The Science of Interstellar - Black Hole [YouTube Video]
After spending a month attached to the ISS, the Dragon spacecraft succesfully lands in the pacific and is shipped back to land.
via reddit
A magnetar is a type of neutron star with an extremely powerful magnetic field, the decay of which powers the emission of high-energy electromagnetic radiation, particularly X-rays and gamma rays.1
History
On March 5, 1979, several months after dropping probes into the toxic atmosphere of Venus, two Soviet spacecraft, Venera 11 and 12, were drifting through the inner solar system on an elliptical orbit. It had been an uneventful cruise. The radiation readings on board both probes hovered around a nominal 100 counts per second. But at 10:51AM EST, a pulse of gamma radiation hit them. Within a fraction of a millisecond, the radiation level shot above 200,000 counts per second and quickly went off scale.
Eleven seconds later gamma rays swamped the NASA space probe Helios 2, also orbiting the sun. A plane wave front of high-energy radiation was evidently sweeping through the solar system. It soon reached Venus and saturated the Pioneer Venus Orbiter’s detector. Within seconds the gamma rays reached Earth. They flooded detectors on three U.S. Department of Defense Vela satellites, the Soviet Prognoz 7 satellite, and the Einstein Observatory. Finally, on its way out of the solar system, the wave also blitzed the International Sun-Earth Explorer.
The pulse of highly energetic, or “hard,” gamma rays was 100 times as intense as any previous burst of gamma rays detected from beyond the solar system, and it lasted just two tenths of a second. At the time, nobody noticed; life continued calmly beneath our planet’s protective atmosphere. Fortunately, all 10 spacecraft survived the trauma without permanent damage. The hard pulse was followed by a fainter glow of lower-energy, or “soft,” gamma rays, as well as x-rays, which steadily faded over the subsequent three minutes. As it faded away, the signal oscillated gently, with a period of eight seconds. Fourteen and a half hours later, at 1:17AM on March 6, another, fainter burst of x-rays came from the same spot on the sky. Over the ensuing four years, Evgeny P. Mazets of the Ioffe Institute in St. Petersburg, Russia, and his collaborators detected 16 bursts coming from the same direction. They varied in intensity, but all were fainter and shorter than the March 5 burst.
Astronomers had never seen anything like this. For want of a better idea, they initially listed these bursts in catalogues alongside the better-known gamma-ray bursts (GRBs), even though they clearly differed in several ways. In the mid-1980s Kevin C. Hurley of the University of California at Berkeley realized that similar outbursts were coming from two other areas of the sky. Evidently these sources were all repeating unlike GRBs, which are one-shot events [see “The Brightest Explosions in the Universe,” by Neil Gehrels, Luigi Piro and Peter J. T. Leonard; Scientific American, December 2002]. At a July 1986 meeting in Toulouse, France, astronomers agreed on the approximate locations of the three sources and dubbed them “soft gamma repeaters” (SGRs). The alphabet soup of astronomy had gained a new ingredient.
Another seven years passed before two of us (Duncan and Thompson) devised an explanation for these strange objects, and only in 1998 did one of us (Kouveliotou) and her team find remains of a star that exploded 5,000 years ago. Unless this overlap was pure coincidence, it put the source 1,000 times as far away as theorists had thought—and thus made it a million times brighter than the Eddington limit. In 0.2 second the March 1979 event released as much energy as the sun radiates in roughly 10,000 years, and it concentrated that energy in gamma rays rather than spreading it across the electromagnetic spectrum.2
About 26 magnetars are known (see here).
1 http://en.wikipedia.org/wiki/Magnetar
2 http://solomon.as.utexas.edu/~duncan/sciam.pdf
The Cassini probe took a picture of Saturn that includes Earth in it!
Cassini has actually taken a ton of cool photos of Saturn if you want to check those out in the wake of last week’s planets podcast.
Soviet Cosmonaut Sergei Krikalev stuck in space during the collapse of the Soviet Union in 1991
Unable to return home, he ended up having to stay in space until further notice.
The cosmonaut eventually returned back to earth on March 25, 1992, after 10 months in orbit - to a nation that was very different to what it was when he had left. The Soviet Union had fractured into 15 nations, presidents had changed, and even his hometown of Leningrad had become St. Petersburg.
Interestingly, at the time, Krikalev was supposed to serve in the military reserves, and was almost issued a warrant for desertion – before the army realised that their reserve soldier was not even on the planet.
This one is technically not yet history, because at the time of posting, the little craft has about half an hour left to go. That said, let’s proceed.
In 2017, NASA’s Cassini space probe ended its twenty-year mission at Saturn. After a nearly-seven-year-long journey there, it orbited the ringed planet for 13 years and just over two months, gathering copious amounts of information about the planet, said rings, and many of its moons. It landed an ESA probe called Huygens on Titan, the first-ever soft landing in the outer Solar System. It discovered lakes, seas, and rivers of methane on Titan, geysers of water erupting from Enceladus (and passed within 50 miles of that moon’s surface), and found gigantic, raging hurricanes at both of Saturn’s poles.
And the images it returned are beautiful enough to make you weep.
On this day in 2017, with the fuel for Cassini’s directional thrusters running low, the probe was de-orbited into the Saturnian atmosphere to prevent any possibility of any contamination of possible biotic environments on Titan or Enceladus. The remaining thruster fuel was used to keep the radio dish pointed towards Earth so the probe could transmit information about the upper atmosphere of Saturn while it was burning up due to atmospheric friction.
This is us at our best. We spent no small amount of money on a nuclear-powered robot, launched it into space, sent it a billion miles away, and worked with it for two decades just to learn about another planet. And when the repeatedly-extended missions were through, we made the little craft sacrifice itself like a samurai, performing its duty as long as it could while it became a shooting star in the Saturnian sky.
Rhea occulting Saturn
Water geysers on Enceladus
Strange Iapetus
Look at this gorgeousness
A gigantic motherfucking storm in Saturn’s northern hemisphere
Tethys
This image is from the surface of a moon of a planet at least 746 million miles away. Sweet lord
Mimas
Vertical structures in the rings. Holy shit
Titan and Dione occulting Saturn, rings visible
Little Daphnis making gravitational ripples in the rings
That’s here. That’s home. That’s all of us that ever lived.
Saturn, backlit
A polar vortex on the gas giant
Icy Enceladus
(All images from NASA/JPL)
Heya, if you like space maybe you’ll like this comic? It’s one of my favorites and it’s ending soon and it’s all online for freebies! The spaceships are fish and folks get to go around fixing up abandoned ruins in space. It’s utterly beautiful. It’s also ending this month!
We’ll make it out eventually.
http://www.onasunbeam.com/
(New chapters coming soon)
On Tuesday, April 4 at 3 p.m. EDT (noon PDT), At Jet Propulsion Laboratory, the Cassini team host a news briefing to discuss the mission’s Grand Finale.
Tune in Tuesday: youtube.com/nasajpl/live
Cassini left Earth with less than 1/30th of the propellant needed to power all her adventures at Saturn. The navigation team used the gravity of Saturn’s giant moon Titan to change course and extend the spacecraft’s exploration of Saturn. Titan also provides the gravity assist to push Cassini into its final orbits.
More on Cassini’s navigation: saturn.jpl.nasa.gov/mission/spacecraft/navigation/
Cassini is an orbiter that was named for 18th century astronomer Giovanni Domenico Cassini. She was designed to be captured by Saturn’s gravity and then explore it in detail with a suite of 12 powerful science instruments.
More on the Spacecraft: saturn.jpl.nasa.gov/mission/spacecraft/cassini-orbiter/
Cassini carried the European Space Agency’s Huygens Probe, which in 2005 descended through Titan’s thick, perpetual clouds and made the most distant landing to date in our solar system.
More on Huygens: saturn.jpl.nasa.gov/mission/spacecraft/huygens-probe/
Your mobile phone likely captures dozens of megapixels in images. Cassini, using 1990s technology closer to one megapixel cameras, has returned some of the most stunning images in the history of solar system exploration.
Cassini Hall of Fame Images: go.nasa.gov/2oec6H2 More on Cassini’s Cameras: saturn.jpl.nasa.gov/imaging-science-subsystem/
Those great images have inspired artist’s and amateur image processors to create truly fantastic imagery inspired by the beauty of Saturn. Feeling inspired? There’s still time to share your Cassini-inspired art with us.
Cassini Inspires Campaign: saturn.jpl.nasa.gov/mission/cassiniinspires/
Two decades is a long time to live in the harsh environment of outer space (respect to the fast-approaching 40-year-old twin Voyager spacecraft). Launched in 1997, Cassini logged a lot of milestones over the years.
Explore the Cassini Timeline: saturn.jpl.nasa.gov/the-journey/timeline/
And, you can read it. Week after week going back to 1997, Cassini’s adventures, discoveries and status have been chronicled in the mission’s weekly significant events report.
Read It: https://saturn.jpl.nasa.gov/news/?topic=121
Cassini was the prototype for NASA’s Eyes on the Solar System 3-D visualization software, so it’s fitting the latest Cassini module in the free, downloadable software is the most detailed, elaborate visualization of any mission to date.
Fly the Mission - Start to Finish: http://eyes.nasa.gov/cassini
In addition to all the new information from 22 orbits in unexplored space, Cassini’s engineers reprogrammed the spacecraft to send back details about Saturn’s atmosphere to the very last second before the giant planet swallows her up on Sept. 15, 2017.
More on the Grand Finale: saturn.jpl.nasa.gov/grandfinale
Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com
A podcast project to fill the space in my heart and my time that used to be filled with academic research. In 2018, that space gets filled with... MORE SPACE! Cheerfully researched, painstakingly edited, informal as hell, definitely worth everyone's time.
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