Amusing factoid of the day

[bellinghman]

So, at the end of this month, Mars will be closer than it has been for 60,000 years.

Pretty impressive, till you discover how much closer than the previous closest distances that is.

It's 110 metres closer than two years ago,

It's 18 centimetres closer than it was in 1924. Yes, that's a mere seven inches. Less than two hands. In over 55 million kilometres.

Correction: As pointed out, that miniscule distance is a scale distance, assuming Mars is actually 528 metres away, not 100 million times further away, and the size of a tennis ball.

BBC report

Sometimes, details like this get missed.

Comments

[simonb.livejournal.com]

The critcal point here is that the distances were in relation to Mars being the size of a tennis ball!

According to this article from NASA every second brings us 10km closer to Mars.

This page shows how close Mars can come at times in AU (i.e.average distance from the Earth to the Sun, equals 93 million miles or 150 million kilometers).

[bellinghman.livejournal.com]

Oh, duh!

I missed that scale bit entirely.

In that case, the whole thing makes much more sense and is much more impressive.

[simonb.livejournal.com]

One thing to think about is that wobbles in the orbit of mars would probably bring it 110m closer to us :)

[bellinghman.livejournal.com]

That's what I thought they were calculating for.

[simonb.livejournal.com]

Slightly wobbles in orbit are different to the distances between the planets which change due to orbital speeds, positions in orbit, etc.

The other fun thing this month is that mars is going to have retrograde motion - when it appears to reverse course in the sky. See this page for details.

[bellinghman.livejournal.com]

Retrograde motion of Mars was one of the main reasons planets are so called, from the Greek for 'wanderer'. Not only does Mars go across the sky, sometimes it wanders backwards for a while.

(I wish the spell checker here understood English. Or am I missing something?)