M1 in slow motion (Lorenzo Siciliano)

Celestial hemisphere: Northern · Constellation: Taurus (Tau) · Contains: Crab nebula · M 1 · NGC 1952

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M1 in slow motion

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M1 in slow motion

Hi all.

After the colourful M1 posted a few days ago, now the going gets tough.

I did some shots at M1 in the late 2009, so I was thinking: and if...

And I got it!

Here is an animation of the two shots: the first taken in 2009 and the second in 2015.

Well, the nebula clearly expands!!!

In a mere six years apart, its expansion is clearly obvious!

But this was not enough.

I grabbed my pocket calculator and did some little math.

From my images, the nebula expands at a rate of 0.197 arcsec/year.

Given its estimated distance of 2000 parsec and doing some calculation, I estimate that gases expand at a velocity of about 1850 km/s, only a 20% more than the "official" rate of expansion of 1500 km/s and well within the uncertainties of calculations!

Interesting, isn't it?

Enjoy!

Lorenzo

Imagers of Italy

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M1 in slow motion

M1 in slow motion

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