‘Space’ Archives
An Asteroid Born Near the Earth
This morning we stick with the planetary migration theme begun on Friday, when the subject was a possible ice giant that was expelled from the Solar System some 600 million years after formation. We have a lot to learn about the mechanisms that could force such ejections, but it’s becoming clear that objects up to planet size do indeed migrate, [...]
A Gas Giant Ejected from our System?
Free-floating planets — planets moving through interstellar space without stars — may not be unusual. If solar systems in their epoch of formation go through chaotic periods when the orbits of their giant planets are affected by dynamical instability, then ejecting a gas giant from the system entirely is a plausible outcome. David [...]
A Gas Giant Ejected from our System?
Free-floating planets — planets moving through interstellar space without stars — may not be unusual. If solar systems in their epoch of formation go through chaotic periods when the orbits of their giant planets are affected by dynamical instability, then ejecting a gas giant from the system entirely is a plausible outcome. David [...]
A Look at Methane-Based Life
Could life exist on a world with a methane rather than a water cycle? The nitrogen-rich atmosphere of Titan, laden with hydrocarbon smog, is a constant reminder of the question. Cassini has shown us the results of ultraviolet radiation from the Sun interacting with atmospheric methane, and we’ve had radar glimpses of lakes as well as the [...]
Pluto/Charon: A Dangerous Arrival?
We’ve often considered the effect of interstellar dust on a spacecraft moving at a substantial percentage of the speed of light. The matter becomes even more acute when we consider an interstellar probe arriving at the destination solar system. A flyby mission moving at ten percent of the speed of light is going to encounter a far more dangerous [...]
2005 YU55 Closest Approach Today
2005 YU55, an asteroid roughly the size of a city block, makes its closest pass today, approaching within 325,000 kilometers, closer than the distance between the Earth and the Moon. It will be another seventeen years before we get an asteroid as substantial as this in such proximity. That one is 2001 WN5, which will pass halfway between the Moon [...]
The Light of Alien Cities
If you’re looking for a new tactic for SETI, the search for extraterrestrial intelligence, Avi Loeb (Harvard-Smithsonian Center for Astrophysics) and Princeton’s Edwin Turner may be able to supply it. The duo are studying how we might find other civilizations by spotting the lights of their cities. It’s an exotic concept and Loeb understates [...]
Millis: Of Time and the Starship
What next for the 100 Year Starship Study? NASA and the Defense Advanced Research Projects Agency will make the call, as Tau Zero founder Marc Millis told Alan Boyle in his recent interview. To talk to Boyle, Millis donned virtual garb and appeared in Second Life in robotic form, but the interview is now available as a podcast on BlogTalkRadio and [...]
Dying Stars and their Planets
Although I can’t make the journey just then, I wish I could attend an upcoming conference at Arecibo (Puerto Rico) called Planets around Stellar Remnants. The meeting takes place twenty years after the discovery of the first exoplanets, the worlds orbiting the millisecond pulsar PSR B1257+12. I’ve been interested in the fate of planets around [...]
The Fate of Planets Near Galactic Center
It was Gregory Benford who used the wonderful phrase ‘the first hard science fiction convention’ to describe what happened at the 100 Year Starship Symposium. It was an apt choice of words. ‘Hard’ science fiction refers to SF that goes out of its way to get the science right, and in which the scientific and technical details play a [...]
