00:00By now, I bet everyone knows this guy.
00:02Yes, it's Jupiter.
00:04In our solar system, the Sun's the boss and Jupiter's second in command.
00:09We all know Jupiter is huge, but just how huge?
00:12Put it this way.
00:14If Earth was an 8mm peanut, Jupiter would be a football or basketball,
00:18and the Sun would be a balloon about 1.2 metres across.
00:22Mass-wise?
00:23Apart from the Sun, take all seven other planets,
00:26multiply by 2.5, and you're close to Jupiter's mass.
00:30Despite its massive size, Jupiter is basically a giant gas ball.
00:3590% hydrogen, 10% helium, pretty much the same recipe as the Sun.
00:40But here's the crazy part.
00:42Calculations show that if Jupiter had absorbed just 80 times more mass during formation,
00:47its metallic core could have triggered nuclear fusion.
00:51Jupiter would have ignited, turning our solar system into a binary star system.
00:55But it missed by just that much, leaving Jupiter as a gas giant.
00:59It's like Jupiter was perfectly designed to protect Earth.
01:03Can't become a star, but has this massive body and magnetic field,
01:07sitting right at this crucial sweet spot.
01:10Many of you have heard Jupiter called Earth's guardian.
01:13Why?
01:14How intense is the pressure inside Jupiter?
01:16It's so crazy that hydrogen gets squeezed into liquid metal.
01:19Add Jupiter's insane spinning speed and you've got yourself a giant power generator
01:25with a magnetic field 20,000 times stronger than Earth's.
01:29As carbon-based lifeforms, we can't really sense this powerful field.
01:34But Jupiter's real protection comes from its massive gravitational pull.
01:38Small comets trying to reach Earth through Jupiter's orbit?
01:41Most get caught by Jupiter.
01:44Take the 1994 example.
01:46Comet Shoemaker-Levy 9.
01:48This comet was half the size of the Chicxulub asteroid that wiped out dinosaurs 65 million years ago,
01:54about 5 kilometers in diameter.
01:56As it headed toward Earth, Jupiter's gravity captured and ripped it apart.
02:01Earth's observatories watched it tear into 21 massive chunks that slammed into Jupiter.
02:06The biggest piece was 4 kilometers across, with impact energy equal to 60 trillion tons of TNT.
02:13All 21 pieces combined.
02:15That's a mind-boggling 400 trillion tons of TNT equivalent.
02:20About the same as detonating 50 Hiroshima bombs every second for a year.
02:25Compared to the dinosaur-killing Chicxulub impact, this was 40% of that energy.
02:30Models show if Shoemaker-Levy 9 had hit Earth,
02:3375% of all species would have gone extinct.
02:36Some humans far from impact might survive,
02:39but they'd face long-term famine and societal collapse.
02:43Impact dust would block sunlight for months to years,
02:45dropping global temperatures 10 to 20 degrees.
02:48If extreme weather lasted decades,
02:50humanity would likely regress to small tribal communities.
02:54Actually, Shoemaker-Levy 9's chance of hitting Earth was basically zero.
02:59Starweaver is just using it as an example here.
03:01I hope you guys understand this correctly.
03:04Over billions of years, Jupiter and our moon have indeed blocked countless impacts from reaching Earth.
03:10Jupiter's powerful gravity doesn't just give it 95 moons.
03:14It also shapes Jupiter's faint ring system.
03:17These dusty rings aren't as spectacular as Saturn's,
03:20but they quietly tell the story of our solar system's gravitational ballet.
03:25Jupiter's moons are fascinating.
03:27Io is the most volcanically active body in the solar system,
03:31with over 400 active volcanoes shooting sulfur plumes,
03:35500 kilometers high, basically a giant fireball.
03:39Europa is wrapped in thick ice,
03:41hiding more liquid water beneath than all Earth's oceans combined.
03:45Essentially a water world.
03:47It's also the only place besides Earth that might harbor life.
03:50Ganymede is our solar system's largest moon at 5,262 kilometers diameter.
03:57Bigger than Mercury and the only moon with its own magnetic field.
04:01Callisto.
04:02Created diary of 4 billion years.
04:05Virtually no geological activity.
04:07It's like the solar system's notebook,
04:09silently recording billions of years of history.
04:12Once Starweaver finishes covering all eight planets,
04:15we'll circle back to explore these amazing moons in detail.
04:18Earlier I mentioned Jupiter's 10-hour rotation.
04:22Actually 9 hours, 50 minutes.
04:24While Earth completes one rotation, Jupiter does 2.5.
04:27This incredible spin creates super hurricanes
04:30over 600 kilometers per hour on Jupiter's surface.
04:34Various chemicals mix and swirl in these storms,
04:37creating those red, yellow and white stripes we see.
04:40Why different colors?
04:41Still no definitive answer.
04:43One theory.
04:44Light-colored zones form from rising clouds of ammonia ice crystals.
04:48While dark belts form from sinking clouds.
04:51Jupiter's ultra-high rotation makes these cloud bands
04:54race parallel to its equator at hundreds of kilometers per hour.
04:58This relative motion creates cyclones and storms of various sizes.
05:02The biggest is the Great Red Spot.
05:04Big enough to fit three Earths side by side.
05:07This storm has raged for at least 350 years,
05:10sustained by Jupiter's internal heat convection.
05:12But why is it red?
05:14How long will it last?
05:16We simply don't know.
05:17As of May 2025, humans have sent eight probes to Jupiter since 1973,
05:23with Juno and Europa Clipper rewriting textbooks.
05:26Only Galileo, Juno and Europa Clipper are dedicated Jupiter missions.
05:30The others just flew by.
05:32Europa Clipper is worth a special mention.
05:35Launched October 14th, 2024.
05:37Expected to reach Jupiter's orbit in 2030.
05:41Its main goal?
05:41Detecting whether life exists beneath Europa's ice.
05:45It'll also study Jupiter itself.
05:47As mentioned, Europa is an ice-covered water world.
05:50Based on Galileo and Hubble observations,
05:52the subsurface ocean is 50 to 150 kilometers deep
05:56with twice Earth's water volume and Earth-like salinity.
06:00The seafloor has active volcanoes providing energy and minerals.
06:03The ice shell and atmosphere effectively shield
06:05against Jupiter's intense radiation.
06:08These conditions create a long-term stable environment for ocean life.
06:12Most exciting of all?
06:13Probes detected sulfur compounds, organic molecules
06:16and possible biological metabolites in Europa's ice geysers.
06:20If Europa Clipper actually finds life on Europa,
06:23human space exploration will take a giant leap forward.
06:26So far, Starweaver has covered Mercury, Venus, Mars and Jupiter.
06:31Most probes exploring these planets came from ESA,
06:34the United States, the Soviet Union and other countries.
06:38Speaking of Jupiter exploration,
06:40we Aussies haven't been sitting around doing nothing either.
06:43The Parkes radio telescope didn't just help Apollo 11.
06:47It's still tracking Jupiter probe signals right now.
06:50Sure, Australia might not have a huge population,
06:53but when it comes to space exploration,
06:55we never mess around.
06:57From pioneering radio astronomy to today's excellence
07:00in space technology and satellite communications,
07:02Australia proves that small nations can make big noise in space exploration.
07:07If any young friends are watching my videos,
07:09Starweaver hopes you start nurturing great dreams right now.
07:12Every great dream starts with today's hard work.
07:15So keep running.
07:16Keep reaching for the skies, my friends.
07:18Your telescopes, experiment kits,
07:20plus Australia's exceptional stargazing conditions and deep scientific traditions,
07:25might just be the starting point for future breakthroughs in human understanding.
07:29Under these southern cross skies,
07:31let's look up at the stars while keeping our feet on the ground.
07:35The future truly belongs to you.
07:37This is Cosmic Canvas.
07:38I'm Starweaver.
07:40If you love space exploration and unsolved mysteries too,
07:43please like and subscribe.
07:45See you next time.
07:46Love you all.
07:46Bye-bye.
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