The link interprets the photo as showing the difference in economic activity between what used to be East and West Berlin, where “the more dense, commercial district on the west is lit up by bright white lights, while the eastern half of the city emits a softer, yellow glow.” It’s not clear to me whether this interpretation came from the photographer, astronaut Chris Hadfield, or not, but Don Pettit puts forth another explanation in the video Cities at Night. Starting at 6:48, Pettit says of Sao Paulo, Brazil, “the older parts of town is seen in blue-green from mercury vapor lighting and the newer boroughs are yellow-orange from sodium vapor lighting.” Although it’s true that economic development in the former East Germany has stagnated since reunification, I don’t think this photo tells us anything about current economic health. Rather, it just shows that development in the east came later than in the west.
Image description: Earth, as seen in the sky above Mars. This is the first image ever taken of Earth from the surface of a planet beyond the Moon. It was taken by the Mars Exploration Rover Spirit on March 8, 2004.
Comet 2012 S1 (ISON) is still out beyond the orbit of Jupiter, but it may shine brighter than the full moon when it is expected to pass near Earth between late 2013 and early 2014.
“If it lives up to expectations, this comet may be one of the brightest in history,” said [Raminder Singh] Samra, of the H.R. MacMillan Space Centre in Vancouver, Canada.
So what makes a comet a showstopper? A lot depends on how much gas and dust is blasted off the central core of ice and rocks. The bigger the resulting cloud and tail, the more reflective the body may be.
Because 2012 S1 appears to be fairly large—possibly approaching two miles (three kilometers) wide—and will fly very close to the sun, astronomers have calculated that the comet may shine brighter, though not bigger, than the full moon in the evening sky.
This is pretty exciting, but…
“Some comets have been notorious for creating a buzz but failing to put on a dazzling display,” he said. “Only time will tell.”
Shot from my backyard on a point & shoot through a no. 14 welder’s glass (which is safe for sun viewing but accounts for the green tint). Technical details: 6/5/12 17:08:51 (the camera’s clock isn’t set for daylight time and is about two minutes fast&mdssh;so the correct time should be around 18:06 or so, Central Daylight Time) f/8, 1/25 sec., ISO 80. Gonna go reset the camera clock and take more photos now.
How did Malley, who was clearly in awe of Armstrong during the interview, manage to land his exclusive? “I know something not a lot of people know about Neil Armstrong – his dad was an auditor,” he said.
No, this is not the supermoon. Or at least “supermoon” has no meaning here. This is a composite image (aka “fake” or “bullshit”) that depicts a physically impossible scene. You could blow this up and find Photoshop artifacts in it, but that’s unnecessary—you just need to remember that moonlight is actually reflected sunlight, and with the sun behind it, the real moon would be dark and obscured by the sky glow (it’s called “new moon”) instead of shining as it does in this image. I’m disappointed that Discovery News, a science blog, would pass this along without giving it the critical eye first.
In an attempt to illustrate the size of the universe, the BBC has put together an enormous infographic that spans 58,180 vertical pixels (equivalent to 18 letter-sized pages printed at 300 dpi). And, when you get to the bottom…you’ve only reached the end of the Solar System. The graphic estimates that you’d have to keep scrolling for 22 million years to reach the far edges of the known universe. Live long and prosper, friends.
Specifically, that’s with your arm fully extended. Put your fist right in front of your eyes and you’ll block out the entire sky.
Anyway, this reminds me of a few handy (literally) guides for measuring angular distances across the sky: with your arm extended, the width of your little finger measures about 1° across, your fist is about 10° across, and the tip-to-tip span of a spread-out hand, from thumb to little finger, is about 25°. “But not everybody has the same size hands,” you say. Yes, of course that’s true, but people with smaller hands also have shorter arms (and vice versa), so it all works out the same.
Compiled from a series of images taken by a geosynchronous satellite*, this NASA video shows the illuminated half of the Earth shift as the Sun moves up and down relative to its axis. At the equinoxes, the light comes strictly from the right side of the image, while in the northern summer the light source appears to come from the upper-right and during winter it shifts to the lower-right. In reality, of course, the Sun stays stationary and it’s the Earth that moves in orbit, and its tilted axis causes different parts of the planet to receive more sunlight during different parts of the year, which we experience on the ground as the seasons.
* You can tell that it hovers above the same spot on Earth by noticing that North Africa and the Arabian Peninsula, which are exposed by their lack of cloud cover, stay in the same place on the upper-right portion of the images through the video.