Redshift and eclipse
I am thoroughly dispirited. I had wanted to write today about how it is fascinating that we have validated Einstein’s theory of general relativity for the first time in an extreme environment: in the neighbourhood of a black hole. The test involved the detection of an effect called the gravitational redshift, whereby light that is moving from a region of higher to lower gravitational potential appears redshifted. In other words, light seen moving from an area of stronger gravitational field to an area of weaker gravitational field appears to be redder than it actually is, if the observer is sufficiently far from the source of this field. The observation of this redshift is doubly fascinating because it is also an observation of time dilation in action.
The European Southern Observatory’s Very Large Telescope (VLT) took the initiative 26 years to make this check; it was completed and announced yesterday, July 25. The source of the gravitational potential was the black hole at the Milky Way’s centre, called Sagittarius A*, and the source of starlight, a stellar body known only as S2. Triply fascinating is the fact that the VLT observed S2 swinging by Sgr A* at a searing 25 million km/hr. Phew!
But through this all, I am distressed because of an article I spotted a few minutes ago on NDTV’s website, about how we must not eat certain foods during a lunar eclipse – given the one set to happen tomorrow – because they could harm us. I thought we had been able to go a full day without a mainstream publication spreading pseudoscientific information about the eclipse, but here we are. I weep for many reasons; right now, I weep most of all not for the multitude of quacks we inhabit this country with but for Yash Pal. And I wish that, like S2, I can escape this nonsense at 3% of the speed of light when it becomes too much.