By: Ken Kellar
A new study of one of our interstellar neighbours is helping to support a theory there may be water elsewhere in our solar system.
NASA this week announced the findings of an observational campaign of Jupiter’s icy moon Europa, where scientists have determined that there is strong evidence to support the existence of vapour plumes on the gas giant’s moon.
The space agency hosted a live media call Monday afternoon to discuss the findings of the campaign undertaken by the Hubble Space Telescope in 2014.
The campaign used the Hubble telescope to examine Europa as it crossed the surface of Jupiter and studied the much smaller body against its parent’s backlight, picking up the changes in the light given off by Jupiter to look for the plumes.
It also examined the two by measuring ultraviolet radiation.
“I think everyone is interested in the question of whether there’s life elsewhere in the universe.” – David Hanes
According to a previous study released by NASA, scientists believe that under a layer of ice several kilometres thick, Europa might be hiding deep saltwater oceans.
The new findings help to support this theory, as well as provide new strategies for studying this ocean when NASA begins its Europa mission to study the distant body. That mission is currently expected to begin sometime in the 2020s.
How there might be water on Europa
David Hanes is a professor of astronomy and astrophysics at Queen’s University. He explains how an icy moon like Europa could have liquid water when it and Jupiter are five times farther from the sun than Earth.
“Europa is going in its orbit around and around Jupiter,” said Hanes, “and it experiences tidal stresses because of the gravity of Jupiter, and that sort of kneads and distorts the moon and heats it up, the same way you might take a squash ball and squeeze it in your hand before a squash game to get it a bit warm.
“So that keeps the liquid oceans liquid, if they are indeed there.”
As vapour plumes become more likely to exist, NASA has the additional options of dropping some kind of probe into a vent to study the hypothesized ocean, or to land a probe on the surface of Europa to study what the plumes spew out as they fall back to the moon’s surface.
An additional study released by NASA has proposed that Europa’s oceans might also have a chemical balance that could potentially provide enough energy to support life of some kind.
Hanes said that the possibility of this ocean having the necessary ingredients for life is what captures the public’s imagination.
“I think everyone is interested in the question of whether there’s life elsewhere in the universe,” Hanes said.
“If we discovered that, within our solar system, there were life forms on this moon of Jupiter as well as on Earth, what that tells you is that life must spring up essentially everywhere there’s a suitable location,” he told Humber News.
“It could be that the emergence of life is remarkably rare, but if we discovered that on a nearby planet in our own solar system, that life had independently come into existence, then that would be a sign that it’s really all over the place,” he said.
“Everyone is interested in that question, but if we could ever find evidence that there’s other civilizations out there, that would cause quite a shift in the way we think about ourselves and the universe.”
Hanes enforced that the recent observations of the vapour plumes in no way speaks to the possibility of life existing on Europa, only that the possibility exists thanks to the reinforced evidence of liquid water within the planet.
Europa is the fourth largest of the 67 known moons that orbit Jupiter.
It is also one of the four moons discovered by Galileo Galilei in January 2016, collectively referred to as the Galilean moons.