Does it rain diamonds on Mars? Our fascination with Mars stems from our desire to learn more about its intriguing history and its place in the cosmos.
But could there be a dazzling phenomenon among the swirling dust storms and craggy terrain that would cause even the most jaded space enthusiast to gasp in awe?
Get ready for an exciting adventure as we investigate the intriguing question of whether or not diamonds actually do rain on Mars.
Is it really possible? Can it rain diamonds on Mars?
No, it cannot rain diamonds on Mars because there is not enough carbon in the atmosphere or high enough temperatures for diamonds to form and precipitate on Mars.
The Concept of Raining Diamonds
The idea of raining diamonds on planets is not new. It first hit the world in 1981, when Marvin Ross talked about it.
In his article entitled, The Ice Layer of Uranus and Neptune—Diamonds in the Sky? he suggested something awesome.
What he suggested was that carbon and hydrogen atoms of hydrocarbons like methane would separate under the high pressures and temperatures inside ice giants.
The isolated carbon would clump and be squeezed into diamonds, the most stable form of carbon available in the conditions.
Fact: Winter nights on Mars can go as cold as -220 degrees Fahrenheit, but summer days near the equator can reach 70 degrees Fahrenheit.
Overview of Martian Weather
Mars has a very thin atmosphere of mostly carbon dioxide which has a very poor greenhouse effect and barely protects the planet from the constant bombardment of cosmic rays.
Weather is dynamic and seasonal and windstorms are usual; some circle the planet.
These winds reach such high speeds they strip the red dust that is the Martian soil, off the bedrock.
There is water vapor and signs of water erosion. The sky is cloudy and rich in particles that absorb light and warm the atmosphere.
Fact: The sky is not clear on Mars but at night it is cold and when conditions are ripe, water-ice clouds form and snow falls on Mars.
Does It Rain Diamonds on Mars?
Extra-terrestrial diamonds are surprisingly common, forming in stars before the solar system and present in meteorites, raising the possibility of diamonds on Mars.
Earthbound experiments on methane gas under very high pressure successfully produced nanodiamonds.
This suggests that the process is theoretically possible where there are enough hydrocarbons available.
For diamond to form on Mars, certain things need to be in place, such as:
Temperature and Pressure Conditions
At around – 81o F on average and with very low air pressure, Mars lacks the extreme conditions that characterize the gas giants’ atmospheres and which laboratory testing confirm are needed to split the hydrocarbons to make diamonds.
It also lacks the hot dense layers of the atmosphere where the process of diamond formation is speculated to happen.
The idea of diamond rain includes time spent falling through the pressurized atmosphere, which is impossible on Mars.
Availability of Carbon
There is carbon on Mars.
Mars’ atmosphere is primarily composed of carbon dioxide, nitrogen and argon gases with oxygenized dust particles blown up from the surface.
Nonetheless, there is organic matter, carbon, hydrogen, possibly oxygen and nitrogen, either left over from when the planet had life or delivered by meteorites.
Curiosity rover found them in a 3-billion-year-old rock, although it could not tell where they had come from. Rover also confirmed the presence of methane.
Potential Diamond Formation Mechanisms
There is no shortage of hydrocarbon mixtures in the universe. They are in abundant supply.
It is believed diamond formation could be an essential process in planet formation, shaping its internal structure.
The ‘diamonds in the sky’ idea suggests that diamonds form in the mantles of Uranus and Neptune.
Meteorite Impact
There is the suggestion that the hydrocarbons were delivered by meteorites.
In 2022 researchers concluded that diamonds had formed around 50,000 years ago during a high-energy shock wave from an asteroid collision.
The short-term blast at high temperatures and sudden extreme pressure gave the diamonds unique properties.
Named lonsdaleite diamonds, they are nanostructured with diaphites, intergrowths of two mineral crystals.
Their study brings science closer to understanding the pressure-temperature conditions during asteroid impacts.
Volcanic Activity
The discovery of diaphites in diamonds is exciting because diamonds are typically made of pure carbon.
Because the carbon is crystalized under pressure and subjected to temperatures over 1000 degrees, they are extremely stable and hard.
On earth, we know diamonds form at around 180km below the planet’s surface in the mantle and are transported by magmas called kimerlites.
These magmas are ejected by volcanoes and cool into rock with the diamonds occluded in them.
Diamond Formation in the Atmosphere
We may not have diamonds precipitating out of the Earth’s atmosphere.
But, in the upper layers of other planets, atmospheric conditions are closer to those inside an Earth volcano which invites speculation.
The theory speculates they form like rain, and cycle between the lower and upper layers.
They respond to the changing temperatures and pressures transforming from solid high up to liquid low down in much the same way our water cycles around Earth.
Analyzing the “Diamond Rain” Hypothesis
The Diamond Rain Hypothesis has enough value to prompt expensive research that might positively impact the quality of the industrial diamonds already produced.
The hypothesis accounts for the carbon needed and the high temperature-pressure formation process.
It stands up in light of what we know about hydrocarbons, diamonds and planetary atmospheres.
The hypothesis was tested and reported on in Nature.
Results supported the shock wave theory demonstrating that shock waves can fracture methane molecules to free the carbon atoms for diamond formation.
An Important Consideration
Observation of the process revealed how the atoms clump together and grow heavy.
In an atmosphere, they would descend into the increasing temperatures and pressures to be transformed into diamonds on the way.
However, the experiment couldn’t recreate these more extreme conditions to be sure.
Alternative Explanations for Diamond-like Observations on Planets
Building on this work and further research, including observations by Cassini, diamond should be the most stable form of carbon in the interior of the gas giants.
Cassini’s observation of lightning on Saturn prompted the theory that the carbon is pulled from the methane, the bolts’ shock wave and heat tearing the molecules apart.
Fact: Diamond melts at about 8000oK on Jupiter and Saturn but whether it melts to liquid diamond or graphite is uncertain.
Extra-terrestrial Diamond Rain: Reality or Myth?
We know now that Uranus and Neptune do not have core temperatures high enough to melt diamonds.
And it turns out that graphite is the most stable carbon in Saturn’s upper atmosphere.
Therefore, there is doubt about the reality of diamond rain on other planets. White dwarfs are another thing.
Simulations show their carbon atoms line up perfectly for crystallization. The discovery of an exoplanet, 55 Cancri e, with a solid diamond core supported the observation.
Confirmed Cases of Diamond Rain on Celestial Bodies
We know of other diamond-cored bodies, V886 Centauri and BPM 37093, the famed Lucy.
This white dwarf is possibly the largest natural diamond ever created.
We also know diamonds are formed in Neptune and Uranus in a superhot, superdense fluidic mixture of water, methane, and ammonia – below the atmosphere.
Jupiter and Saturn
Jupiter’s core is too hot for solid diamonds to exist.
The conditions in the vast depths of its atmosphere could be so extreme that it has oceans of liquid diamonds.
Lab-based experiments and theoretical calculations suggest both have solid diamond particles floating deep inside them and that Saturn should have a thin diamond layer.
Fact: On Saturn, solid diamonds should present between 4,000 and 23,000 miles below the cloud tops or halfway down into the planet.
Lessons Learned from These Cases
If there is a lesson about speculating on the processes of distant planets, it is to stay humble.
We are learning and with every fly past, we get better first-hand evidence.
When the idea of diamond rain was first proposed it married well with experience of how diamonds form and processes on Earth work.
But, the atmospheric conditions that affect them are unique to each planet. Still, the idea of diamond rain motivated science to go take a look.
Takeaway
Does it rain diamonds on Mars? While the thought of diamonds raining down on Mars is fascinating, there is no evidence to support the idea that this actually occurs.
Carbon dioxide dominates Mars’s sparse atmosphere, which also contains traces of nitrogen and argon.
If you compare this composition to, say, the atmospheres of Jupiter or Saturn, you will see that diamond rain on these planets is an entirely different ballgame.
