Earth is less of a backwater than we thought, say astronomers
The galactic spiral arm where our solar system resides may be a big deal after all, according to a new analysis.
Robert Hurt, IPAC; Bill Saxton, NRAO/AUI/NSF
Astronomers seem to delight in reminding us of our unimportance. Our planet, they're constantly telling us, is a backwater, a tiny speck circling an ordinary star on the boring periphery of a middling galaxy.
The astronomer Carl Sagan was the undisputed master of taking us down billions and billions of notches. Here he is in his 1980 book, Cosmos, doing his very best to make us feel completely insignificant:
"For as long as there been humans we have searched for our place in the cosmos. Where are we? Who are we? We find that we live on an insignificant planet of a humdrum star lost in a galaxy tucked away in some forgotten corner of a universe in which there are far more galaxies than people."
For those of you whose self-esteem is linked to your proximity to the center of the universe, this is depressing stuff. We're living, it seems, in the cosmic equivalent of flyover country.
Or maybe not. New research shows that our planet might not be quite the provincial, iceberg-lettuce-eating exurbia that astronomers once thought. A new suggests that our galactic neighborhood is actually a pretty vibrant place.
We reside on a spiral arm of the Milky Way known as the Local Arm, which sits between two big spiral arms called the Sagittarius Arm and the Perseus Arm. Previously, astronomers regarded our Local Arm as a minor spur, a barely noticeable nubbin of stars dangling between its two majestic neighbors. But now it seems that the Local Arm is a big deal in its own right.
"Our new evidence suggests that the Local Arm should appear as a prominent feature of the Milky Way," said Alberto Sanna, of the Max-Planck Institute for Radio Astronomy, in a press release. Sanna and his colleagues presented their findings to the American Astronomical Society's meeting in Indianapolis this week, and details of their findings are published in the Astrophysical Journal.