Image of the Martian atmosphere and surface obtained by the Viking 1 orbiter in June 1976. (Credit: NASA/Viking 1)
NASA is actively working to return surface samples from Mars in the next few years, which they hope will help us better understand whether ancient life once existed on the Red Planet’s surface billions of years ago. But what about atmospheric samples? Could these provide scientists with better information pertaining to the history of Mars? This is what a recent study presented at the 55th Lunar and Planetary Science Conference hopes to address as a team of international researchers investigated the significance of returning atmospheric samples from Mars and how these could teach us about the formation and evolution of the Red Planet.
NASA astronauts exploring Mars on future missions starting perhaps in the 2030’s will require protection from long term exposure to the cancer causing space radiation environment. Credit: NASA.
History was made on July 20th, 1969, when Apollo 11 astronauts Neil Armstrong and Buzz Aldrin set foot on the surface of the Moon. The moment was the culmination of decades of hard work, research, development and sacrifice. And since that time, human beings have been waiting and wondering when we might achieve the next great astronomical milestone.
So really, when will we see a man or woman set foot on Mars? The prospect has been talked about for decades, back when NASA and the Soviets were still planning on setting foot on the Moon. It is the next logical step, after all. And at present, several plans are in development that could be coming to fruition in just a few decades time.
Original Proposals:
Werner Von Braun, the (in)famous former Nazi rocket scientist – and the man who helped spearhead NASA’s Project Mercury – was actually the first to develop a concept for a crewed mission to Mars. Titled The Mars Project (1952), his proposal called for ten spacecraft (7 passenger, 3 cargo) that would transport a crew of 70 astronauts to Mars.
In between launching V-2s in New Mexico and developing rockets at Redstone Arsenal, Von Braun had time to write Mars Projekt (1952). Credit: Mars Project, Von Braun
His proposal was based in part on the large Antarctic expedition known as Operation Highjump (1946–1947), a US Navy program which took place a few years before he started penning his treatise. The plan called for the construction of the interplanetary spacecraft in around the Earth using a series of reusable space shuttles.
He also believed that, given the current pace of space exploration, such a mission could be mounted by 1965 (later revised to 1980) and would spend the next three years making the round trip mission. Once in Mars orbit, the crew would use telescopes to find a suitable site for their base camp near the equator.
A landing crew would then descend using a series of detachable winged aircraft (with ski landing struts) and glide down to land on the polar ice caps. A skeleton crew would remain with the ships in orbit as the surface crew would then travel 6,500 km overland using crawlers to the identified base camp site.
They would then build a landing strip which would allow the rest of the crew to descend from orbit in wheeled gliders. After spending a total of 443 days on Mars conducting surveys and research, the crew would use these same gliders as ascent craft to return to the mother ships.
Astronaut Eugene A. Cernan during the Apollo 17 mission, December 11th, 1972, shown conducting a checkout of the Lunar Roving Vehicle (LRV). Credit: NASA
Von Braun not only calculated the size and weight of each ship, but also how much fuel each would require for the round trip. He also computed the rocket burns necessary to perform the required maneuvers. Because of the detailed nature, calculations and planning in his proposal, The Mars Project remains one of the most influential books on human missions to the Red Planet.
Obviously, such a mission didn’t happen by 1965 (or 1980 for that matter). In fact, humans didn’t even return to the Moon after Eugene Cernan climbed out of the Apollo 17 capsule in 1972. With the winding down of the Space Race and the costs of sending astronauts to the Moon, plans to explore Mars were placed on the backburner until the last decade of the 20th century.
In 1990, a proposal called Mars Direct was developed by Robert Zubrin, founder of the Mars Society and fellow aerospace engineer David Baker. This plan envisioned a series of cost-effective mission to Mars using current technology, with the ultimate goal of colonization.
The initial missions would involve crews landing on the surface and leaving behind hab-structures, thus making subsequent missions easier to undertake. In time, the surface habs would give way to subsurface pressurized habitats built from locally-produced Martian brick. This would represent a first step in the development of in-situ resource utilization, and eventual human settlement.
Artist’s rendering Manned Habitat Units and Mars vehicles, part of the Mars Design Reference Mission 3.0. Credit: NASA
During and after this initial phase of habitat construction, hard-plastic radiation- and abrasion-resistant geodesic domes would be deployed to the surface for eventual habitation and crop growth. Local industries would begin to grow using indigenous resources, which would center around the manufacture of plastics, ceramics and glass out of Martian soil, sand and hydrocarbons.
While Zubrin acknowledged that Martian colonists would be partially Earth-dependent for centuries, he also stated that a Mars colony would also be able to create a viable economy. For one, Mars has large concentrations of precious metals that have not been subjected to millennia of human extracting. Second, the concentration of deuterium – a possible source for rocket fuel and nuclear fusion – is five times greater on Mars.
In 1993, NASA adopted a version of this plan for their “Mars Design Reference” mission, which went through five iterations between 1993 and 2009. And while it involved a great deal of thinking and planning, it failed to come up with any specific hardware or projects.
Current Proposals:
Things changed in the 21st century after two presidential administrations made fateful decisions regarding NASA. The first came in 2004 when President George W. Bush announced the “Vision for Space Exploration“. This involved retiring the Space Shuttle and developing a new class of launchers that could take humans back to the Moon by 2020 – known as the Constellation Program.
Then, in February of 2010, the Obama administration announced that it was cancelling the Constellation Program and passed the Authorization Act of 2010. Intrinsic to this plan was a Mars Direct mission concept, which called for the development of the necessary equipment and systems to mount a crewed mission to Mars by the 2030s.
In 2015, NASA’s Human Exploration and Operations Mission Directorate (HEOMD) presented the “Evolvable Mars Campaign”, which outlined their plans for their “Journey to Mars’ by the 2030s. Intrinsic to this plan was the use of the new Orion Multi-Purpose Crew Vehicle (MPCV) and the Space Launch System (SLS).
The proposed journey would involve Three Phases, which would involve a total of 32 SLS launches between 2018 and the 2030s. These missions would send all the necessary components to cis-lunar space and then onto near-Mars space before making crewed landings onto the surface.
Phase One (the “Earth Reliant Phase”) calls for long-term studies aboard the ISS until 2024, as well as testing the SLS and Orion Crew capsule. Currently, this involves the planned launch of Exploration Mission 1 (EM-1) in Sept. of 2018, which will be the first flight of the SLS and the second uncrewed test flight of the Orion spacecraft.
NASA’s Journey to Mars. NASA is developing the capabilities needed to send humans to an asteroid by 2025 and Mars in the 2030s. Credit: NASA/JPL
NASA also plans to capture a near=Earth asteroid and bring it into lunar orbit, as a means of testing the capabilities and equipment for a Mars mission. Known as the Asteroid Redirect Mission, this mission is scheduled to take place in the 2020s and would primarily involve a robotic mission towing the asteroid and returning samples.
Exploration Mission 2 (EM-2), the first crewed flight using the Orion capsule, would conduct a flyby around the Moon and this asteroid between 2021 and 2023. At this point, NASA would be moving into Phase Two (“Proving Ground”) of the Journey to Mars, where the focus would move away from Earth and into cis-lunar space.
Multiple SLS launches would deliver the mission components during this time – including a habitat that would eventually be transported to Martian orbit, landing craft, and exploration vehicles for the surface of Mars. This phase also calls for the testing of key technologies, like Solar Electric Propulsion (aka. the ion engine).
By the early 2030s, Phase Three (“Earth Independent”) would begin. This calls for testing the entry, descent and landing techniques needed to get to the Martian surface, and the development of in-situ resource utilization. It also calls for the transferring of all mission components (and an exploration crew) to Martian orbit, from which the crews would eventually mount missions to designated “Exploration Zones” on the surface.
The European Space Agency (ESA) has long-term plans to send humans to Mars, though they have yet to build a manned spacecraft. As part of the Aurora Program, this would involve a crewed mission to Mars in the 2030s using an Ariane M rocket. Other key points along that timeline include the ExoMars rover (2016-2020), a crewed mission to the Moon in 2024, and an automated mission to Mars in 2026.
Roscosmos, the Russian Federal Space Agency, is also planning a crewed mission to Mars, but doesn’t envision it happening until between 2040 and 2060. In the meantime, they have conducted simulations (called Mars-500), which wrapped up in Russia back in 2011. The Chinese space agency similarly has plans to mount a crewed mission to Mars between 2040 and 2060, but only after crewed missions to Mars take place.
In 2012, a group of Dutch entrepreneurs revealed plans for a crowdfunded campaign to establish a human Mars base, beginning in 2023. Known as MarsOne, the plan calls for a series of one-way missions to establish a permanent and expanding colony on Mars, which would be financed with the help of media participation.
Other details of the MarsOne plan include sending a telecom orbiter by 2018, a rover in 2020, and the base components and its settlers by 2023. The base would be powered by 3,000 square meters of solar panels and the SpaceX Falcon 9 Heavy rocket would be used to launch the hardware. The first crew of 4 astronauts would land on Mars in 2025; then, every two years, a new crew of 4 astronauts would arrive.
SpaceX and Tesla CEO Elon Musk has also announced plans to establish a colony on Mars in the coming decades. Intrinsic to this plan is the development of the Mars Colonial Transporter (MCT), a spaceflight system that would rely of reusable rocket engines, launch vehicles and space capsules to transport humans to Mars and return to Earth.
As of 2014, SpaceX has begun development of the large Raptor rocket engine for the Mars Colonial Transporter, and a successful test was announced in September of 2016. In January 2015, Musk said that he hoped to release details of the “completely new architecture” for the Mars transport system in late 2015.
In June 2016, Musk stated in the first unmanned flight of the MCT spacecraft would take place in 2022, followed by the first manned MCT Mars flight departing in 2024. In September 2016, during the 2016 International Astronautical Congress, Musk revealed further details of his plan, which included the design for an Interplanetary Transport System (ITS) – an upgraded version of the MCT.
According to Musk’s estimates, the ITS would cost $10 billion to develop and would be ready to ferry the first passengers to Mars as early as 2024. Each of the SpaceX vehicles would accommodate 100 passengers, with trips being made every 26 months (when Earth and Mars are closest). Musk also estimated that tickets would cost $500,000 per person, but would later drop to a third of that.
And while some people might have a hard time thinking of MarsOne’s volunteers or SpaceX’s passengers as astronauts, they would nevertheless be human beings setting foot on the Red Planet. And if they should make it there before any crewed missions by a federal space agency, are we really going to split hairs?
So the question remains, when will see people sent to Mars? The answer is, assuming all goes well, sometime in the next two decades. And while there are plenty who doubt the legitimacy of recent proposals, or the timetables they include, the fact that we are speaking about going to Mars a very real possibility shows just how far we’ve come since the Apollo era.
And does anyone need to be reminded that there were plenty of doubts during the “Race to the Moon” as well? At the time, there were plenty of people claiming the resources could be better spent elsewhere and those who doubted it could even be done. Once again, it seems that the late and great John F. Kennedy should have the last word on that:
“We choose to go to the Moon! … We choose to go to the Moon in this decade and do the other things, not because they are easy, but because they are hard; because that goal will serve to organize and measure the best of our energies and skills, because that challenge is one that we are willing to accept, one we are unwilling to postpone, and one we intend to win.”
If you’d like more information about humans traveling to Mars, check out the Mars Society’s homepage. And here’s a link to MarsDrive, and another group looking to send people to Mars.
Mars from orbit. Valles Marineris and Volcanic region
Given it’s similarities to Earth, Mars is often referred to as “Earth’s Twin”. Like Earth, Mars is a terrestrial planet, which means it is composed largely of silicate rock and minerals that are differentiated into a core, mantle and crust. It is also located within the Sun’s “Goldilocks Zone” (aka. habitable zone), has polar ice caps, and once had flowing water on its surface. But beyond these, Mars and Earth are very different worlds.
In addition to their stark contrasts in temperature, surface conditions, and exposure to harmful radiation, Mars also takes a significantly longer time to complete a single orbit of the Sun. In fact, a year on Mars is almost twice as long as a year here on Earth – lasting 686.971 days, which works out to about 1.88 Earth years. And in the course of that orbit, the planet undergoes some rather interesting changes.
[/caption]I think that one of the most interesting questions that have been posed of late is ‘what is Mar’s atmosphere made of?’ There has been a great deal of study done on this topic and interest is increasing since the discovery of methane, a possible indicator of life.
The atmosphere of Mars is over 95% carbon dioxide, 95.32% to be exact. The breakdown of gases goes like this:
Carbon dioxide 95.32%
Nitrogen 2.7%
Argon 1.6%
Oxygen 0.13%
Carbon monoxide 0.07%
Water vapor 0.03%
Nitric oxide .0013%
Trace gases(including krypton, methane, etc)
The Martian atmosphere has four main layers: lower, middle, upper, and exosphere. The lower atmosphere is a warm region(around 210 K). It is warmed by airborne dust(1.5 micrometers across) and heat radiated from the surface. This airborne dust gives the planet its ruddy brown appearance. The middle atmosphere is features a jetstream similar to Earth’s. The upper atmosphere is heated by the solar wind and the temperatures are much higher than at the surface. This heat separates the gases. The exosphere starts at about 200 km and has no clear end. It just tapers off into space.
The carbon dioxide in the atmosphere freezes for part of the year and may drop to the surface. As much as 25% of the atmospheric carbon dioxide condenses at the polar caps into solid ice(dry ice) because the Martian poles are not exposed to sunlight during the planet’s winter. When the poles are again exposed to sunlight, the ice returns to its gas form and rises back into the atmosphere. So, a significant annual variation in the atmospheric pressure and atmospheric composition around the Martian poles.
The methane mentioned earlier is used to show the possibility of life on Mars. While it is a byproduct of life, it is also a result of volcanism, geothermal process, and hydrothermal activity. Methane is an unstable gas, so there has to be a source on the planet that is constantly replenishing it. It has to be a very active source, because studies have shown that the methane is destroyed in less than on Earth year. It is thought that peroxides and perchlorates in the soil or that it condenses and evaporates seasonally from clathrates.
Now you answer ‘ what is Mar’s atmosphere made of?’ the next time it comes up. You can be sure that the methane component will continue to be studied by rovers, orbiters, and, in the future, astronauts.
We have written many articles about the atmosphere of Mars for Universe Today. Here’s an article about the air on Mars, and here’s an article about Mars’ comparison with Earth.
The Mars Global Surveyor was a spacecraft sent to Mars in 1996. It arrived at Mars and studied the planet for 10 years, until it broke down in 2006, and controllers on Earth lost contact with it. But while it was operating, the spacecraft took thousands of images, and made some major discoveries about Mars.
Mars Global Surveyor was launched on November 7, 1996, and made its orbital insertion on September 11, 1997. It used a technique called aerobraking to reduce its orbit and bring it into an orbit that brought it to an average distance of 378 km from the surface of Mars. It circled the planet in a polar orbit once every 117 minutes, which allowed it to photograph the entire Martian surface.
The spacecraft was equipped with 5 major scientific instruments: Mars Orbiter Camera, Mars Orbiter Laser Altimeter, Thermal Emission Spectrometer, Magnetometer and electron reflectometer and the Ultrastable Oscillator for Doppler measurements. These instruments allowed the spacecraft to study the atmosphere and surface composition of Mars. But it also sent back the highest resolution photographs ever seen of Mars. The newer Mars Reconnaissance Orbiter has returned better images with its larger telescope, but when the first MGS images first came back from Mars, they were stunning.
It made some incredible discoveries about Mars. Thanks to the observations from MGS, astronomers determined that Mars had a layered crust that was more than 10 km thick. It found ancient craters that had been buried and then later exposed by erosion, and it found evidence of ancient lava flows.
But perhaps the biggest discovery was made in 2006, which researchers announced that they had uncovered evidence of recent water activity on Mars. Images from the Mars Global Surveyor showed gullies on Mars which looked like they’d been formed by water. It’s possible that water had erupted out of an underground aquifer and spilled down the slope of a hill before evaporating in the pressure of the Martian atmosphere.
After a decade of service, Mars Global Surveyor went silent on November 2, 2006. It went into safe mode after being issued commands to change the orientation of its solar panels, and it stopped communicating. NASA said that it was, “battery failure caused by a complex sequence of events involving the onboard computer memory and ground commands.” But we’ll never really know what happened to it.
Mars and Venus are the two terrestrial planets most similar to Earth. One orbits closer to the Sun, and one orbits more distant to the Sun. But both are visible with the unaided eye, and two of the brightest objects in the night sky.
Venus orbits at an average distance of only 108 million km from the Sun, while Mars is an average of 228 million km. Venus gets as close to Earth as 38 million km, and Mars gets as close as 55.7 million km.
In terms of size, Venus is almost a twin planet of Earth. Its diameter is 12,104 km, which is 95% the diameter of Earth. Mars is much smaller, with a diameter of only 6,792 km. And again, in terms of mass, Venus is almost Earth’s twin. It has 81% the mass of Earth, while Mars only has 10% the mass of Earth.
The climates of Mars and Venus are very different, and very different from Earth as well. Temperatures on the surface of Venus average 461 °C across the entire planet. That’s hot enough to melt lead. While the average temperature on Mars is a chilly -46 °C. This temperature difference comes from the fact that Venus is closer to the Sun, but also because it has a thick atmosphere of heat trapping carbon dioxide. The atmosphere on Venus is nearly 100 times thicker than Earth’s atmosphere at sea level, while the atmosphere on Mars is 1% the thickness of Earth.
Mars is the most studied planet in the Solar System (after the Earth). There have been dozens of missions sent to Mars, including orbiters and rovers. Although many missions have been lost, there have been several that have successfully orbited the planet and several that have landed on the surface. Missions have also been sent to Venus, and you might be surprised to know that the Soviets sent a series of landers called Venera that actually reached the surface of Venus and survived long enough to send back a few photographs.
Mars has two moons, Phobos and Deimos, while Venus has no moons. And neither planet has rings.
This full-circle view from the panoramic camera (Pancam) on NASA's Mars Exploration Rover Spirit shows the terrain surrounding the location called "Troy," where Spirit became embedded in soft soil during the spring of 2009. Credit: NASA/JPL
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It is impossible to know the answer to ”when was Mars discovered”. It is bright enough to be seen in the night sky without binoculars or a telescope and has been documented for at least 4,000 years.
If you were to change the question a little to ”who first theorized that Mars was a planet”, then an answer can be found. Nicolaus Copernicus is the first astronomer to postulate that Mars and a few other bodies known at the time were planets. The heliocentric theory that he published in 1543 marked the first time that astronomers widely considered the possibility that the Sun was the center of the Solar System instead of the Earth.
While no one knows who first discovered Mars, we do know who made many of the discoveries about the planet. It is known that Tycho Brahe, a Danish astronomer made accurate calculations of the position of Mars as early as 1576. Johannes Kepler theorized that the orbit of Mars was elliptical in contradiction to what astronomers believed at the time. He soon expanded that theory to encompass all planets. In 1659, Christian Huygens, a Dutch astronomer drew Mars with the observations he made using a telescope he designed himself. He also discovered a strange feature on the planet that became known as Syrtis Major.
On November 28, 1964, Mariner 4 was launched successfully on an eight-month voyage to the Red Planet. It made its first flyby on July 14, 1965, collecting the first close-up photographs of another planet. The pictures showed many impact craters, some of them touched with frost in the chill Martian evening. The Mariner 4 spacecraft was able to function for about three years in solar orbit, continuing long-term studies of the solar wind environment and making coordinated measurements with Mariner 5.
There are currently six spacecraft in orbit around Mars or on its surface and several more are in the planning or design stages. Five are gathering data at an amazing rate, the other(Phoenix) is non-functioning. New discoveries like subsurface water ice and methane plumes in the atmosphere are being made on a regular basis. Scientists may not be able to give an answer to ”when was Mars discovered”, but they can offer answers to thousands of other questions and the list is growing as we speak.
