Space is pretty big

According to NASA, the Voyager space probe is “hurtling towards the edge of our solar system” at around 38 000 miles per hour. ‘Hurtling’ is a subjective term when you consider the distances involved, but it’s faster than land craft so we’ll let them off.

Just yesterday, Voyager sent back data implying that there is no outward motion of solar wind from its current location. Which in layman’s terms means it’s pretty close to the edge of the sun’s influence and will soon be battling with interstellar winds between stars.

It’s a long way from home, but that doesn’t mean much to you or me; after all, the corner shop is a long way from home when it’s raining. So I’m going to try and put this stuff in perspective:

• Voyager 1 has 68KB of main memory. My desktop machine has 4GB — about 61 000 times as much storage capacity
• The probe has been travelling since 1977 — that’s 33 years to date — and has covered over 10 billion miles, without hitting anything else
• Telemetry information travels back from the probe at the speed of light so it currently takes 16 hours to reach us — and 16 hours to send uplink commands back to it. Thus the probe is 16 light hours from Earth
• The probe travels at 10.5 miles per second so it travels roughly 331 million miles in one earth year
• Light travels nearly 6 trillion miles in one earth year
• So in order to travel one single light year away from earth, Voyager 1 will take… *deep breath* 17 714 earth years. Less the 33 it’s been going so far leaves us with 17 681 years
• And that’s still less than a quarter of the way to Alpha Centauri — our nearest star. To reach that, the probe would have to travel for a staggering 77 322 earth years. Adding that to our current year, 2010, means that — assuming it’s going in the right direction — the probe would reach Alpha Centauri in the year 79332
• Worse, the limitations of the speed of light mean that it’ll take over 4 years for the information of Voyager 1’s arrival to reach us, and a further 4 years for us to tell it to pull up :-)

^{Makes you feel kinda small, doesn’t it?}