Antimatter Storms and the Universe's Dark Ages
This month on Naked Astronomy, we discover the streams of antimatter coming from lightning on Earth, and find out how to study the stars that ended the dark ages and brought light to the universe. We hear about Jupiter's role in Earth asteroid impacts, Cassini's flypast of Saturn's moon Rhea and the first science results from the Planck mission. Plus, your questions on light speed route planning, outrunning sunset and why the solstice doesn't coincide with the earliest dawn!
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The Sloan Digital Sky Survey-III has released some incredible images of the night sky, and announced plans to image even more. Now, the first catalogues of spectroscopy results have been released online, allowing anyone to access this enormous collection of data...
Does Jupiter protect Earth from asteroid impact? A new study evaluates the myth that the giant planet acts as our protector, gravitationally slinging asteroids out of a collision course...
NASA's Cassini spacecraft has completed an extremely close flyby of Saturn's moon Rhea, returning incredible pictures that allow us an unprecidented view of the surface features - including faults reminiscent of Enceladus' "Tiger Stripes"...
This month, researchers working on the Planck project released their first science data - including new galaxy clusters and clouds of cold gas in the Milky Way. Plus, they announcea greater than expected data loss rate from cosmic rays - helping to plan future missions...
Red Dwarf stars seem to be far more active than previously thought - good news for astronomers, but terrible news for any habitable planets around them...
Data from the Solar and Heliospheric Observatory, or SOHO, has been used by amateur astronomers worldwide to spot comets. Over half of all known comets have been spotted in this way, and now a student in Poland has spotted SOHO's 2000th comet!
All you need to know about relativity...
26:12 - How fast does gravity propagate?
Does Gravity propagate instantaneously? In other words, to use a fancy analogy: I move the sun 10,000,000 km in 1 sec in 1 direction, will the earth move instantaneously or will the effect only propagate at light speed to reach the earth 8 mins later?
My feeling is that the e...
29:46 - Is it possible to plot a clear course when travelling at light speed?
If we were to develop a spacecraft to travel at very high speed or near the speed of light (time travel) through space; wouldn't even a tiny grain of rice pose a serious danger? Is it possible to avoid all drifting space debris at this speed?
Thank you for your time
Gamma ray flashes seemingly coming from thunderstorms have been a mystery since first being identified in 1994. Now, using the Gamma Ray Burst Monitor on the Fermi satellite, researchers have identified the cause as beams of antimatter streaming out into space...
37:29 - Why doesn't solar wind move dust on the moon?
I know the moon doesn't have an atmosphere therefore the dust doesn't move, but if the solar wind is strong enough to remove an atmosphere from a planet, why doesn't it move the dust on the moon???
Keep up the great podcasts!
40:20 - Why doesn't the solstice coincide with the earliest dawn?
Using the Southern Hemisphere as example, on or about 22 December (Summer Solstice), the Sun is overhead at its furthest point South (Tropic of Capricorn), causing the longest hours of daylight, for all places South of that Tropic, (and of course, the shortest for all places Nort...
The first stars ended the dark ages of the universe pouring heat, light and heavier elements into an otherwise cold, dark expanse. New research uses light from quasars to analyse the clouds left behind when some of these first stars exploded...
49:43 - Does Hawking radiation selectively emit matter, rather than antimatter?
So here lies my first problem; I could see that if the anti particle got sucked in it would annihilate releasing energy (although I'm not sure where this energy would go?) and the black hole would get smaller, and the mass of the radiation would be equal to the reduction in mass ...
54:32 - How fast would you have to run to outrun the sunset on the lunar surface?
In Futurama episode 2, Fry and Leela outrun the sunset on the moon by
hopping along ...
How fast would you have to run to outrun the sunset on the lunar surface?