R136a1 - The Potential Earthwhacker
Posted: Tue Nov 24, 2015 5:21 am
https://en.wikipedia.org/wiki/R136a1[/url] Rotation[edit]The rotation rate of R136a1 cannot be measured directly since the photosphere is hidden by the dense stellar wind and the photospheric absorption lines used to measure rotational doppler broadening are not present in the spectrum. A NV emission line at 2.1 µm is produced relatively deep in the wind and can be used to estimate rotation. In R136a1 it has a FWHM of about 15Å, indicating a slow or non rotating star, although it could be aligned with its pole facing Earth. R136a2 and a3 are rotating rapidly and the closest evolutionary models for R136a1 match a star still rotating with an equatorial speed of ∼200 km/s−1 after ∼1.75 Myr.[5] A type Ic supernova can produce a GRB if the star is rotating and has an appropriate mass. R136a1 is expected to lose almost all its spin long before core collapse so a GRB is unlikely.[34] Seems a contradiction in itself? So lets assume it does rotate, but it is not apparent because its GRB earthwhacker crosshair, aka its pole, is aimed towards us. So if that thing GRB's, then we're fucked I guess. (don't take my post here too serious, but on the other hand, its a GRB, maybe we should...
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