17 January 2017 | 1 °C

Lights On For The Territory

M@
By M@ Last edited 122 months ago
Lights On For The Territory
londonatnight.jpg

We were only marvelling a couple of days ago - during a night flight back from t'other side of Pond - at the hazy orange glow permeating the whole of the south east of England. But the light pollution looks even more remarkable from higher up, as this 2003 image from the International Space Station attests.

It's interesting to note that some of the most obvious features of night time London are also its oldest. Several of the straight lines radiating from the centre are of Roman origin, and the brightest pixels of all are from the ancient City area.

Ironically, the space station itself is also quite a candle. Now under resumed construction, it's the brightest object in the night sky after the moon. What would the romans have made of that?

Last Updated 14 November 2006

piersy

Are those rain drops on the lens? I hate it when that happens!!

Paul Mison

I was a bit surprised by your assertion that "the space station itself is also quite a candle. Now under resumed construction, it's the brightest object in the night sky after the moon". I looked it up, and the maximum magnitude obtained by the ISS is about -3.3, but it averages +1.5. (Magnitudes are backwards: 0 is bright, and 5 is dark. Negative magnitudes are progressively brighter.)

In contrast, for natural objects, Venus peaks at magnitude -4.4 and is at -4.1 when it's easiest to see. Currently it's at -3.8 but too close to the Sun to be easily visible. Jupiter often reaches a similar magnitude, and is currently at -1.6. (All data from Heavens Above, which will tell you when and where to look for ISS and the planets.)

However, there are brighter still objects that are man-made. The abandoned Iridium satellite phone system has left a legacy of bright flares, up to -8 in magnitude, which are indeed more visible than anything in the sky except the Moon and Sun.

For those annoyed by London's light pollution, the Campaign for Dark Skies is worth a visit.