New measurements of the Milky Way show that our galaxy is rotating 160,000 km per hour faster than previously thought, says the US National Radio Astronomy Observatory. And we thought we were going at 800,000 km per hour already.
Researchers used highly accurate observations of radio bright points to see how quickly these points were moving. “These measurements use the traditional surveyor’s method of triangulation and do not depend on any assumptions based on other properties, such as brightness, unlike earlier studies,” says Karl Menten of the Max Planck Institute for Radio Astronomy in Germany.
If we’re going that much faster the galaxy must also be heavier, otherwise there wouldn’t be enough gravitational pull to keep hold of the Sun (NY Times). This means our galaxy is as big as neighbouring Andromeda, leading to lots of bragging in the media.
“No longer will we think of the Milky Way as the little sister of the Andromeda Galaxy in our Local Group family,” says Mark Reid, of the Harvard-Smithsonian Center for Astrophysics (press release).
So to people in Andromeda reading this in about 2 million years on the transmissions leaking from Earth, as AP says, “Take that, Andromeda!”
But wait! There’s a downside to this, as the press release notes…
The larger mass, in turn, means a greater gravitational pull that increases the likelihood of collisions with the Andromeda galaxy or smaller nearby galaxies.
Or, in the in-no-way-sensationalist headlines of the UK press:
The Daily Mail has words of reassurance for us (a development that may surprise observers of the UK media): “However, people shouldn’t be worried about the event happening any time soon – as any collision would still be at least two to three billion years from now.”
See you soon Andromeda, and if there are any more size revisions, we’ll be the ones waving the ‘our galaxy is bigger than yours’ sign.