POSTED by: Scott McKittrick on 10/13/2009
Tempel 1 on Impact via
Nasa In late 2006, a Nasa probe, called Deep Impact, collided with the Tempel 1 comet. The resulting outgassing lasted for 13 days and released between 33 and 66 million pounds of matter.
The Deep Impact mission was instituted to learn more about the chemical makeup of comets. The spacecraft was made up of two parts, the flyby section and the impactor. The impactor hit the comet with the same force as an explosion of five tons of dynamite. The flyby section then flew through the plume of debris and collected data about it. The data was later radioed back to earth for analysis. The impactor also had a camera and recorded images until about 3 seconds before impact.
More Info
See the Introductory Post
See other Daily Curiosities Posts
POSTED by: Scott McKittrick on 10/09/2009
…On the Moon. At the end of the Apollo 15 mission, immediately prior to returning to their spacecraft, astronauts David Scott and James Irwin performed a short experiment to prove that Galileo Galilei was correct in his theory that objects in a vacuum fall at the same rate regardless of their mass.
The experiment involved dropping a geology hammer and a falcon feather at the same time and seeing which one hit the surface first. On earth the hammer will always hit the ground first, but on the moon, where the atmosphere is all but nonexistent, both hit the ground at the same time. The actual cause for the disparity on earth is air resistance, not a difference in mass. Linked is a video of the experiment taken from the surface of the moon.
More Info
See the Introductory Post
See other Daily Curiosities Posts
POSTED by: Scott McKittrick on 10/08/2009
Early on the morning of June 30th, 1908, a huge explosion rocked the Siberian forest. The explosion was so strong that it felled trees in a 850 square mile area around the blast site.
100 years later the cause of the explosion is still a mystery. The prevailing theory states that a meteorite or comet about 120 feet across entered the atmosphere above the Siberian forest and exploded at an altitude of 6-10 km above the ground. It released about 185 times the energy released by the detonation of the bomb over Hiroshima. The resulting shock wave stripped the branches and bark off the trees immediately below the air burst, felled the trees for tens of kilometers around and blasted a large amount of debris into the atmosphere.
There wasn’t a scientific expedition to the site of the explosion until 19 years after it happened.
More Info
See the Introductory Post
See other Daily Curiosities Posts
POSTED by: Scott McKittrick on 10/06/2009
In late 1977, two small spacecraft launched from earth and began a mission to visit Jupiter and Saturn and learn more about them. 32 years later, these two spacecraft, called Voyager 1 and Voyager 2 are flying at incredible speeds out of the solar system and into the vast regions of interstellar space; all the while, sending back new data about what they find so far away from our planet. Both spacecraft have now crossed the termination shock and are flying traveling through the Heliosheath, the final layer of the solar system before leaving the Heliosphere and reaching interstellar space.
The spacecraft are powered by radioisotope generators that are expected to provide power until about 2025. However, as the generators lose capacity, various experiments will need to be shutdown in order to conserve power.
It is unknown when the Voyager spacecraft will reach the Heliopause.
Both Voyager 1 and Voyager 2 also carry a small gold plated copper phonographic record (The Voyager Golden Record), containing greetings in various languages, music and pictures. These records are there in case one of the spacecraft is found by extraterrestrial beings, though the chance of this happening is next to nothing.
More Info
See the Introductory Post
See other Daily Curiosities Posts
POSTED by: Scott McKittrick on 09/30/2009
Microgravity (aka weightlessness), it is a condition that causes all sorts of interesting phenomena…like bubbles that sit in water without floating.
The reason that bubbles float on earth has to do with the relative density of water compared to air. At sea level, water is 784 times denser than air and so gravity pulls it down towards the earth more than it does air, thus the air rises out of the water. Perhaps a more accurate way to see it would be to say that the water sinks. In microgravity, such as being on the space shuttle in orbit, there is no gravity to pull harder on the water than on the air, so the air has no reason to rise and ends up staying in the middle of the water. NASA has put together some very interesting videos on the behavior of water and bubbles in space. See them here.
Difference in density also explains why steel sinks but wood floats. For information on why steel boats float instead of sink, see Bouyancy.
More Information
POSTED by: Scott McKittrick on 07/21/2009
Yesterday (today still for me, since its 1am and I haven’t gone to bed), was the 40th anniversary of the Apollo Moon Landing. 40 years ago, Neil Armstrong, Edwin “Buzz” Aldrin, and Mike Collins left the Earth atop the massive Saturn V rocket and hurtled more than 200,00 Kilometers into the pages of history. After achieving lunar orbit, Armstrong and Aldrin flew the LEM Eagle to the surface of the Moon and became the first men to set foot on another world, marking the success of a decade of hard work.
Nothing compares to the scope of the achievement of all the men and women who labored for almost a decade to make this moment and the subsequent moon landings possible.
It was very fun to follow the mission on WeChooseTheMoon.org.
