Spirit and Opportunity Rovers

NASA’s Mars Exploration Rover Mission (MER), is an ongoing robotic space mission involving two rovers, Spirit and Opportunity, exploring the planet Mars. It began in 2003 with the sending of the two rovers — MER-A Spirit and MER-B Opportunity — to explore the Martian surface and geology. The Mars Rover Spirit landed on the Martian surface on the 4th January 2004 and Opportunity on the 25th January 2004, since then the rovers have continually send back data about the red planet.

Each rover is made up of a panoramic camera at human-eye height, and a miniature thermal emission spectrometer, with infrared vision, which help scientists identify the most interesting rocks. The rovers can watch for hazards in their way and manoeuvre around them. Each six-wheeled robot has a deck of solar panels, about the size of a kitchen table, for power. The rover drives to the selected rock and extends an arm with tools on the end. Then, a microscopic imager, like a geologist’s hand lens, gives a close-up view of the rock’s texture. Two spectrometers identify the composition of the rock. The fourth tool substitutes for a geologist’s hammer. It exposes the fresh interior of a rock by scraping away the weathered surface layer

The Mars Exploration Rover mission seeks to determine the history of climate and water at sites on Mars where conditions may once have been favourable to life. Each rover is equipped with a suite of science instruments that will be used to read the geologic record at each site, to investigate what role water played there, and to determine how suitable the conditions would have been for life.

Mars Exploration Rover Mission: Quick Facts

The following lists a few key facts of the equipment used to deliver the Rovers, Spirit and Opportunity, to the surface of Mars.

Spacecraft

Cruise vehicle dimensions: 2.65 meters (8.7 feet) diameter, 1.6 meters (5.2 feet) tall
Rover dimensions: 1.5 meter (4.9 feet) high by 2.3 meters (7.5 feet) wide by 1.6 meter (5.2 feet) long
Weight: 1,062 kilograms (2,341 pounds) total at launch, consisting of 174-kilogram (384- pound) rover, 365-kilogram (805-pound) lander, 198-kilogram (436-pound) backshell and parachute, 90-kilogram (198-pound) heat shield and 183-kilogram (403-pound) cruise stage, plus 52 kilograms (115 pounds) of propellant
Power: Solar panel and lithium-ion battery system providing 140 watts on Mars surface/li>
Science instruments: Panoramic cameras, miniature thermal emission spectrometer, Mössbauer spectrometer, alpha particle X-ray

spectrometer, microscopic imager, rock abrasion tool, magnet arrays

Rover A Mission (Spirit)

Launch vehicle: Delta II 7925
Launch period: June 8-24, 2003
Earth-Mars distance at launch: 105 million kilometers (65 million miles)
Mars landing: Jan. 4, 2004, at about 2 p.m. local Mars time (8:11 p.m. Jan. 3 PST)
Landing site: Gusev Crater, possible former lake in giant impact crater
Earth-Mars distance on landing day: 170.2 million kilometers (105.7 million miles)
One-way speed-of-light time Mars-to-Earth on landing day: 9.46 minutes
Total distance traveled Earth to Mars (approximate): 500 million kilometers (311 million miles)
Near-surface atmospheric temperature at landing site: -100 C (-148 F) to 0 C (32 F)
Primary mission: 90 Mars days, or “sols” (equivalent to 92 Earth days)

Rover B Mission (Opportunity)

Launch vehicle: Delta II 7925H (larger solid-fuel boosters than 7925)
Launch period: June 25-July 15, 2003
Earth-Mars distance at launch: 89 million kilometers (55 million miles)
Mars landing: Jan. 25, 2004, at about 1:15 p.m. local Mars time (8:56 p.m. Jan. 24 PST)
Landing site: Meridiani Planum, where mineral deposits suggest wet past
Landing time: Approximately 1:15 p.m. local Mars time (8:56 p.m. PST)
Earth-Mars distance on landing day: 198.7 million kilometers (123.5 million miles)
One-way speed-of-light time Mars-to-Earth on landing day: 11 minutes
Total distance traveled Earth to Mars (approximate): 491 million kilometers (305 million miles)
Near-surface atmospheric temperature at landing site: -100 C (-148 F) to 0 C (32 F)
Primary mission: 90 Mars days, or “sols” (equivalent to 92 Earth days)

Program

Cost: Approximately $800 million total, consisting approximately of $625 million spacecraft development and science instruments; $100 million launch; $75 million mission operations and science processing