NASA’s two rovers Spirit and Opportunity discovered abundant evidence that water once flowed on Mars. Both rover ended their missions by falling silent within dunes but the mission continues via orbiter and lander probes.
Last February, NASA’s Perseverance rover arrived in Jezero Crater and began caching samples for later retrieval. Meanwhile, other missions, including one with a Chinese orbiter-lander-rover set for Mars, are on their way.
Spacecraft Design
Humanity’s success beyond low Earth orbit will require a space station and spacecraft capable of reaching it, equipped with living quarters, research labs, communication links with Earth and other spacecraft and sustainable food, water and oxygen supplies as well as mining facilities that tap into Earth’s resources for propellant purposes.
Spacecraft structures must be resilient enough to withstand random excitations and sinusoidal vibrations that occur during liftoff and transonic flight, typically by employing graphite-epoxy composite material with customizable strength, rigidity and thermal expansion properties that can be controlled through selecting appropriate orientations and contents of graphite fibers embedded within an epoxy matrix matrix.
One of the key components will be the Integrated Power and Attitude Control System (IPACS), which utilizes flywheels to store energy while also providing thrust for spacecraft maneuvering. A key aspect of this technology is a control algorithm which alternates spinning up and spinning down of flywheels, thus eliminating control surfaces on spacecraft.
Orbital Flight
Space travel requires orbital mechanics – an offshoot of celestial mechanics that applies mathematical analysis and engineering principles – in order to achieve success. This field determines a spacecraft’s trajectory towards its intended orbital destination.
To reach its desired orbit, a spacecraft must be launched with great velocity. To be effective, its launch should occur as fast as possible depending on its mass and desired altitude – the higher they go up, the faster the rocket must travel.
At such speed, rockets require considerable amounts of energy – hence why many rockets are only suitable for single use. Jeff Bezos’ Blue Origin has announced plans to make their rocket boosters reusable.
An orbit for any spacecraft is generally an ellipse with Earth as one of two foci. If a spacecraft has thrust available, they can make this more circular by decreasing velocity at perigee and increasing it at apogee – something Apollo astronauts did to place their craft in lunar orbit around its gravitational field.
Getting There
Astronomers need to do plenty of calculations and estimations when planning missions to Mars. Their orbit positions must line up correctly for maximum fuel efficiency during their trip.
Spacecraft must also be protected against harmful solar radiation, so scientists plan their flight for when its activity has decreased significantly – known as solar minima.
Reaching Mars takes an enormously long time, but engineers are working on solutions to make travel faster. One such way could be using laser propulsion system which would shorten travel time to less than nine months.
Once on Mars, the spacecraft will conduct extensive investigations of its atmosphere and weather using an array of instruments. With cameras equipped for image capture, dust storms, clouds, water vapor and other atmospheric phenomena can be observed with ease; also samples from soil and rocks will allow it to learn more about Mars before returning with up to 54,000 km/h velocity back home at mission completion.
Landing
Space engineers dedicate much of their efforts to understanding how best to land on Mars. This involves selecting an optimal landing site and carefully planning when to arrive on its surface.
As soon as it unhooks from its rocket, the spacecraft enters an extremely thin atmosphere surrounding Mars which acts to slow it down and ease into gentle landing on its surface.
Once close to Mars, the vehicle deploys a parachute and airbags that help it smash through the atmosphere at about 13,000 km/h before firing solid rockets that connect it to a “sky crane,” lowering it onto its final target.
Once on the surface, the rover uses its chemistry set to inspect rocks and search for signs of past life. Mars may seem tantalizingly close; but reaching it requires perseverance; only half of missions make it to this distant planet successfully – meaning sending even an automated vehicle there requires great creativity and perseverance – let alone human visitors!