00:00This planet, yeah, the one right here, shouldn't exist, but it does.
00:05A newly discovered planet rotates around a star that's much smaller and dimmer than our Sun.
00:10The planet, however, is enormous.
00:13Such a tiny star couldn't create it, so it's like finding an ostrich egg in a chicken coop.
00:20A team at Penn State built a special tool called the Habitable Zone Planet Finder.
00:25It's an instrument that's supposed to find planets around dim, cool stars.
00:30It's connected to a big telescope in Texas.
00:32The tool looks at the light from these stars, which is mostly in the near-infrared, beyond what our eyes can see.
00:38This gadget can spot changes in a star's speed caused by a planet.
00:43If the star movement slightly changes, that means there must be a gravitational pull nearby.
00:48Years ago, this technique helped find the first known exoplanet around a star like our Sun.
00:53Today, we've improved this method to make more precise measurements.
00:57Our main goal is to find Earth-like planets.
01:00They should be rocky and located in habitable zones, areas around stars where liquid water could exist.
01:07The Doppler technique isn't that great at finding Earth-like worlds yet, but works well for cool, dim stars.
01:13And that's how we discovered the impossible LHS 3154b.
01:18Planets usually form in disks made of gas and dust in space.
01:25Picture a flat, spinning cloud of tiny particles.
01:28These particles come together and stick to each other, creating a flat, rotating disk.
01:34Over time, these tiny bits combine to form a solid core.
01:37This is the starting point for a planet.
01:40Once the core is there, it attracts more dust and even gas like hydrogen and helium.
01:45But making a planet this way isn't easy.
01:48They need a lot of stuff, mass, and materials.
01:52This process is called core accretion.
01:55Stars are a huge help in that process.
01:57Usually, big stars have more gravity, so they can gather more stuff to form planets.
02:02But the star we discovered recently isn't very big.
02:06It's nine times smaller than our Sun.
02:08A star this small shouldn't have a big enough disk to make a heavy planet.
02:12To do that, its disk should have been at least 10 times bigger.
02:17But this heavy planet, LHS 3154b, exists.
02:23Now, this mysterious planet is 13 times heavier than our Earth.
02:28It's similar in size to Neptune.
02:30It's about 50 light-years away from us in the Hercules constellation,
02:33which, in space terms, is very close.
02:36The planet is also super close to its star,
02:39completing one year in almost four days.
02:42This discovery is making scientists rethink their ideas
02:45about how planets and stars come into existence.
02:49There are new theories coming around.
02:51For example, a theory called gravitational instability.
02:55It says that, instead of the pieces coming together bit by bit,
02:59the material in the disk collapses all at once,
03:02directly creating a planet.
03:04But even with this theory,
03:06it's hard to explain how such a heavy planet could form
03:09without a really massive disk.
03:11It'll take us some time to figure out the truth.
03:15This isn't the first planet that makes us doubt our theories.
03:19Recently, scientists found another planet called Hala.
03:22This planet is orbiting a star called Bektu.
03:25And just like the previous one,
03:26it shouldn't really exist.
03:28It's way too close to its star.
03:30Stars change a lot during their lives.
03:32Normally, when a star becomes big
03:34and prepares to leave this world,
03:36it's called the red giant stage.
03:39A star like that tends to destroy
03:41or push away any nearby planets,
03:43creating a huge mess.
03:45Hala rotates around a red giant,
03:47and it should have been swallowed or destroyed
03:49by the expanding star a long time ago.
03:52But it's still hanging there.
03:54Even though Bektu has already started burning helium
03:57and shrunk to a smaller size than expected,
04:00Hala isn't bothered in the slightest.
04:02Scientists called Hala a forbidden planet.
04:06This discovery challenges what we thought
04:08about how planets survive near aging stars.
04:11It raises two theories.
04:13One suggests that Bektu was once two stars,
04:16a white dwarf and a red giant.
04:19Hala orbited them both,
04:20and they merged before the red giant fully expanded.
04:23This allowed Hala to survive,
04:25because the extra helium from the white dwarf
04:28prevented the red giant from growing too much.
04:30The second theory says that Hala formed from the debris
04:33created when the two stars merged.
04:36In this scenario,
04:37Hala would be a very young planet
04:39orbiting an elderly star.
04:41Astronomers plan to continue studying Hala
04:44and look for more planets like that.
04:48Another oddball, besides me,
04:50is called LTT 9779b.
04:54This one scares us too,
04:55because it's too shiny.
04:58The planet reflects 80% of the light from its star.
05:01Regular mirrors reflect from 85% to almost 100% of light,
05:05which means that this mysterious planet
05:07should look like a rough mirror
05:09with aluminum or silver-like reflections.
05:11This is another Neptune-sized planet.
05:15It's located 268 light-years from us
05:17and was discovered by NASA's TESS spacecraft.
05:21It completes a full rotation around its star
05:23in just 19 hours.
05:25It's so close to its star
05:27that it's scorching high,
05:28reaching temperatures over 3,600 degrees Fahrenheit.
05:32Normally, planets this close lose their atmosphere
05:35and turn into bare rocks.
05:37But this one breaks the rules again.
05:39Now, this time,
05:43we know the secret of its survival.
05:45It's because of the planet's shiny metallic clouds,
05:48which are made of glass and titanium salt.
05:51These clouds rain titanium onto its hot surface.
05:54They also reflect a lot of the light,
05:56preventing the planet from getting too hot
05:58and losing its atmosphere.
06:00It's like having a mirror shield.
06:02This planet's size also surprised scientists.
06:05It's way bigger than Earth.
06:07Other planets this close to their stars
06:09are either much bigger gas giants
06:11or small, rocky planets.
06:13This planet is a smaller gas giant,
06:16and scientists didn't expect it to exist
06:18so close to its star.
06:20This is the shiniest planet ever found,
06:22even shinier than Venus.
06:24But despite its cool appearance,
06:26it's probably not a friendly place for life
06:28because of its extreme temperatures
06:30and strange metallic rain.
06:32And our final rule-breaker
06:37is a planet called WASP-107b.
06:41Scientists discovered it
06:42using the James Webb Space Telescope.
06:44It's located around 208 light-years from us
06:47in the Virgo constellation.
06:49It's also fast
06:50and completes an orbit around its star
06:52in just six days.
06:54This is a super-Neptune exoplanet.
06:57It's similar to Jupiter in some ways,
06:59including the same size
07:01and scorching hot temperatures.
07:03But the main difference is that
07:04it's much lighter, weaker, and less dense.
07:07This is the least dense planet
07:08we've discovered so far.
07:10After researching some more,
07:12we also found that it has a tail.
07:15The helium on the planet
07:16extends beyond the transit egress.
07:18The planet is slowly losing its atmosphere
07:21due to extreme ultraviolet radiation
07:23from the star.
07:24This creates a comet-like tail.
07:27So it looks like a fluffy comet.
07:31But that was just the beginning.
07:34The planet's low density, or fluffiness,
07:36allowed astronomers to study
07:38its atmosphere in detail.
07:40They found some surprising things,
07:42like water vapor and clouds
07:44made of fine silicate particles,
07:46which are like really fine-grained sand.
07:49The planet's host star
07:50doesn't emit a lot of high-energy light.
07:52But since WASP-107b is so loose,
07:56the light can penetrate
07:57deep into its atmosphere.
07:59This creates sulfur dioxide,
08:01that smell when you light a match.
08:03In other words,
08:04it's a fluffy planet that rains sand
08:06and smells like matches.
08:08The researchers think
08:09the sand clouds in the atmosphere
08:10form in a similar way
08:12to clouds on Earth.
08:13They just have droplets of sand
08:15instead of water.
08:16These sand droplets condense,
08:18fall,
08:19turn into silicate vapor
08:20and hot layers within the planet,
08:22and then rise again
08:23to form clouds once more.
08:25And, once again,
08:27this planet couldn't have formed
08:28in its current spot.
08:30Astronomers say that it likely
08:31moved closer to its star
08:32from a birth orbit
08:34because it was attracted
08:35by some heavier neighbor.
08:37It also follows
08:38a retrograde orbit,
08:39meaning it orbits
08:40in the opposite direction
08:42to its star's rotation.
08:43All these discoveries
08:45are changing how we understand
08:46planets and their atmospheres,
08:48giving us new insights
08:49into the mysteries
08:50of our own solar system.
Comments