Changing colour time-lapse from VISTA

This time-lapse video shows a series of images from the VISTA infrared survey telescope at ESO's Paranal Observatory showing the galaxy NGC 4993 in August 2017. The explosion of a kilonova in this galaxy was accompanied by the emission of both gravitational waves and gamma rays. The object was initially blue but then became much redder before fading.

Credit:
ESO/N.R. Tanvir, A.J. Levan and the VIN-ROUGE collaboration

[ametistSCUT]

This is a one-of-a-kind astronomical event - only 4 comments though. So sad!
But I'm still so happy to be able to witness it!
Thank you from the bottom of my heart to all the smart people involved in bringing this to my own eyes ❤❤❤🙏

[stokesseegers]

It turns red then dies out. Stars that are extremely far away appear as faint red dots. Because that Red Spectrum is the only thing that reaches us. This looks more like whatever cloud is around that big bright star this slowly blocking more light from the smaller one causing it to turn red and then fade out. Or the little star is moving away from us

[burakuda]

why does the colour change from blue to red??? thx