Scientific Illustration

sciencecenter:

35 years later, Voyager spacecraft nearing the edge of the solar system

In the fall of 1977, NASA launched the two Voyager spacecraft, which were designed to study Jupiter and Saturn and then continue on to the limits of the solar system. Today, they are each more than 14 trillion kilometers from the sun and nearing the “bowshock,” the transitional region where the solar wind collides with gas from interstellar space. Within five years, the Voyager crafts should be completely clear of our solar system’s influence. That far, light must travel more than 30 hours from the sun before it reaches the spacecraft.

What’s especially interesting about the Voyager expedition is the backstory behind the mission. Rocket scientists around the time of Sputnik were trying to design a rocket that could overpower the sun’s gravitational pull, a very tough task. A trip of more than a few months using this brute force method was out of the question. Cue Michael Minovitch, who in 1961 set out to solve the three-body problem, the question of how gravity from both the sun and the Earth would impact a third body, in this case the spacecraft. Some of science’s greatest minds, including Newton, were stumped by the task. However, with the use of one of the first computers, Minovitch was able to demonstrate how exploiting the sun’s gravitational field to slingshot a spacecraft deep into space. One of Minovitch’s simulations used this slingshot approach to accelerate using the gravitational fields of the sun as well as Saturn, Jupiter, Uranus and Neptune. The planets were only on the same side of the solar system in 1977, and the same opportunity wouldn’t present itself again for 176 years. Scientists luckily realized the potential in Minovitch’s idea, and launched the Voyager crafts with enough power to last for decades in space and with instruments to study the solar system’s furthest reaches. Today, although the signal from the spacecraft represents only a billionth of a billionth of a billionth of a watt once it reaches Earth, the ships keep sending back data and contribute to new discoveries.

Quick Links

• Voyager Mission - NASA
• The Math That Made Voyager Possible - BBC

(via geologise)

rhea137:

Popular Science - Google Books

Biggest artificial meteor
An Apollo 13 “spectacular” will be the meteor-like crash on the moon of the great Saturn V rocket’s whole top stage and instrument unit, totaling more than 15 tons’ weight. Instead of being aimed past the moon as before, the rocket stage will be targeted at a point on the surface about 125 miles from Apollo 12’s Ocean of Storms seismometer, which will register vibrations from the impact.
This will be a dramatic scale-up of the Apollo 12 experiment of crashing the empty 2 1/2-ton ascent stage of its Lunar Module on the lunar surface. The astounding result of that crash: The moon rang like a bell for nearly an hour, indicating some strange and unearthly underground structure. Intended to probe this subsurface formation with stronger and longer-range seismic waves, the impact of the heavier and faster-speeding Saturn stage should really make the moon clang! For good measure, Apollo 13 will also crash its own Lunar Module ascent stage, some 42 miles from a new seismometer that it will have emplaced on the moon’s surface.

PS
He began playing his shining trumpet with such power that the whole mountain rang.
— Johann Valentin Andreae, Die Chymische Hochzeit des Christian Rosencreutz, Strassburg, Zetzner, 1616, I, p. 4

(via mudwerks)

rhamphotheca:

The Hertzsprung–Russell diagram is a scatter graph of stars showing the relationship between the stars’ absolute magnitudes or luminosities versus their spectral types or classifications and effective temperatures. Hertzsprung–Russell diagrams are not pictures or maps of the locations of the stars. Rather, they plot each star on a graph measuring the star’s absolute magnitude or brightness against its temperature and color… (read more: Wikipedia)

rhamphotheca:

Diffuse gas—called plasma—flows outward from the sun as the “solar wind” and carries with it solar magnetic field lines that become entangled with the Earth’s own magnetic field lines. Location of “holes” were detected in indicated pink layers, near Earth… (read more: PhysOrg)

(Image: NASA)

itsfullofstars:

Lunar orbit rendezvous

discoverynews:

Dinosaur Freeway Found in Colorado

A bustling thoroughfare 98 million years ago was a coastal plain full of waterways.

(via onedimensional)

branchandblaze:

Trouvelot, The Planet Mars, 1877

mythologyofblue:

W.G. Evans, Chart of comets, star clusters and nebula, 1856

(the-rx)

(via keepyourpebbles)