Space

I first wrote this after a recent particularly silly story about Nibiru, published in the Daily Telegraph: The end of the world now predicted for December say doomsday groups: "Terrifying stuff. Apparently, the planet due to collide with us is often visible, you may have seen it already. If you spot a blob next to the sun when you take a photograph, it could be the deadly planet, not a reflection." It is not written entirely seriously in tone I think. Still humour is easy for some readers to miss in print, and some people take all of this very seriously. I wrote this originally as a…

In the film version of "The Martian", the main character is trapped on the red planet and is forced to figure out how to grow food. He declares he is going to "science the s--t out of" the issue before instead engaging in regular old agriculture mixed with some engineering. But science may soon help, researchers have discovered a gene that could open the door for space-based food production. Professor Peter Waterhouse, a plant geneticist at QUT, discovered the gene in the ancient Australian native tobacco plant Nicotiana benthamiana, known as Pitjuri to indigenous Aboriginals tribes,…

Science fiction stories often suggest that ETs, and our future selves also, would be expansionist, colonizing the galaxy, taking over worlds, and so forth. It's natural enough, because we are expansionist ourselves. But it's actually quite easy to see that ETs simply can't have expanding populations, at least not for very long. Not if they are anything like us.  It's a simple calculation which I covered before. If their doubling time is once a century, say (for  ease of calculation) - then in a thousand years, their population multiples by a little over a thousand (two to…

Sorry, I accidentally made two copies of this article with different titles. And both have comments, so not sure what to do. Unless you want to read the comments here, please visit the newer copy, Why ETs Won't Need to Colonize or Expand. Science fiction stories often suggest that ETs, and our future selves also, would be expansionist, colonizing the galaxy, taking over worlds, and so forth. It's natural enough, because we are expansionist ourselves. But it's actually quite easy to see that ETs simply can't have expanding populations, at least not for very long. Not if they are…

Jupiter's moon Europa is believed to possess a large salty ocean beneath its icy exterior, and that ocean, scientists say, has the potential to harbor life. Indeed, a mission recently suggested by NASA would visit the icy moon's surface to search for compounds that might be indicative of life. But where is the best place to look? New research by Caltech graduate student Patrick Fischer; Mike Brown, the Richard and Barbara Rosenberg Professor and Professor of Planetary Astronomy; and Kevin Hand, an astrobiologist and planetary scientist at JPL, suggests that it might be within the scarred,…

Scientists have predicted a new phase of superionic ice, a special form of ice that could exist on Uranus and Neptune, thanks to a computer solution performed by a team of researchers at Princeton University.  Unlike water or regular ice, in superionic ice the water molecules dissociate into charged atoms called ions, with the oxygen ions locked in a solid lattice, while the hydrogen ions move like the molecules in a liquid. The model predicts an entirely new type of superionic ice that they call the P21/c-SI phase, which occurs at pressures even higher than in the interior of giant ice…

Durable crystals called zircons are used to date some of the earliest and most dramatic cataclysms of the solar system. One is the super-duty collision that ejected material from Earth to form the moon roughly 50 million years after Earth formed. Another is the late heavy bombardment, a wave of impacts that may have created hellish surface conditions on the young Earth, about 4 billion years ago. Both events are accepted but unproven and the dates were estimated from zircons retrieved from the moon during NASA's Apollo voyages in the 1970s. A study of zircons from a gigantic meteorite impact…

Can an astronaut throw a ball to the Earth? The answer is Yes, and No. Depends what you mean by hitting the Earth. First, if you throw a ball towards the Earth - yes it's traveling that way when you throw it. So, it is natural to think that no matter how slow it is, it would get there eventually. However, we aren't used to throwing things in orbit, and our intuitions can often lead us astray. This astronaut is throwing something out of the ISS. Can it hit the Earth? Let's look at what happens half an orbit later (about 45 minutes later). The extra velocity you gave it with your throw…

Within modern cosmology, the Big Bang marks the beginning of the universe and the creation of matter, space and time about 13.8 billion years ago. Since then, the visible structures of the cosmos have developed: billions of galaxies which bind gas, dust, stars and planets with gravity and host supermassive black holes in their centres. But how could these visible structures have formed from the universe's initial conditions? To answer this question, theoretical astrophysicists carry out cosmological simulations. They transform their knowledge about the physical processes forming our universe…

The Death Star of the movie Star Wars may be fictional, but planetary destruction is real. Astronomers announced today that they have spotted a large, rocky object disintegrating in its death spiral around a distant white dwarf star. The discovery also confirms a long-standing theory behind the source of white dwarf "pollution" by metals. "This is something no human has seen before," says lead author Andrew Vanderburg of the Harvard-Smithsonian Center for Astrophysics (CfA). "We're watching a solar system get destroyed." The evidence for this unique system came from NASA's Kepler K2 mission,…