History of Mars in Timeline

Mars is the fourth planet from the Sun and is known as the "Red Planet" due to the iron(III) oxide on its surface. It's a terrestrial planet, the second smallest in the Solar System, with a diameter of 6,779 km. A Martian solar day is 24.6 hours, and a year is 1.88 Earth years. Mars is bright and easily viewed through telescopes due to its high-contrast albedo features. It has two small, irregularly shaped moons: Phobos and Deimos.

1909: Observations by Antoniadi with 84-cm telescope

During observations in 1909 by Antoniadi with an 84-centimetre telescope, irregular patterns were observed on Mars, but no canali were seen.

1909: Study Repeated by Campbell and Slipher

In 1909, Campbell and V. M. Slipher repeated a study using better instruments, but had the same results.

1925: Findings Confirmed by W. S. Adams

It was not until the findings were confirmed by W. S. Adams in 1925 that the myth of the Earth-like habitability of Mars was finally broken.

1938: Publication of C.S. Lewis's "Out of the Silent Planet"

In 1938, C.S. Lewis's novel "Out of the Silent Planet", depicting Mars, was published.

1948: Appearance of Marvin the Martian

In 1948, Marvin the Martian, a comic figure of an intelligent Martian, appeared in Haredevil Hare as a character in the Looney Tunes animated cartoons of Warner Brothers.

November 1964: Launch of Mariner 4

NASA's Mariner 4 was launched on 28 November 1964, becoming the first spacecraft to visit Mars.

July 1965: Mariner 4's closest approach to Mars

On 15 July 1965, Mariner 4 made its closest approach to Mars, detected a weak radiation belt, and captured the first images of another planet from deep space.

1965: First flyby by Mariner 4

In 1965, the Mariner 4 probe performed the first flyby of Mars.

1971: First orbit by Mars 2 probe

In 1971, the Mars 2 probe became the first spacecraft to orbit Mars.

1972: Selection of Airy-0 crater as Prime Meridian

In 1972, after Mariner 9 provided extensive imagery, Airy-0 crater was chosen to define 0.0° longitude.

1976: First landing by Viking 1 probe

In 1976, the Viking 1 probe achieved the first successful landing on Mars.

1996: Launch of Mars Global Surveyor

The Mars Global Surveyor mission launched in 1996, producing detailed maps of the Martian topography, magnetic field and surface minerals.

1999: Hypothesis of plate tectonics on Mars

In 1999, a hypothesis suggested that alternating polarity reversals indicate plate tectonic activity on Mars four billion years ago.

2001: 2001 Mars Odyssey in orbit

As of 2023, 2001 Mars Odyssey is one of eight orbiters currently around Mars.

2003: Mars comes into opposition

Mars came into opposition from Earth near its perihelion in 2003.

2004: Opportunity detects jarosite

In 2004, the Opportunity rover detected the mineral jarosite, which forms in the presence of acidic water, indicating past water on Mars.

October 2005: Re-examination of plate tectonics hypothesis

In October 2005, the hypothesis of plate tectonic activity on Mars was re-examined using data from the Mars Global Surveyor.

2006: End of Mars Global Surveyor mission

The Mars Global Surveyor mission, which launched in 1996, operated until late 2006, producing complete, extremely detailed maps.

2007: Spirit rover finds concentrated silica deposits

In 2007, the Spirit rover found concentrated deposits of silica, further indicating wet conditions in Mars's past.

December 2011: Discovery of gypsum by Opportunity

In December 2011, NASA's Mars rover Opportunity found the mineral gypsum, which forms in the presence of water, on the surface of Mars.

2012: Valles Marineris proposed as plate boundary

In 2012, it was proposed that Valles Marineris is a plate boundary with transverse motion, suggesting a two-tectonic plate arrangement on Mars.

March 2013: Evidence of mineral hydration reported

On 18 March 2013, NASA reported evidence from the Curiosity rover of mineral hydration, likely hydrated calcium sulfate, in several rock samples.

2014: Analysis of Martian meteorite EETA79001

In 2014, an analysis of the Martian meteorite EETA79001 revealed the presence of chlorate, perchlorate, and nitrate ions at concentrations suggesting their widespread presence on Mars. The analysis also indicated that UV and X-ray radiation would convert chlorate and perchlorate ions into highly reactive oxychlorines, meaning that organic molecules would have to be buried to survive.

March 2015: Scientists state ocean might have been size of Earth's Arctic Ocean

In March 2015, scientists stated that an ocean on Mars might have been the size of Earth's Arctic Ocean, based on the ratio of protium to deuterium.

September 2015: Evidence of hydrated brine flows found

In September 2015, NASA announced they had found strong evidence of hydrated brine flows in recurring slope lineae.

November 2016: Discovery of large underground ice deposit

In November 2016, NASA reported finding a large amount of underground ice in the Utopia Planitia region, estimated to be equivalent to the volume of water in Lake Superior.

September 2017: Radiation levels doubled due to aurora

In September 2017, NASA reported radiation levels on Mars doubled due to an aurora 25 times brighter than any observed earlier, caused by a solar storm.

2017: NASA directed to study crewed Mars mission feasibility

In 2017, the NASA Authorization Act directed NASA to study the feasibility of a crewed Mars mission in the early 2030s, but the resulting report eventually concluded that this would be unfeasible.

2018: ExoMars Trace Gas Orbiter spots water

During observations from 2018 through 2021, the ExoMars Trace Gas Orbiter spotted indications of water in the Valles Marineris canyon system.

2018: Mars comes into opposition

Mars came into opposition from Earth near its perihelion in 2018.

2019: Detection of marsquakes by InSight

In 2019, it was reported that InSight had detected and recorded over 450 marsquakes and related events, confirming Mars is seismically active.

2020: Mars comes into opposition

The planets came into opposition near Mars's perihelion in 2020.

2021: ExoMars Trace Gas Orbiter spots water

During observations from 2018 through 2021, the ExoMars Trace Gas Orbiter spotted indications of water in the Valles Marineris canyon system.

2021: China plans for crewed Mars mission

In 2021, China was planning to send a crewed Mars mission in 2033.

April 2023: Updated global map of Mars reported

In April 2023, The New York Times reported an updated global map of Mars based on images from the Hope spacecraft and NASA released a more detailed map.

2023: Evidence of ancient ring system

A 2023 study based on the orbital inclination of Deimos, suggests Mars may have had a ring system 3.5 to 4 billion years ago.

2023: Active spacecraft on Mars in 2023

As of 2023, Mars hosts ten functioning spacecraft, including eight orbiters and two rovers on the surface.

2023: Active Mars probes in 2023

As of 2023, there are at least 11 active probes orbiting Mars or on the Martian surface.

February 2024: Space mission debris accumulates

As of February 2024, debris from Mars missions has reached over seven tons, consisting of crashed spacecraft, inactive components and discarded parts.

April 2024: SpaceX plans for Mars colonization

In April 2024, Elon Musk shared SpaceX's plans envisioning the beginning of a Mars colony within the next twenty years, enabled by mass manufacturing of Starship and initially sustained by resupply from Earth and in situ resource utilization on Mars.

April 2024: NASA selects companies for commercial services

In April 2024, NASA selected several companies to begin studies on providing commercial services to further enable robotic science on Mars, including telecommunications and surface imaging.

June 2024: Cheyava Falls rock designated a "potential biosignature"

In June 2024, NASA designated the Cheyava Falls rock on Mars as a "potential biosignature." The Perseverance rover took a core sample for possible return to Earth and further examination, but no definitive determination on a biological or abiotic origin of this rock can be made with current data.