Harvard astrophysicist Abraham Loeb gets the feeling that we are one of the last to the universe party. Loeb’s research suggests that a mere 15 million years after the Big Bang, alien microbes might have happily survived.
“When the universe was 15 million years old, the cosmic microwave background had a temperature of a warm summer day on Earth. If rocky planets existed at that epoch, then the CMB could have kept their surface warm even if they did not reside in the habitable zone around their parent star.”
He suggests “searching for planets with atmospheric bio-signatures around low-metallicity stars in the Milky Way galaxy or its dwarf galaxy satellites.” In essence, if researchers find planets in the vicinity of stars that have merely a few heavy elements, then these might once have been analogous to the very earliest of planets.
Understanding what may or may not have happened billions of years ago is not exactly a simple task. But one sign that Loeb might be onto something is that his fellow scientists aren’t pooh-poohing it. Water might have existed in many more places than first imagined. So who knows who or what might have existed in times gone far by?
And who knows what might still exist and be visiting us regularly, only to leave, shaking their heads and bodies in derision?
NASA might not have found life on Mars but the search has expanded beyond that. In its latest budget request the US space agency set aside funds to explore a mission to Jupiter’s moon Europa, which is considered as one of the solar system’s best bets for hosting alien life.
Nasa’s annual federal budget request of $17.5 billion (down by $1.2 billion from its 2010 peak) has set aside $15 million for “pre-formulation work” on a mission to the moon, with plans to make detailed observations and possibly sample its interior oceans.
Scientists believe that underneath Europa’s icy exterior is a single, massive ocean that contains almost twice as much water as is found on Earth, kept liquid by the gravitational pull of Jupiter – a force that creates tidal swells 1,000 times stronger than those caused by our own Moon.
The possibility of life existing without sun has now found credibility while earlier it was believed that life is not possible without it. This was after diverse organisms including tube worms and shrimp found around the deep-sea hydrothermal vents known as ‘black smokers’, were discovered.
In addition to the possibility of life under the ice, observations made late last year by the Hubble telescope suggest that enormous jets of water some 200 kilometres tall (that’s twice as high as Earth’s atmosphere) are spurting from Europa’s southern pole.
This would mean that the Europa Clipper — a concept space probe that Nasa has been developing for just such a mission — could conceivably fly through these plumes of water vapour, collecting samples from Europa’s interior without having to face the cost and difficulty of landing on the surface.
Although the 2015 proposed budget is the first time funding to study Europa has been explicitly requested, Nasa has has stressed that all of this work is extremely preliminary.
Europa is a very challenging mission operating in a really high radiation environment, and there’s lots to do to prepare for it,” Nasa’s chief financial officer Beth Robinson said to reporters on Tuesday. “We’re looking for a launch some time in the mid-2020s.”
And while the $15 million set aside for research on a Europa mission is tiny compared to the total budget, space enthusiasts should not be downhearted – more than of the proposed budget was allocated for “human exploration operations”, aka getting humans off the planet.
Nasa is currently working on a new crew vehicle (the Orion spacecraft) as well a heavy-lifting rocket designed “to take astronauts farther into the solar system than we have ever gone before.”
Both of these crafts will be instrumental in the space agency’s plans to send astronauts to an asteroid by 2025 and to Mars some time in the 2030s. So even if we don’t find extraterrestrial life elsewhere in the Solar System, it seems we would at least have escaped the boundaries of our own planet.