As space travel becomes more and more refined over the years and with commercial space travel flights seemingly around the corner, more and more people are asking where in outer space is it suitable for life to exist.The most popular locations are usually planets close to a sun, possessing water and some semblance of an atmosphere. Mars, the fourth planet in the Solar System, has traditionally been the most popular location for either alien life or the possibility of human colonization in the future. However, while Mars expedition plans have been in the works for years, NASA announced plans to build a space probe to send to another location in the 2030s, according to a news.co.au report.The target for this probe, however, is one that is possibly more suitable for life than the Red Planet: Europa.Rather than a planet, Europa is one of Jupiter's moons; and despite being smaller than Earth's moon, it possesses surprising qualities that may make it one of the most suitable locations for life in outer space. The moon has a thin atmosphere; a hypothesized molten core similar to Earth's for heating; and an ice crust, giving the possibility that there are oceans underneath the ice.The idea of Europa being home to life is nothing particularly new, and has been a staple of science-fiction for many years – most notably in the book and film adaptation of 2010: Space Odyssey Two by Arthur C. Clark. However, a discovery by NASA in 2018 of water plumes supported earlier evidence of the hypothesized oceans of water beneath the ice. The announcement of the probe – called the Europa Clipper – was followed later by the European Space Agency's announcement of the development of their Jupiter Icy Moons Explorer (JUICE), slated to be sent by 2029, according to the report.These probes to Europa are a gamble, but according to some scientists, successfully finding life seems highly likely.“Discovery now seems inevitable and possibly imminent,” said University of Melbourne researcher Cathal O’Connell, according to news.co.au.“It seems inevitable other life is out there, especially considering that life appeared on Earth so soon after the planet was formed,” O’Connell continued. “And the definition of ‘habitable’ has proven to be a rather flexible concept too.“A discovery, if it came, could turn the world of biology upside down.”But not aside from biology, a discovery of extraterrestrial life – even only microscopic bacteria – would have profound religious ramifications, as the discovery of life in space could represent a "second genesis," according to O'Connell.But as difficult as getting probes to Europa and having them successfully land there, the biggest challenge is actually getting below the ice crust, which is likely as hard as granite.Drills wouldn't be enough for the job, and scientists are currently experimenting with a slew of possible methods – including lasers and even a nuclear reactor – to melt through.After that, the challenge would be going into the ocean.Europa isn't the only moon that scientists had considered a possible home to alien life, with some of Saturn's moons, specifically Titan and Enceladus, to be possible homes, due to possessing a thick atmosphere with visible large bodies of liquid and plumes of salt-water, respectively. However, Titan seems less likely, after a probe sent in 2004 determined the bodies of liquid were composed of methane, rather than water.Of course, life does exist in outer space, after Israel's Beresheet moon lander dumped thousands of microscopic tardigrades, also known as "water bears," onto the Moon.