On August 2, 1971, at the end of the last EVA of the Apollo 15 mission, Commander David Scott took a few minutes to conduct a classic science experiment in front of the TV camera that had been set up just outside the LM Falcon at the Hadley Rille landing site. Scott, a former Air Force pilot, recreated a famous demonstration often attributed to Galileo (which may or may not have actually been performed by the astronomer in Pisa in 1586) that shows how objects of different masses react the same way to gravity when dropped – that is, they fall at the same rate.
By performing the “acceleration test” in the vacuum environment of space (but where there is still an observable downward pull of gravity) the Earthly factor of air resistance is negated – especially on such a low-mass and low-density object as a falcon feather – thereby creating a more “pristine” setting for the centuries-old experiment than could ever be achieved here.
Got the Monday back-to-work blues? Upset by bad news headlines? Concerned about a potential future President Trump? Take a couple of minutes and watch this.
This video, published by The Royal Institution on YouTube in Dec. 2015 and shared again on Twitter today, features an adorable animation about spaceflight with narration taken from a lecture given by Carl Sagan in 1977.
At that time it had been five years since humans had last walked on the Moon, the first Space Shuttle flight was still three and a half years away and the Voyagers had only just passed the orbit of Mars. But Sagan’s confidence and enthusiasm about the future of space exploration and human spaceflight is as inspirational now as it was then…let us continue to remember his words and pass along his message to each new generation that looks up and wonders “what’s out there” and, more importantly, “can I go?”
“Artifacts from Earth are spinning out into the cosmos. I believe the time will come when most human cultures will be engaged in an activity you might describe as a dandelion going to seed.”
— Carl Sagan, 1977
When you look up at a full or full-ish Moon you can’t help but notice the large dark spots that mark its Earth-facing side. These form the face of what many call the “Man in the Moon” (or the body of a Moon rabbit, to others) and are individually called mare (“MAR-ay”) which is the Latin word for sea. Early astronomers thought they were bodies of water, but in reality they are solidified dark lava flows from ancient lunar impact events that occurred several billion years ago.
One of the biggest lunar seas, Mare Imbrium (see above), had for a while been thought to have been created by the impact of an asteroid or meteorite somewhere around 50 miles across, based solely on computer models.
Now, research conducted by Brown University professor Dr. Peter Schultz—a specialist in lunar and planetary impacts—indicates that the object that formed Mare Imbrium was likely more massive and of much larger size than once thought…perhaps even as big as 190 miles wide.
After nearly 5 years of traveling through space NASA’s Juno spacecraft is just a few dozen hours away from entering orbit around Jupiter, the Solar System’s largest, most massive, and most extreme planet.
“We are ready,” said Scott Bolton, principal investigator of Juno from the Southwest Research Institute (SwRI). “The science team is incredibly excited to be arriving at Jupiter. The engineers and mission controllers are performing at an Olympic level getting Juno successfully into orbit. As Juno barrels down on Jupiter, the scientists are busy looking at the amazing approach science the spacecraft has already returned to Earth. Jupiter is spectacular from afar and will be absolutely breathtaking from close up.”
Learn more about the mission and find out how to watch the long-awaited event live below:
This is an article, now updated, that I originally posted in 2009 during my first year of blogging. Since then more research has been done on the famous 1908 Tunguska Event and we even had a remarkably similar type of thing occur in February 2013 over the Chelyabinsk area, not too far from Tunguska, but even today, the 108th anniversary of the event, scientists aren’t in agreement over what it was that violently exploded over the boggy forests of Siberia—asteroid or comet.
Long the subject of debate, with various theories ranging from meteorite impact to a comet to a flying saucer’s sudden engine meltdown, there’s actually strong evidence that the 1908 “Tunguska Event” was likely caused by the explosion of a comet in the upper atmosphere.
This idea has been suggested before, and is supported by Cornell University engineering professor Michael Kelly’s study of – strangely enough – the space shuttle’s exhaust plumes and their effect on high-atmosphere cloud formation.
To those not familiar with the Tunguska Event, something exploded or impacted in the remote area of Russia on June 30, 1908, flattening the forest in an 830-square-mile area, but leaving no visible crater or other obvious sign of what caused the event. Nearby residents reported the sound of a massive explosion, but that’s about it. Whatever it was, the devastation it caused was extensive and undeniable.