Science

Science.

Voyager and the speed limit

As often happens, an IRC channel veered off-topic and onto an interesting one instead. We got to talking about clocks and frames of reference and while we were chatting back and forth someone claimed that we hadn’t made anything that had reached relativistic speed yet (or, at least nothing on the scale of the questions you get on your average physics exam about the spacecraft doing 0.9c). That may be true, but that had me wondering just how fast the fastest thing was.

That would be Voyager 1, launched 5 September 1977. It’s now about 15.9 billion km out, and is booking along at about 17 km/s which is 0.000056c. That’s pretty fast! Still going to take a while to get to the next stop, though.


Image Credit: NASA/Walt Feimer.

Finding the speed number led me to a JPL page on the NASA site about the Voyager missions. Quite interesting reading, especially about the choice of trajectories they had which allowed them to have Voyager 2 reach not just Jupiter and Saturn but also Uranus and Neptune in “12 years rather than 30″.

http://voyager.jpl.nasa.gov/news/factsheet.html

AfC

Save Pluto!

On August 24, 2006, astronomers at the International Astronomical Union General Assembly in Prague declared that Pluto is no longer a planet.

This is terrible! How can this cute fellow possibly be demoted from planet status?

Pluto, Mickey's faithful companion

There is a petition to force the IAU to reconsider. Important reasons cited as to why Pluto should be restored to full planetary status include:

The tiniest planet is beloved by kids, who are themselves tiny.

and:

Adults like Pluto, too. It rounds out the Solar System with the wonderfully-odd number Nine.

There’s also some technical babble about “gravity” and “cleaning up the neighbourhood” and such, but what further justification could you need? Sign the petition! Save Pluto!

AfC