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effect on Earth
editThe Vela pulsar supernova remnant is quite close to us. I have seen the distance stated as 800 light years and 1500 light years, and the time of explosion as 10,000 years ago (plus 800 or 1500). In any case, it is close enough to Earth to have had significant effects on our climate and ecosystems. This could be related to known climatic changes. 66.171.182.141 (talk) 02:07, 20 January 2008 (UTC)
The Vela pulsar has an estimated age of 11300 years. This means that the remnants of the supernovae first reached us around 11300 years ago. At a distance of 946 light years I would expect the effect to be minimal. And 11300 years is a bit too long ago to affect current climates. Jim77742 (talk) 04:23, 25 January 2008 (UTC)
The radiation from the blast reached us a long time ago, but the shock wave is still on its way, proceeding outward from the remnant, and getting closer. The nebula is estimated to be 100 - 250 lt yrs across, and twenty times the apparent diameter of the full moon. How soon before the shock wave reaches us? [1] [2] -- 99.231.134.90 (talk) 01:15, 24 November 2008 (UTC)
Couldn't that cause the annihilation of all life on Earth?141.156.47.30 (talk) 15:06, 31 October 2009 (UTC)
- A sphere with a radius of 1000 light years has a surface area of about 4*pi*(10^15)^2 = 10^34 square meters. The effective surface area of the Earth, i.e. the area of a disk with the radius of the Earth's, is pi*(6x10^6)^2 = 2x10^13. Thus, the Earth would catch about a fraction of 1/(2x10^21) of Vela's progenitor star's mass. Assuming a reasonable 20 solar masses this comes out to a fraction of 1/(10^20) of a solar mass. The Sun's mass is 10^30kg, which means a total of 10^10 kg = 10 million metric tons of material would hit the Earth. That's a meager 1.7 times the mass of the pyramid at Giza (according to Wolfram|Alpha)... There is absolutely no need to worry...Tjips (talk) —Preceding undated comment added 10:46, 2 January 2013 (UTC)
P: Great bit of maths Tjips :) Fig (talk) 20:54, 1 February 2020 (UTC)
Rotation period
editThe article gives a rotation period of 89.33 ms (source from 2005). Most measurements I can find, like this measurement from yesterday, give a period of 89.41 ms, and slowly decreasing. Which of these is correct? Renerpho (talk) 18:31, 24 July 2021 (UTC)