Remembering Challenger

January 28th marked the 25th anniversary of the Space Shuttle Challenger disaster, when one of the rocket boosters separated from the external fuel tank after liftoff and aerodynamic forces tore the shuttle apart. Like millions of Americans, Ethan Siegel and Greg Laden watched the orbiter disintegrate live on TV. Ethan writes that while “we found and fixed the flaws that caused the accident, and returned to space 32 months later with the Space Shuttle Discovery,” we “lost our eagerness for human space exploration in a way that would have been unfathomable 20 years prior.” NASA shifted its priorities from manned spaceflight to scientific investigation, and we have since learned a lot from the likes of Hubble, the Mars rovers, and Cassini. But still we are called to new horizons. In honor of all the trailblazers who have lost their lives in the spirit of human exploration, we pause to remember.

Advertisements

Sirius History & the Future of NASA

i-3c2c9451242aea5eb047e339dec192ca-rocketbuzz.jpgOn Starts With A Bang, Ethan Siegel presents us with an interstellar mystery. As the single brightest star in the sky, Sirius has been well-known since ancient times. But while Sirius is unmistakably blue, several historical records describe Sirius as red. Two thousand years is not enough time for a normal star to change color, so what could have happened? Simple human error? Changing atmospheric conditions? A roving Bok Globule? Or does Sirius’s companion dwarf star suggest an even more incredible explanation? In a separate post, Ethan says he won’t miss NASA’s Constellation program, a Bush-era plan to establish “an extended human presence on the Moon.” Ethan writes that returning to the moon “has no clear scientific merits,” and funding should go to more awe-inspiring pursuits such as “landing humans on other planets,” or “perhaps even reaching for another star system.” Meanwhile Matt Springer on Built on Facts finds that Constellation’s cancellation leaves NASA’s glass half-empty, with nowhere to go but down. Matt warns that NASA may soon be “strangled to death in bureaucracy,” stripped of “the inspiration that keeps the agency in the public eye.”

Links below the fold.
Continue reading “Sirius History & the Future of NASA”

Round and Round

i-0ef7c9868028a5449c5288bb5d2cbe42-solbuzz.jpgYesterday was the winter solstice, meaning the sun concluded its six-month southward course and seemed to “stand still” before beginning its journey north. Of course, this being a heliocentric neighborhood, the tilt, orbit, and rotation of Earth are what really move the sun through the sky. But don’t let that stop you from appreciating colorful crayon diagrams of the ancient “two-sphere” model of the heavens with Dr. Free-Ride on Adventure in Ethics and Science. If that’s not a useful enough approximation, you can get a modern understanding of solstices and seasonal dynamics from Anne Jefferson on Highly Allochthonous. Also on Highly Allochthonous, Chris Rowan reveals a snapshot of Saturn’s mysterious moon Titan, whose northern hemisphere is just emerging from a fifteen year winter. With middling gravity, apparent lakes and plenty of atmosphere, Titan presents a compelling prospect for extraterrestrial life, although it only receives a fraction of the sunlight we enjoy here on Earth. Finally, visit Ethan Siegel on Starts With A Bang! for a satellite view of the recent snowfall that blanketed the northeastern United States.

Links below the fold.
Continue reading “Round and Round”

Star Light, Star Bright…

i-b2b7f90a2f2d0e437ed36de5c9e0891e-starbuzz.jpgOn Aardvarchaeology, Martin Rundkvist tells us that the Geminid meteor shower is peaking tonight, so if you’ve got any wishes on the back burner, now’s your chance to make them. Of course these shooting “stars” are really bits of extinct comet 3200 Phaethon’s “sandy exhaust trail” burning up in the atmosphere—if you prefer some main sequence hydrogen-fusing affairs, head over to Greg Laden’s Blog to learn about Alcor and Mizar. This binary star system in the constellation Ursa Major has been known since antiquity, but—surprise!—Mizar is actually four stars, and Alcor is now known to be two, meaning that there are a total of six stars linked together in an “orgy of gravitational interaction.” If that’s still not big enough for you, revisit the galactic potpourri of Hubble’s Ultra Deep Field on Starts With A Bang!, where Ethan Siegel explains the optical implications of imaging from infrared wavelengths. And in another post, Siegel recommends we get our hands dirty at Galaxy Zoo, a website where anyone can help astronomers classify galactic collisions by matching up real images from a telescope to computer simulations.

Links below the fold.
Continue reading “Star Light, Star Bright…”

Water, Water Everywhere?

i-45d7ed3212056a6dd4ec3fa4da224b2e-moonbuzz.jpgOn Friday, NASA scientists confirmed the discovery of water on the moon. Using spectral analysis to determine the composition of the plume resulting from last month’s LCROSS rocket collision, they found more than 100 liters of water. Steinn Sigurðsson on Dynamics of Cats calls the presence of water on the moon “amazing,” but cautions that at these concentrations, it’s “dry by Earth standards.” Razib Khan on Gene Expression considers the implications of water on the moon: “Since humans are mostly water by weight, this is very important when assessing the practical difficulties of colonization or settlement.” In other NASA news, Greg Laden reports on his blog that after idling on the precipice of a Martian dust bowl since April 23, while engineers on Earth assessed the best way to make a break for it, the long-lived Spirit rover will risk movement again tomorrow, in a bid to continue its incredibly successful mission.

Links below the fold.
Continue reading “Water, Water Everywhere?”

Out of Sight

i-b8047228588ef795da385f34ec6b4d97-sightbuzz.jpgIn Ethan Siegel’s ongoing treatment of dark energy on Starts With A Bang!, he considers a number of alternative explanations for the dimming of redshifted supernovae. Could photon-axion oscillations be to blame, or does a “grey dust” pervade our universe? In another post, Siegel appreciates that our galaxy smells like raspberries and rum, and not, for example, Uranus. His diss to Andromedans: “I bet you stink compared to us!” For more things unseen, Greg Laden on Collective Imagination points us to Kameraflage, a technology that writes secret messages and draw pictures only visible to a digital camera. Finally, open your eyes for a stellar image of our galactic center on Dynamics of Cats, courtesy of Steinn Sigurðsson.

Links below the fold.
Continue reading “Out of Sight”