Astronomers are anticipating the appearance of a “new star” triggered by an explosive event that could appear in the night sky anytime between now and September.
Astronomers are expecting a “new star” to appear in the night sky anytime between now and September in a celestial event that has been years in the making, according to NASA.
I mean, no. It hasn’t been years in the making, it happened a very, very long time ago. We just don’t get to see it until now.
It’s more that we’ve been anticipating the event for years.
This is saying good morning to everyone at midnight levels of pedantic. Astronomers need a common reference frame for discussing timing, and the reference frame they use is "when it's observed at Earth".
Because nothing else allows for coherent organization, discussion, or education.
A nuclear fusion event occurred in the accretion disk of a stellar remnant 2600 years ago or so. An astronomical event known as a nova will occur in the sky sometime this summer.
Discussing astronomical events would be incredibly tedious if we had to qualify everything by how many light years away / how long ago the light we’re measuring was created.
Put another way - everyone already knows we’re looking at the past, it’s like saying the sky is blue.
This has always confused me, but reference frames makes conceptual sense to me.
Even still, I like to think about how long ago what I'm seeing now actually occurred.
For example when we see a planet in our solar system in the sky we know it's still technically in the past, but it's still in timescales humans can relate to.
This binary system, T. Coronae Borealis, is 2500 light years away. That means the event we're about to witness actually occurred 2500 years ago, and the light that it emitted is just about to reach our solar system.