Thursday, 6 October 2016

Superfast Spinning Stars Show Our Sun Is Special – And So Is Earth

Weird stars show how special our sun is. Image courtesy of Fred the Oyster, Creative Commons (CC BY-SA 4.0).

Joel Kontinen

Bill Nye might call himself the Science Guy, but his science is often badly outdated.

Recent research suggests his view of our sun is simply wrong. This is what he said:

I'm insignificant. ... I am just another speck of sand. And the earth really in the cosmic scheme of things is another speck. And the sun an unremarkable star. ... And the galaxy is a speck. I'm a speck on a speck orbiting a speck among other specks among still other specks in the middle of specklessness. I suck.”

New Scientist summarises the findings of a recent study that shows just how wrong Bill Nye is:

Our star is a particularly calm one. Hot, massive ‘early-type’ stars can spin almost 100 times faster than the sun, causing them to bulge in the middle. The gas around the star’s equator is then farther away from its centre, so it cools more than other parts of the star’s surface, in a phenomenon called gravity-darkening. The poles, meanwhile, remain hot and dense.”

John Ahlers, a researcher at the University of Idaho in Moscow, has examined what effect this would have on a planet orbiting such a star.

“Early-type stars emit mostly UV light, so this corresponds to yearly shifts of up to 80 per cent in the UV radiation hitting the planet. And because these planets would be directly over the star’s chilled equator twice in each orbit, it would go through two summers and two winters each year.

In extreme situations, the planet’s surface could rapidly oscillate between a boiling hellscape and a frozen tundr

The research is based on observations of the cause of seasons on the good Earth:

Earth’s seasons come from the planet’s tilt: as we orbit the sun, one hemisphere leans towards it, receiving more direct sunlight, while the other leans away.”

In contrast to what Bill Nye thinks, our sun is anything but unremarkable. Almost everything in our solar system, from Earth’s magnetic field, the Moon and the giant gas planets, appears to be fine-tuned to keep Earth habitable.

That is exactly what we would expect, as Genesis is reliable history.


Crane, Leah. 2016. Superfast spinning stars cause strangest weather in the universe New Scientist (3 October).