# How long would it take light from the sun to reach Mercury?

Oct 14, 2016

From perihelion to aphelion, it ranges from 2 m 33 s to 3 m 53 s,

#### Explanation:

The orbit of Mercury is highly eccentric. The orbit eccentricity is

Light second = 299192.458 km.

From Planetary Fact Sheet, NASA,

Aphelion = 69.8 million km.

At the farthest-from-Sun, aphelion, sunlight takes.

$69.8 X {10}^{6} / 299792 s$

=233 s, nearly, to reach Mercury.

When nearest at perihelion - 46.0 million km,

the time taken is

$46 X {10}^{5} / 299792 s$

= 153 s.

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