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North Star May Be Wasting Away
sciencehabit writes "The North Star, a celestial beacon to navigators for centuries, may be slowly shrinking, according to a new analysis of more than 160 years of observations. The data suggest that the familiar fixture in the northern sky is shedding an Earth's mass worth of gas each year."
The Earth precesses once ever 26000 years. In 13000 years north will be pointed towards Vega.
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It's probably losing all that mass due to heat from friction. It must be under tremendous pressure, seeing as how the entire night sky pivots on that single point. Long-term this will have huge consequences - when the North Star finally wears through completely the entire universe will ricochet off into nothingness like a spinning top.
When you have nothing left to burn you must set yourself on fire
Vega is a fucking space ghetto. I don't want to point to that part of the celestial neighborhood.
You're right
Karma whoring:
"...Gamma Cephei (also known as Alrai, situated 45 light-years away) will become closer to the northern celestial pole than Polaris around AD 3000. Iota Cephei will become the pole star some time around AD 5200.
First-magnitude Deneb will be within 5 of the North Pole in AD 10000.
The brilliant Vega in the constellation Lyra is often touted as the best North Star (it fulfilled that role around 12000 BC and will do so again around the year AD 14000). However, it never comes closer than 5 to the pole.
When Polaris becomes the North Star again around 27800 AD, due to its proper motion it then will be farther away from the pole than it is now, while in 23600 BC it came closer to the pole.
In 3000 BC the faint star Thuban in the constellation Draco was the North Star. At magnitude 3.67 (fourth magnitude) it is only one-fifth as bright as Polaris, and today it is invisible in light-polluted urban skies..."
-Wikipedia
A solar mass is over 300,000 Earths, and Polaris is atleast 7 solar masses, adjusting for the most conservative of all estimates. It's apparent magnitude is about 1.9, while the magnitude of drop off (nolonger visible to the human eye) is defined at 7 (with 6 being relatively hard except under good conditions).
Setting aside the nuclear chemistry that will occur in the meantime (which tends to increase brightness), that Polaris is, in fact, multiple stars and the overall reduction of radiative and mass pressure that will be reducing the production/consumption rate*, I would posit even losing half of its mass, it would likely still be visible in 2000 years, which means the Northern Star will have since switched to Gamma Cephei.
So, no big loss here. Personally, I, for one, welcome our new Alrainian OverStar.
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*You know what, I'm actually going to do these in the coming weeks. This is sound like a fun problem, even though I do a lot more in theoretical particle physics than cosmology.
"Yeah...it was the numbers that were irrational, not the murderous cult of vegetarians...." -- Hippasus of Metapontum