How can we know the size, composition, and atmospheric makeup of distant exoplanets? NASA explains the details in this Alien Atmospheres video.
By observing periodic variations in the parent star’s brightness and color, astronomers can indirectly determine an exoplanet’s distance from its star, its size, and its mass. But to truly understand an exoplanet astronomers must study its atmosphere, and they do so by splitting apart the parent star’s light during a planetary transit.
Watch more astronomy videos, including Measuring the Universe and The Hubble Ultra Deep Field.
via Boing Boing.
As you may have heard, the asteroid 2012 DA14 silently glided past Earth on Friday, Feb. 15, 2013. Observations using radar have shown it to be an elongated rock about 20 x 40 meters (65 x 130 feet) in size…
It still didn’t get very bright; it was invisible to the naked eye. But with digital cameras and dark skies, snapping pictures of it was a matter of knowing where to aim, something photographer Colin Legg knows very well. From Perth, Australia, he captured this lovely time-lapse video of the asteroid moving past Earth right at the time of closest approach, 19:24 UTC. And he captured more than just DA14; there are some other surprises in the video, too. Make sure to set it to full-screen.
You can see DA14 sliding through the video from top to bottom on the left side of the frame. But right after the video starts, a meteor plummets through the field of view, leaving behind what’s called a persistent train—a trail of vaporized rock that can glow for several minutes.
From Slate’s Bad Astronomy.
Further Up Yonder: A Message From ISS To All Humankind by film student Giacomo Sardelli, using images and audio messages courtesy of NASA. The video’s transcript:
As the most forward deployed citizens of the planet at this moment, and the first expedition crew aboard Space Station Alpha, we are well started on our journey of exploration and discovery, building a foothold for men and women who will voyage and live in places far away from our home planet. We are opening a gateway to space for all humankind.
As we orbit the planet every 90 minutes, we see a world without borders and send our wish that all nations will work towards peace and harmony. Our world has changed dramatically, still the ISS is the physical proof that nations can work together in harmony and should promote peace and global cooperation, and rich goals that are simply out of this world.
On this night, we would like to share with all, our good fortune on this space adventure, our wonder and excitement as we gaze on the Earth’s splendor, and our strong sense that the human spirit to do, to explore, to discover has no limit.
Times are hard all over the world, but this is a time when we can all think about being together and treasuring our planet, and we have a pretty nice view of it up here.