photo #6868541

Taya Keating (Member 53,065) watched this sunrise from the summit of Mount Rinjani on the island of Lombok, Indonesia. The volcano, which is the second highest in Indonesia, cast its long shadow down through the morning haze. Altocumulus clouds above, Stratocumulus beyond, and a few Cumulus clouds in the volcano’s crater all enjoyed the light show with Taya. From its shadow alone, you might suppose Mount Rinjani must rise in peak like a perfectly symmetrical cone. But it doesn’t.In fact, any mountain casting a long shadow like this tends to appear to have a symmetrical peak even when, like Rinjani, its summit is more jagged and irregular. The perfect triangle shape of the shadow is due to the effect of perspective far more than the mountain profile. When observing a shadow across the sky like this, think as if you’re looking down the length of an enormous, straight tunnel stretching off into the far distance. Like the imaginary tunnel, the shadow’s sides converge evenly due to perspective. Only the shadow’s very tip reflects the profile of the mountaintop. This part of the shadow is very small because of its distance. From where Taya stood at its summit, Rinjani’s shadow would have stretched across the sky some 200-300 miles (300-500 km).