What does Saturn SMELL like? Nasa creates the 'sweet aromatic' scent of the planet's Titan moon using gases in its atmosphere
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In an episode of animated series Futurama, Professor Farnsworth unveiled a contraption known as the 'Smell-O-Scope', which let users 'smell' distant stars and planets.
Although billed as a fictional device, Nasa scientists claim to have developed a similar system and have used it capture the 'flavours' of Saturn's moon Titan.
By replicating Titan's atmosphere in a lab, they were able to work out what Titan's atmosphere is made from, and the technique could be used to discover the composition of other worlds as well.
Nasa scientists have recreated the 'scent' of Saturn's moon Titan (pictured in ultraviolet and infrared) by combining gases in a lab and letting them react. This helped to determine the identity of a material that had been detected in the atmosphere by the Cassini spacecraft, which is now thought to be benzene
In the experiment, researchers at Nasa's Goddard Space Flight Center in Maryland recreated Titan's atmosphere in a lab by mixing different gases thought to make up its hazy exterior.
TITAN: SATURN'S LARGEST MOON
With its thick atmosphere and organic-rich chemistry, Titan resembles a frozen version of Earth, several billion years ago, before life began pumping oxygen into our atmosphere.
Because Titan is less massive than Earth, its gravity doesn't hold onto its gaseous envelope as tightly, so the atmosphere extends 370 miles (600 kilometres) into space.
As on Earth, the climate is driven mostly by changes in the amount of sunlight that come with the seasons, although the seasons on Titan are about seven Earth years long.
Titan's 'water' is liquid methane, CH4, better known on Earth as natural gas. Regular Earth-water, H2O, would be frozen solid on Titan where the surface temperature is -180°C (-290°F).
With Titan's low gravity and dense atmosphere, methane raindrops could grow twice as large as Earth's raindrops. As well as this, they would fall more slowly, drifting down like snowflakes.
Scientists think it rains perhaps only every few decades.
Two of these, namely nitrogen and methane, were previously known, but the third component that had been detected was a mystery.
Through a method of trial-and-error, they eventually found their best attempts at mimicking the atmosphere occurred when their third gas was benzene - most commonly found in gasoline.
The process was not entirely dissimilar to how a chef tastes a dish and works out what ingredients were used in the recipe.
By trying different gases, the researchers were able to create an artificial atmosphere that matched the signature of Titan's real atmosphere.
Benzene is what is known as an aromatic hydrocarbon, and it's a sweet-smelling compound.
However, the researchers warned that because of Titan's immense surface pressure, people would have a hard time smelling it on the surface.
'Now we can say that this material has a strong aromatic character, which helps us understand more about the complex mixture of molecules that makes up Titan's haze,' said Melissa Trainer, a planetary scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland.
In the research scientists aimed to create an 'atmosphere' that mimicked the signature of Titan's as shown in this graph. To do so scientists had to experiment with different gases until benzene was found to give the same signature. The process was similar to how a chef works out the ingredients in food by tasting it
In the animated television series Futurama, Professor Farnsworth creates a comical 'Smell-O-Scope' (pictured) that lets him and his crew 'smell' the composition of distant stars and worlds, used in one scene to spot a rip in space-time. Nasa's lab experiment, while less impressive-looking, surprisingly used a similar principle
Previous attempts to recreate Titan's atmosphere in a laboratory have seen limited success, as aside from nitrogen and methane it was not well-known what it is composed of.
This new method of combining gases and letting them react gives astronomers a better understanding of this Earth-like world, so labelled because of its thick atmosphere and surface lakes and seas.
'Titan's chemical makeup is veritable zoo of complex molecules,' added Scott Edgington, Cassini Deputy Project Scientist at NASA's Jet Propulsion Laboratory in Pasadena, California.
'With the combination of laboratory experiments and Cassini data, we gain an understanding of just how complex and wondrous this Earth-like moon really is.'
It is feasible this same method could be used to work out the composition of atmospheres on other worlds - including, most intriguingly, those of potentially-habitable planets outside the solar system.
This would help astronomers work out if a particular exoplanet contains the right atmospheric ingredients for life to exist.
Nasa's Cassini spacecraft (illustration shown) has been orbiting Saturn and its moons since 1 July 2004. The probe has been a huge success, revealing untold secrets of the Saturnian system including liquid oceans on Titan's surface, huge storms on Saturn and geysers on the icy moon Enceladus
Most of what we know to date about Titan comes from Nasa's Cassini spacecraft, which has been orbiting the Saturnian system since 1 July 2004.
However, while Cassini has imaged the surface and studied the atmosphere of Titan, it had been unable to identify a material in the moon's smoggy haze.
Now thanks to this research astronomers have a better understanding on what this world is made of.
The mystery material was first detected by Cassini's Composite Infrared Spectrometer, an instrument that makes observations in the infrared.
'This is the closest anyone has come, to our knowledge, to recreating with lab experiments this particular feature seen in the Cassini data,' said lead author of the study Joshua Sebree.
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