many people remember exactly where they were when humans first set foot on the
moon but for those of us born after 1969 we've got to hang on to other epic
moments in spaceflight history I vividly remember watching the first launch of
the space shuttle when I was nine years old and I remember when NASA's Voyager
spacecraft swept past each of the outer giant planets in the solar system
Jupiter Saturn Uranus and Neptune it's been nearly 40 years since the voyagers
blasted away from Earth on their voyage into interstellar space and here's the
most amazing part they're still operational
still working hard to deliver us science from the outer solar system as I record
this video Voyager 1 is the most distant object ever created by human beings more
than 20 billion kilometres away from Earth more than four times the distance
to Pluto and here's a really mind-bending part Voyager 1 is the
farthest object we know of in the entire solar system but I'm getting hand myself
it's time to look back nearly 40 years and remember the Voyager missions and
their amazing accomplishments over the decades the Voyager missions were
developed in the early 1970s to take advantage of a rare alignment of the
giant planets in the solar system with the right launch speed trajectories and
planetary slingshots it could be possible to send a spacecraft past each
of the large planets in the solar system Jupiter Saturn Uranus and Neptune over
the course of their primary mission the spacecraft were to visit Jupiter and
Saturn but the mission controllers couldn't help but add Uranus and Neptune
to the list reprogramming the spacecraft as they explored the solar system to
continue onward between them the twin spacecraft observed four planets
48 moons as well as the Rings and magneto spheres their original mission
should have only been five years but they were extended to 12 and now almost
40 years later they're still going and going
Voyager 2 lifted off first on August 20th 1977 with the trajectory that gave
it the option to Uranus and Neptune later on its trip
Voyager one went 2nd on September 5th 1977 but followed a faster shorter
trajectory their first destination was Jupiter the largest planet in the Solar
System forger one arrived at the giant planet on March 5th 1979 passing within
a few hundred thousand kilometers of Jupiter's cloud tops it observed the
incredible storm systems in Jupiter's upper atmosphere and helped to discover
that Jupiter like Saturn's has a ring system because the biggest discovery of
Jupiter was with its moons the voyagers discovered that Jupiter's innermost
large moon Io has active volcanoes spewing lava high into space
the percent volcanism had been seen anywhere else in the solar system they
observed cracks on the surface of Europa and Ganymede indicating that both worlds
have some kind of subsurface ocean beneath an icy crust between them the
two spacecraft took more than 33,000 pictures of Jupiter and its moons next
up with Saturn and in my opinion the highlight of the whole Voyager program
although the ringed planet had already been visited by pioneer 11 in 1979 the
voyagers took things to the next level Voyager 1 arrived in November 1980 and
sent back high-resolution images of Saturn as well as its moons and rings
where Jerome was selected to make a closer flyby of Titan Saturn's largest
moon and the second largest moon in the solar system it discovered that Titan's
atmosphere is mostly made of nitrogen like Earth unfortunately it's too dense
to see down to the surface we need to wait for Cassini to show us what's down
there Voyager 1 discovered that Saturn's upper
atmosphere seems to contain like helium then scientists we're expecting which
indicates that the helium is slowly sinking down into the center of the
planet Voyager 2 arrived nine months later in August 1981 passed within 40
1,000 kilometers of Saturn and made even more observations of the planet and its
environment together the voyagers provided the first
analyzing hint of geysers emanating from Enceladus which Cassini confirmed
decades later and together they discovered the huge hexagonal vortex the
planets North Pole at this point the voyagers parted company
Voyager 1 continued on from Saturn with no more destinations while Voyager 2
performed a slingshot maneuver that put it on course to visit the outer ice
giants would you - still had two more destinations to go its next destination
was Uranus in January 1986 when it passed within 80 1,500 kilometers of the
planet this was the first and so far last time that any spacecraft has ever
reached Uranus these are the only close up pictures that we have of Uranus and
its moons thanks to Voyager 2 the spacecraft made
several new discoveries about Uranus the planet was flipped over onto its side by
some collision in the ancient path and Voyager discovered that not only does
Uranus have a magnetosphere but it's twisted into a corkscrew shape
that trails behind the planet as it orbits the Sun would you observe the
planet swings and collection of moons but perhaps the strangest discovery was
its moon Miranda would you two observed huge cracks and canyons on the surface
of Miranda as deep as 20 kilometers is it possible that the moon was smashed up
in the ancient past and then reformed from the shattered pieces the final stop
on the Grand Tour was Neptune visited by Voyager 2 in summer of 1989 I remember
this image vividly on television and in the newspapers it was the summer I
graduated from high school Voyager 2 passed just four thousand nine hundred
and fifty kilometers above Neptune's North Pole closer than any other object
during its voyage since this was Voyager 2 the last stop NASA was willing to
throw caution to the wind the spacecraft discovered that the winds on Neptune
blow faster than anywhere else in the solar system triple the speed of Jupiter
discovers that the planet has storms swirling across its surface like the
other giant planets it fine-tuned estimates of Neptune's mass discovered
six new moons and observed its ring system up
close for the first time and perhaps the most tantalizing was the close-up images
of Neptune's moon Triton a bizarre moon that dominates the Neptunian system and
orbits backwards from all the other large moons in the solar system
scientists think it was a captured Kuiper belt object stolen in the ancient
past with Triton in its rear view mirror Voyager 2 carried on out in a deep space
the Grand Tour was over but the voyagers still had more science to do and we'll
talk about that in a moment but first I'd like to thank Anton velocity John
Clarke Alex Pucelle and the rest of our 765 patrons for their generous support
if you love what we're doing and you want to get in on the action
head over to patreon.com/scishow verse today in august 2012 the spacecraft
officially made the leap to interstellar space escaping the sun's heliosphere now
in case you're not familiar the heliosphere is a region of ionized
plasma that surrounds the Sun blown out into space by the solar wind like an
inflated balloon this bubble is what separates the Sun solar wind from the
collective solar winds of all the other stars in the Milky Way and the voyagers
cross the region dominated by the Sun into interstellar space even though
Voyager 1 is now more than 20 billion kilometres away still emit signals of
about 23 watts but as much power as a refrigerator light bulb although by the
time you reach Earth they're a billion billionth of a watt and yet they
continue onwards now let's look into the future what happens next should be
spacecraft at the current pace they'll reach the Oort cloud in about 300 years
that's a huge cloud of icy objects thought to surround the solar system and
be the source of the long period comets that we see from time to time
unfortunately they'll be dead much sooner than that sometime in the next
couple of years as the radioisotope thermoelectric generator that powers the
spacecraft isn't going to be able to give it enough electricity to keep
equipment going the gyroscopes that allow NASA to reorient the spacecraft
will cease operations the data recorders will shut down and in 2020 or so NASA
will start to shut down their scientific instruments one by one as the power
levels continue to decline finally by 2025 to 2030
the voyagers won't have enough electricity to do anything else
we got 40 years from them but we'll be lucky to get 50 and then they'll
continue to drift off into the darkness their journeys of your cloud will last
30,000 years and in 40,000 years or so they'll get within a couple of
light-years of the star Goliath four four five but the voyagers were built to
last each was equipped with a golden record
containing sounds and images selected by Carl Sagan and others aliens who
encounter the voyagers will enjoy the sounds of Earth like whale surf and the
wind as well as musical selections oh and a handy map to earth using pulsars
the records were made of gold and etched for the sample of uranium 238 which has
a half-life in the billions of years future alien civilizations could use
this to determine when the voyagers were constructed and ruin the co-creative
cosmos says that the records themselves replayable for a billion years the
Voyager spacecraft were some of the most ambitious robotic spacecraft humans ever
built they carried our senses out to Jupiter and Saturn and then Voyager 2
helped us see Uranus and Neptune for the first time ever we still depend on and
reference the images and observations from these hard-working spacecraft for
so much of our understanding of the outer solar system almost when they're
gone what about you do you have any nostalgic memories about the Voyager
spacecraft eliminating thoughts in the comments inter next episode we look at
the Van Allen belts the radiation that surrounds the earth another dangerous
hazard that astronauts face is if they need anymore ways that the universe is
trying to kill them that's next time of course I got a playlist of videos about
the Voyager missions first up a video from NASA a few years ago when Voyager 1
reached celer space Tom Scott visits the Voyager
control room at NASA Vsauce has a message for the future including
voyagers golden record and then a pair of longer lectures from NASA scientists
working with Voyager and that starts right now
next yet disagree
For more infomation >> After tragedy, how is Hamilton County Fair inspecting rides? - Duration: 1:37. 
For more infomation >> Video: Tom Messner is looking at more sun & a warm-up. 8.8.17 - Duration: 4:06. 
For more infomation >> Counterfeit watch sold to pawn shop - Duration: 1:32. 
For more infomation >> Riviera Beach Public Works building deemed unsafe - Duration: 1:05. 
For more infomation >> Charter school in Titusville to open after failed inspections - Duration: 1:14. 
For more infomation >> U.S. Intel: North Korea Successfully Miniaturized Nuclear Warhead | MSNBC - Duration: 3:09. 
For more infomation >> North Korea Can Push 'Hard Without Much Consequence' | MTP Daily | MSNBC - Duration: 7:38. 
For more infomation >> MSA Sports Network turns to crowdfunding - Duration: 1:57. 
For more infomation >> Video: Hogan calls for dredging at Conowingo Dam - Duration: 2:00. 
For more infomation >> Police interviews offer differ accounts in teen's slaying - Duration: 1:33. 
For more infomation >> Gas leak capped in Wellington - Duration: 1:06. 
For more infomation >> Harmony Mendoza's Tuesday afternoon forecast - Duration: 1:31. 
For more infomation >> Car plunges 150 feet in Vandergrift - Duration: 0:31. 
For more infomation >> CABO de TERRA: Qual COR usar? 🔌 - Duration: 4:16. 
Không có nhận xét nào:
Đăng nhận xét