As much as we all want to pretend to live in a world of science fiction, mankind is at least for the time being stuck here on Earth. Even so, humans know a fair bit more about our solar system than many argue we have any business knowing. This is all thanks to the fascinating spectacle of unmanned space probes.

The common focal point for most folks when they think of space probes is a fleet of rovers currently traversing the surface of Mars. In the past, Martian rovers have been tiny vehicles with a limited range and limited scientific abilities. In the year 2021 that, couldn't be further from the truth. NASA's current crop of Mars rovers, Curiosity, and Perseverance respectively make rovers of the past look like toys by comparison. You may be asking yourself how these tiny little spacecraft ballooned in size to be as large as the average economy car. Allow us to show you why.

Unlike your average car, Mars rovers aren't hauling groceries or planks of wood around. They carry the world's most advanced scientific instruments inside. Let's take an in-depth look at how Martian rovers grew to look more car-like, both in size and in capability. RELATED: Here's What These Space Shuttles Look Like From The Inside

Sending Lots Of Mass Into Deep Space Is Beyond Difficult

Ariane-5
Via: Airbus

The adage "It ain't rocket science" exists for a very good reason. Not only is sending anything man-made beyond the bounds of Earth technologically challenging, but also prohibitively expensive. According to NASA, it costs around $10,000 to send one pound of material just into low Earth orbit. That's not accounting for re-usable flight hardware like the space shuttle.

The costs of sending the same pound of material on a potential 100 million-plus mile voyage to the red planet are sure to send that number skyrocketing. With this in mind, it's easy to understand why all of the early attempts at unmanned Martian exploration were so small in stature.

Prop-M
Via: cyberneticzoo.com

The first man-made objects to touch down on the surface of Mars were Soviet probes under the "Mars" series of missions in the early 1970s. The Mars 3 mission carried the very first Martian rover; a tiny machine called the Prop-M. This tiny rover was just under ten pounds (4.5 Kg) in weight and had to be physically tethered to its lander mothership. This factor drastically limited in its scientific ability.

NASA-Sojourner-Rover
Via: NASA Jet Propulsion Laboratory

The first American Martien rover arrived on the surface on July 4th, 1997, as a part of the NASA-sanctioned Mars-Pathfinder mission. Named "Sojourner" after American abolitionist and women rights advocate Sojourner Truth, this rover was over twice as heavy as the Prop-M rovers at just over 25 pounds. It also carried far more scientific and analytic instruments on board. Military contractors McDonnell-Douglas, makers of the F-15 fighter jet, were contracted to construct the small, lightweight rover packed with the latest atmospheric analysis technology, as well as an advanced Alpha Particle X-Ray Spectrometer. A device that took accurate data regarding the chemical composition of the Martian soil by exposing soil samples to varying levels of X-Ray radiation. The Sojourner spent the eight-month voyage to Mars stowed away within the Pathfinder mothership all the way to the Martian surface. It touched the dunes of the red planet for the first time on the morning of July 5th, 1997. The rover took over 500 photographs and relayed invaluable data about the Martian atmosphere before losing contact with Earth 83 days after landing.

More Technology Means Bigger Wheels

Spirit-Rover-1
Via NASA Jet Propulsion Laboratory

In many ways, the twin rovers Spirit (MER-A) and Opportunity (MER-B) of the Mars Exploration Rovers program were the mechanical evolution of its predecessor Sojourner. Not only in appearance but in the scientific ability of its instruments. Weighing in at 400 pounds (180 Kg) and standing 4.9 feet (1.5 meters) with its mast fully extended, the twin rovers were similar in size to a large quad-bike or normal-sized golf cart. A large percentage (35 kilograms or 77 pounds) is taken by the six wheels and their suspension system.

Like Sojourner, the MER series of rovers were solar-powered. Unlike the fragile power supply on Sojourner, these solar pannels truly stood the test of time in the harsh Martian environment. A combined two decades' worth of dutiful service was performed by the two rovers performing scientific experiments on the Martian surface that advances mankind's search for extraterrestrial life. The last contact was made with the Spirit rover on March 22nd, 2011, and was declared inoperable in May of the following year. Opportunity soldiered on until the great Martian dust storm of 2018 brought the end of the MER program. RELATED: Virgin Galactic Is Sending This TikTok Star To Space

Curiosity And Perseverance: The Scientific Equivalent Of Fully Loaded

Curiosity-Rover
Via: NASA

In the summer of 2012. the red planet was introduced to planet Earth's latest advancements in autonomous rover technology. Weighing just over 2000 pounds (907 Kg), NASA's Curiosity rover weighed more than some subcompact cars here on earth, most notably beating out the CVT-equipped Mitsubishi Mirage by almost 200 pounds (90 Kg). Much of this weight is attributed to the radioisotope thermoelectric generator (RTG) power supply which uses radioactive isotopes to power a series of lithium-ion batteries. The Curiosity rover had the capabilities to do all the scientific research of its predecessors more effectively and faster while also bringing its own unique hardware on board. A fully telescopic arm can interact with the martian soil, take rock samples and even scan soil samples for fossilized signs of pre-historic life.

Persderverance-rover
Via: tekhdecoded.com

Curiosity was joined in May 2021 by its upgraded sister rover, Perseverance. At 2,300 pounds (1,043 Kg), the new rover weighs almost exactly as much as an ND Mazda MX-5. Both of these nuclear-powered rovers are expected to traverse the Martian surface for the better part of the next decade.

We've Come Quite A Long Way In Five Decades

Mars-Rovers
Via Nasa

If you despair that there hasn't been a man on the moon since the early 70s, it's important to remember that advances in spacelight are still being made. This time, the technology comes in the form of autonomous roving machines that allow us to explore the stars all from the comfort of Earth. Advancements in Martian rover technology is living proof of this. Sources: NASA NEXT: X-37B Spaceplane Wins Collier Trophy For Pushing Boundaries In Flight And Space