When it comes to galaxies, gravity and Newton’s first law of motion often combine to put the finest earthbound sculptors to shame. Take the galaxies NGC 2936 and NGC 2937, for instance. Here we see an everyday spiral galaxy bent and molded by the gravitational influence of a featureless elliptical companion galaxy into a graceful arc of stars and gas and dust a hundred thousand light years long. Together, the two bear a remarkable resemblance to a mother penguin holding watch over a shimmering egg. It’s one of the most beautiful galaxy pairs in the heavens [Read more…] about Dancing GalaxiesShare This:
Science of Astronomy
Articles about the science of astronomy and objects that are visible in the night sky.
Is the Universe Too Dangerous for Life?
It’s a question that inevitably arises in conversations about the cosmos: does life exist elsewhere in the universe?
For those who hope the answer is “yes”, the harvest of exoplanets by NASA’s Kepler Space Telescope and other telescopes over the past decade has been hugely encouraging. As of mid 2019, in the small slice of sky under its exacting gaze, analysis of Kepler’s measurements found more than two thousand extrasolar planets, and all telescopes have confirmed some 3,700 exoplanets. Extrapolating these results, astronomers estimate our Milky Way galaxy alone might hold some 10 billion planets that may have the temperature and composition to harbor habitable life. With that much real estate, many believe that complex or even intelligent life must have formed on at least some of these? [Read more…] about Is the Universe Too Dangerous for Life?Share This:
We normally cover really big things in these pages, things like planets, stars and galaxies. But the cosmos is ultimately built from very small bits and pieces that organize themselves on a tiny scale that are at least as beautiful as anything to be seen in the night sky. This video, created by Beauty of Science, shows at an accelerated pace the formation of six kinds of crystals out of solution. Whereas many astronomical objects coalesce because of gravity, these crystals are made from a beautiful interplay of electric forces, geometry, and quantum mechanics. Quite a beautiful sight!Share This:
Barnard’s Star Has a Planet After All
It was a discovery nearly a century in the making, but astronomers have finally detected a planet around the speedy little red dwarf known as Barnard’s Star. The existence of the planet is not particularly surprising given the vast harvest of exoplanets discovered since 1995 around all manner of stars. Nor is the planet a habitable world, to be sure. But it was welcome news nonetheless to find that the nearest single star to Earth has at least one planet in its relatively feeble gravitational embrace.
In many ways, Barnard’s Star was the “white whale” of exoplanet hunters. That’s because the star is close, just six light years away, the second-closest star system to Earth, which should make it easier to find an orbiting planet. And the star is prominent because of its speedy apparent motion across the sky. Barnard’s Star is also old, more than twice the age of our own solar system, so it’s had plenty of time to form a planetary system. But for nearly a hundred years, astronomers have examined the star for evidence of a planetary system using visual observation, photographic imaging, and finally using modern spectroscopic planet-hunting techniques. They came up empty every time [Read more…] about Barnard’s Star Has a Planet After AllShare This:
Algol, the “Demon Star”
Algol, the second brightest star in the northern constellation Perseus, is the finest example of an eclipsing variable star in the entire sky. In this compact stellar system, two stars revolve around their common center of mass in a rhythmic and precise gravitational dance, and the resulting eclipse causes the brightness of the star to vary like clockwork to a degree that’s easily perceptible to the human eye. And you can watch it from your backyard. No telescope required [Read more…] about Algol, the “Demon Star”Share This: