Our galaxy may be awash in homeless planets, wandering through space instead of orbiting a star.
In fact, there may be 100,000 times more “nomad planets” in the Milky Way than stars, according to a new study by researchers at the Kavli Institute for Particle Astrophysics and Cosmology (KIPAC), a joint institute of Stanford University and the SLAC National Accelerator Laboratory.
If observations confirm the estimate, this new class of celestial objects will affect current theories of planet formation and could change our understanding of the origin and abundance of life.
“If any of these nomad planets are big enough to have a thick atmosphere, they could have trapped enough heat for bacterial life to exist,” said Louis Strigari, leader of the team that reported the result in a paper submitted to theMonthly Notices of the Royal Astronomical Society.Although nomad planets don’t bask in the warmth of a star, they may generate heat through internal radioactive decay and tectonic activity.
A set of recent papers, many of which draw on data from NASA’s Cassini spacecraft, reveal new details in the emerging picture of how Saturn’s moon Titan shifts with the seasons and even throughout the day. The papers, published in the journal Planetary and Space Science in a special issue titled “Titan through Time”, show how this largest moon of Saturn is a cousin – though a very peculiar cousin – of Earth.
“As a whole, these papers give us some new pieces in the jigsaw puzzle that is Titan,” said Conor Nixon, a Cassini team scientist at the NASA Goddard Space Flight Center, Greenbelt, Md., who co-edited the special issue with Ralph Lorenz, a Cassini team scientist based at the Johns Hopkins University Applied Physics Laboratory, Laurel, Md. “They show us in detail how Titan’s atmosphere and surface behave like Earth’s – with clouds, rainfall, river valleys and lakes. They show us that the seasons change, too, on Titan, although in unexpected ways.”
A paper led by Stephane Le Mouelic, a Cassini team associate at the French National Center for Scientific Research (CNRS) at the University of Nantes, highlights the kind of seasonal changes that occur at Titan with a set of the best looks yet at the vast north polar cloud.
This is from Journey to the Stars astronomy blog – check it out, it’s got a lot of great info :)
A spectacularly bright object recently spotted in one of the Milky Way’s neighbouring galaxies is the result of a “normal” stellar black hole, astronomers have found.
An international team of scientists, led by Dr Matt Middleton, of Durham University, analysed the Ultraluminous X-ray Source (ULX), which was originally discovered in the Andromeda galaxy by NASA’s Chandra x-ray observatory. They publish their results in the journals Monthly Notices of the Royal Astronomical Society and Astronomy and Astrophysics.
Many ULXs are too far away for astronomers to study, but the relatively close proximity of Andromeda to the Milky Way – around 2.5 million light years – gave the team opportunity to study the phenomenon.
The researchers say their study could begin to answer the question about what causes ULXs. Some scientists believe they are caused by relatively small black holes, a few times the mass of our Sun. These black holes rapidly pull in gas and dust which forms an “accretion disc” and heats up causing the material to emit X-rays.
Astronomers using data from NASA’s Spitzer Space Telescope have, for the first time, discovered buckyballs in a solid form in space. Prior to this discovery, the microscopic carbon spheres had been found only in gas form in the cosmos.
Formally named buckministerfullerene, buckyballs are named after their resemblance to the late architect Buckminster Fuller’s geodesic domes. They are made up of 60 carbon atoms arranged into a hollow sphere, like a soccer ball. Their unusual structure makes them ideal candidates for electrical and chemical applications on Earth, including superconducting materials, medicines, water purification and armor.
In the latest discovery, scientists using Spitzer detected tiny specks of matter, or particles, consisting of stacked buckyballs. They found the particles around a pair of stars called “XX Ophiuchi,” 6,500 light-years from Earth, and detected enough to fill the equivalent in volume to 10,000 Mount Everests.