distance of 4,200 kilometers (2,610 miles). More than 4,000 photos of Venus revealed a nearly round planet enveloped in smooth cloud layers. Venus exhibited a slow rotational period of 243 days and had only 0.05 percent of Earth's magnetic field. The planet's atmosphere was composed mostly of carbon dioxide.

After the Venus flyby, Mariner's trajectory was bent in toward the Sun to accelerate and fling it out of Venus's gravitational field and onward to Mercury. Mariner 10 reached Mercury on March 29, 1974, passing over the planet at 705 kilometers (438 miles) above the surface. A second encounter with Mercury occurred on September 21, 1974, at an altitude of about 47,000 kilometers (29,200 miles). The sunlit side of the planet and the south polar region were photographed. A third and last Mercury encounter, at an altitude of 327 kilometers (203 miles), occurred on March 16, 1975. About 300 additional photographs were obtained along with magnetic field measurements. Photographs of the planet reveal an intensely cratered, Moon-like surface and a faint atmosphere of mostly helium, resulting from solar wind bombardment. Engineering tests were continued until March 24, 1975, when the supply of attitude-control gas was depleted and the mission was terminated.

Answer 2

It saves a lot of fuel using one planet to adjust your trajectory when you're flying to another one. And it also gave them a chance to get a good look at Venus.

Answer 3

Hi. This may help : http://www.answers.com/main/ntquery?s=Mariner%2010&gwp=16