Brown dwarfs and so-called "nomad planets" could effectively be "rest stops" in future interstellar travel.Rutland, United Kingdom - Our galaxy, the Milky Way, is composed of billions of stars and planets, dust and gas. According to school textbooks, everything works like clockwork; stars are born from clouds of gas (known as nebulae) and the disk of gas and dust surrounding newborn stars agglomerate to build the planets.
But, like any scientific field, our understanding of the galaxy gets reshaped and modified whenever we send a new space telescope into orbit or attach new optics to a monster observatory. And last month, the well-established idea that a planet needs a star to exist was turned upside-down. What's more, by removing the necessity for a star, we may have stumbled on an interesting solution to interstellar travel.
In February, a fascinating paper was published in the Monthly Notices of the Royal Astronomical Society detailing calculations on how many "nomad planets" the Milky Way must contain after estimating our galaxy's mass from how much gravity it exerts on surrounding space. Scientists from the Kavli Institute for Particle Astrophysics and Cosmology (KIPAC) had uncovered something surprising - there are likely many more planets in the Milky Way than stars. In fact, this may not sound surprising at all; NASA's Kepler space telescope has uncovered many multi-planetary systems not too dislike our Solar System - logic dictates that if most stars have planets orbiting them, many will have multiple planets orbiting them. But Louis Strigari and his Kavli team calculated that there must be 100,000 planets for every star in the Milky Way. That's a lot of planets! Read More
