- **Boulders Escaping from Asteroid Dimorphos:** Astronomers have made fascinating discoveries about numerous boulders seen swarming around the asteroid moon Dimorphos. This intriguing phenomenon is believed to be a result of the Double Asteroid Redirection Test (DART) asteroid impact mission conducted last year.
- **New Discoveries in Black Holes:** Exciting news from the world of astronomy as scientists have identified a novel and captivating feature of black holes. This discovery, seemingly straight out of a science fiction movie, has sparked the imagination of researchers and the general public alike.
- **Communication Disruption between Houston and International Space Station:** A significant incident occurred when a power outage disrupted the communication between Mission Control in Houston and the crew aboard the International Space Station. This event underscores the challenges faced by space agencies in maintaining uninterrupted communication with astronauts in orbit.
- **August Skywatch:** In this episode, we delve into various celestial phenomena occurring in August. Our focus will be on Antares, a giant star, as well as Barnard's star, the second nearest star system to the Sun. Additionally, we will discuss the eagerly anticipated annual Perseids meteor shower.
Become a supporter of this podcast: https://www.spreaker.com/podcast/spacetime-with-stuart-gary--2458531/support.
00:00:00
STUART GARY: This is Spacetime series 26 episode 93 for
00:00:04
broadcast on the fourth of August 2023. Coming up on
00:00:08
Spacetime boulders discovered escaping from the asteroid
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dimorphic new features discovered in black holes and
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Houston. We have a problem all that and more coming up on space
00:00:21
time.
00:00:23
GENERIC: Welcome to space time with Stuart Garry.
00:00:43
STUART GARY: Astronomers have discovered several dozen large
00:00:46
boulders swarming around the asteroid moon dimorphic.
00:00:50
Their detection comes in the wake of last year's Double
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Asteroid Redirection Test or DART asteroid impact mission.
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The mission was designed to see if NASA could nudge a potential
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earth impacting asteroid off course so that it would miss our
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planet. See, why would asteroids present a real collision hazard
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to earth.
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Scientists estimate that an asteroid measuring about 10
00:01:11
kilometers across, smashed into the earth 66 million years ago,
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wiping out 75% of all life on the planet, including all the
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non avian dinosaurs. But unlike the dinosaurs, humanity can
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avoid such a fate if we begin practicing.
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Now on how to knock earths approaching asteroids off
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course, trouble is this is far trickier than what's been
00:01:33
depicted in Hollywood movies. See planetary scientists first
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need to know how the asteroid was assembled. Are we talking
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about flying piles of rubble?
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In other words, loosely agglomerated rocks or are we
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talking about something more substantial, a single solid
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boulder the size of a mountain? This information will help
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provide strategies on how to successfully deflect a menacing
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asteroid. As a first step NASA did an experiment last year
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smashing an impact of spacecraft called DART into an asteroid to
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see what would happen.
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The half ton impact of spacecraft smacked into the
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asteroid dimorphic on September 26th at approximately 23
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kilometers per hour, the impact was so severe. It altered
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dimorphic orbit around the larger asteroid Diddy Mos by
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around half an hour.
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Astronomers using the Hubble space telescope have been
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continuing to follow the evolving aftermath of the
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collision and they've now discovered several dozen
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boulders were lifted off the asteroid following the smash up
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a report in the Astrophysical Journal letters claims the
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Hubble images show boulders looking like a swarm of bees
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very slowly moving away from the asteroid.
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This might mean that smacking an earth approaching asteroid
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itself could result in a cluster of threatening boulders heading
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in our direction. In other words, instead of one single big
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asteroid, you could have a whole bunch of little ones.
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Now based on Hubble photo Mery, the 37 free flung boulders range
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in size from around one to something like 8 m across. And
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although they're traveling with the asteroid. They're also
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slowly drifting away from it a little more than one kilometer
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per hour.
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The total mass of these detected boulders is thought to be about
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one per cent of the mass of dimorphic itself. The study's
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lead author David Joette from the University Of California,
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Los Angeles says it's a spectacular observation showing
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a cloud of boulders carrying mass and energy away from the
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impact target.
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And the numbers sizes and shapes of the boulders are all
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consistent with them having been knocked off the surface of
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dimorphic by the impact. Now, this tells scientists for the
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first time what happens when you hit an asteroid and see material
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coming off. It.
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Duet says it opens up a new dimension for studying the
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aftermath of the DART experiment using the European Space
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Agency's upcoming Hera spacecraft which will arrive at
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the binary asteroid system in 2026. Hera will perform a
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detailed post impact survey of the target asteroid and the
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boulder cloud will still be in the process of dispersing when
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Hera arrives.
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Duet says it's like a very slowly expanding swarm of bees
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that eventually will spread along the binary pair's orbit
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around the Sun. He says the boulders are most likely not
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shattered pieces of the asteroid caused by the impact, but rather
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they were boulders already scattered on the asteroid
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surface.
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The type seen during the last close up images taken by the
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DART spacecraft just two seconds before the collision when it was
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about 10 kilometers above the surface. Joette estimates that
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the impact shook about two per cent of the boulders off the
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asteroid surface.
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He says the boulder observations by Hubble also give an estimate
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for the size of the DART impact crater. He says the boulders
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could have been excavated from a circle about 50 m across on the
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surface of dimorphic. Hero will eventually determine the actual
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size of the crater.
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Long ago, dimorphic may have been formed from material shed
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into space by the larger asteroid dimos.
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The parent body may have spun up too quickly or it could have
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lost material through a Glans in collision with another object.
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The ejected material then formed a ring that gravitationally
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coalesced over time to form dimorphic and this would make
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dimorphic a flying rubble pile of rocky debris loosely held
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together by the relatively weak pull of gravity.
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Therefore, Duet says the interior is probably not solid
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but is a structure more like a bunch of grapes. It's not clear
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how the bowlers were lifted off the asteroid surface.
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They could have been part of an ejector plume that was
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photographed by Hubble and other observatories during the DART
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impact or a seismic wave from the impact could have rattled
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through the asteroid sort of like hitting a bell with a
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hammer shaking loose the surface rubble.
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Duet says that monitoring the boulder's future movements may
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provide enough data to pin down their precise trajectories and
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that will allow scientists to determine in which directions
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they were launched from the surface. This is space time
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still to come.
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Astronomers have identified a new feature of black holes. It
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sounds like it may have come straight out of a science
00:06:12
fiction novel. And Houston, we have a problem, the blackout
00:06:16
that affected the Johnson Space Center, all that and more still
00:06:19
to come on space time.
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Astronomers have identified a new feature of black holes that
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sounds like it may have come straight out of a science
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fiction novel. They've detected a quasi periodic oscillation
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signal embedded deep in the micro quasar beaming out of a
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distant black hole, black holes are immense gravitational wells
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created by the death of massive stars in core collapsed
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supernova explosions.
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The gravitational force of these objects is so strong that the
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escape velocity from a black hole would exceed the speed of
00:07:08
light. And since nothing can travel faster than light,
00:07:12
nothing, not even light can escape a black hole. Hence the
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name, once beyond the black hole's event horizon, a sort of
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point of no return matter and energy will fall forever towards
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the black hole's singularity.
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However, outside this event horizon material can still
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escape when material comes into contact with the area around the
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black hole, it's scooped up into an accretion disk where immense
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gravitational forces crush and rip it apart, releasing vast
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amounts of energy and material.
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These are guided by powerful magnetic forces into beams
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traveling perpendicular to the accretion disk often at
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superluminal speeds, the most powerful of these beams which
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emerge from super massive black holes millions to billions of
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times the size of their stellar counterparts. And found that the
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centers of most Galaxies form quasars bright enough to be seen
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across the other side of the universe.
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But a subset of accreting stellar mass black holes can
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also launch jets of highly magnetized plasma referred to as
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micro quasars. Now, a report in the journal nature studying a
00:08:20
galactic micro quasar cataloged as GS 1915 plus 105 has
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discovered features in the quasar that have never been
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detected before using the 500 m aperture spherical radio
00:08:33
telescope. In China.
00:08:34
Astronomers have for the first time detected a quasi periodic
00:08:38
oscillation signal in the radio band of the quasar quasi
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periodic oscillation signals are a phenomenon that astronomers
00:08:45
use to understand how stellar systems like black holes
00:08:49
function. And while they've been observed in x rays from micro
00:08:52
quasars, their discovery in radio emissions in the quasar is
00:08:56
unique.
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The study's lead author Wei Wang from Wuhan University says the
00:09:01
quasi periodic oscillation signal had a rough period of
00:09:04
about 0.2 seconds. That's a frequency of about five Hertz.
00:09:09
Now, such a signal doesn't always exist and only shows up
00:09:13
under special physical conditions. The authors were
00:09:16
lucky enough to catch the signal twice once in January 2021. And
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again in June 2022.
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This unique feature may provide the first evidence of activity
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from a jet launched by a stellar mass black hole. Now, under the
00:09:31
right conditions, some black holes in binary systems will
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launch a jet, a mixture of parallel beams of charged
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matter, magnetic material that's moving at close to the speed of
00:09:41
light. The detailed mechanism to induce this temporal modulation
00:09:45
in a relativistic jet hasn't been identified.
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However, one plausible mechanism would involve the jet's
00:09:51
direction regularly changing and then returning to the original
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direction. Once every 0.2 seconds, a misalignment between
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the spin axes of the black hole and its accretion disk could
00:10:02
cause this effect which would be a natural consequence of the
00:10:05
dragging of space time near a rapidly spinning black hole.
00:10:09
What astronomers and physicists refer to as frame dragging. It's
00:10:13
a fascinating prospect this space time still to come,
00:10:19
Houston, we have a problem. A blackout hits the Johnson Space
00:10:23
Center in Houston, Texas. And we look at the giant star, Antares
00:10:27
the second nearest star system to the Sun Barnard star and the
00:10:31
annual Perseids meteor shower, all that and more coming up on
00:10:35
August sky watch.
00:10:52
Well, it was very much a case of Houston. We have a problem when
00:10:55
a power outage disrupted communications between Mission
00:10:59
Control and the crew aboard the International Space Station.
00:11:02
The sudden blackout during work to upgrade other equipment at
00:11:06
the Johnson Space Center prevented mission managers from
00:11:08
sending commands to the space station or talking with the
00:11:11
orbiting crew while the crew worried no danger during the
00:11:15
outage, it still took 90 minutes for backup power to come online.
00:11:20
The on station crew were told of the problem by Russian mission
00:11:23
managers at their control center in Moscow about 20 minutes into
00:11:26
the failure. It's the first time NASA's had to fire up the back
00:11:30
up systems to take control something which should take
00:11:33
place instantaneously when power is accidentally lost.
00:11:37
NASA also maintains a back up control center on the outskirts
00:11:40
of Houston in the event of a hurricane or other disaster
00:11:43
requiring evacuations from the Johnson Space Center.
00:11:47
That mission managers did need to move this time as the lights
00:11:50
and air conditioning kept working because they were on a
00:11:52
different circuit. This is space time and time now to turn our
00:12:11
eyes to the skies and check out the celestial sphere for August
00:12:15
on Skywatch.
00:12:16
August is the eighth month of the year in the Julian Eggo
00:12:19
calendars. It was originally named six Tillerson Latin
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because it was the sixth month of the original 10 month roaming
00:12:26
calendar under Romulus in 7 53 BCE.
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When the year started in March, it only became the eighth month
00:12:33
when January and February were added to the start of the year
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in the year eight BC. It was renamed in honor of the Roman
00:12:39
statesman and military leader Augustus who had achieved
00:12:42
several military victories including the conquest of Egypt
00:12:46
during the month.
00:12:47
Ok. Turning to the heavens and the constellation Scorpius, the
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Scorpion is high overhead this time of year covering almost a
00:12:54
third of the August night skies. At the heart of Scorpius,
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located some 470 light years away is the red super giant
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Antares.
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A light year is a distance of about 10 trillion kilometers.
00:13:08
The distance a photon can travel in a year at 300 kilometers
00:13:11
per second. The speed of light in a vacuum and the ultimate
00:13:14
speed limit of the universe, red super giants have the largest
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diameters of any known star.
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They evolve out of main sequence stars with more than eight times
00:13:24
the mass of the Sun. A main sequence star is a star using
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hydrogen into helium in its core.
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When stars stop fusing hydrogen into helium in their core, the
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balancing act between gravity, pushing a star's mass down
00:13:38
towards the center and energy from nuclear fusion in the core,
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pushing outwards ceases and gravity winds causing the star
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to begin to collapse inwards, crushing the stellar core until
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the increase in pressures and temperatures trigger helium
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fusion.
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At the same time, a shell of hydrogen around the core begins
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to fuse causing the star's outer gases envelope to expand out
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into a bloated giant. And now being further away from the
00:14:03
core, the stellar surface starts to cool down becoming redder in
00:14:07
color. While sunlike stars will become red giants, those that
00:14:11
are far bigger eight times or more the mass of the Sun become
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red.
00:14:14
Super giants, super giants will fuse all their core helium into
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carbon and oxygen within just a few million years, they'll then
00:14:22
begin fusing this core carbon and oxygen into progressively
00:14:25
heavier and heavier elements until they eventually begin to
00:14:28
produce iron in their core.
00:14:30
Now, no star, no matter how massive it is, is big enough to
00:14:34
fuse iron into heavier elements. And so then the star will
00:14:37
collapse catastrophically in what's known as a core collapse
00:14:41
supernova, an explosion bright enough to outshine an entire
00:14:44
galaxy.
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The end result of this core collapse supernova will be the
00:14:49
creation of either a neutron star or a black hole depending
00:14:53
on the progenitor star's mass. The name Antares means rival of
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Mars. And indeed, when they're close together in the sky, they
00:15:00
do look very similar Antares or alpha scorpions.
00:15:04
It's sometimes called, has some 12.4 times the mass and an
00:15:08
incredible 450 times the diameter of our Sun and is one
00:15:12
of the largest known stars in the universe. Antares is so big
00:15:16
that we're a place where the Sun is at the center of our solar
00:15:19
system.
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It would engulf all the inner planets, mercury Venus earth and
00:15:23
Mars, its outer surface would reach almost as far as the orbit
00:15:27
of Jupiter. Antares is a binary system. There's a companion star
00:15:32
orbiting with it called Antares B.
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A massive spectral type B blue white star at least 7.2 times
00:15:38
the mass and 5.2 times the radius of the Sun. It's located
00:15:42
about 224 astronomical units beyond the primary star. An
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astronomical unit is the average distance between the Sun and the
00:15:50
earth about 150 million kilometers or 8.3 light minutes.
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Astronomers describe stars in terms of spectral types, a
00:15:59
classification system based on temperature and characteristics.
00:16:03
The hottest, most massive and most luminous stars are known as
00:16:07
spectral type O blue stars.
00:16:09
They're closely followed by spectra type B, blue, white
00:16:12
stars, N spectral type A white stars, spectra type F, whitish
00:16:17
yellow stars, spectra type G yellow starss. That's where our
00:16:20
Sun fits in spectra type K orange stars and the coolest and
00:16:25
least massive of all stars are spectra type M red stars
00:16:29
commonly referred to as red dwarfs.
00:16:32
Now its spectra classification is further subdivided using a
00:16:35
numeric digit to represent temperature with zero being the
00:16:38
hottest and nine, the coolest and A Roman numeral to represent
00:16:42
luminosity. Now put all that together and our Sun is a
00:16:46
spectral type G two V or G 25 yellow dwarf star.
00:16:51
Also included in the stellar classification system are
00:16:54
spectral types LT and Y which are assigned to failed stars
00:16:58
known as brown dwarves, some of which were actually born as
00:17:02
spectral type M red dwarf stars but became brown dwarves after
00:17:06
losing some of them mass brown dwarfs fit into a category
00:17:09
between the largest planets which are about 13 times the
00:17:12
mass of Jupiter and the smallest spectral type M red dwarf stars,
00:17:16
which are about 75 to 80 times the mass of Jupiter or 0.08
00:17:21
solar masses located near Antares is the spectacular
00:17:26
globular cluster Messier Four or M four.
00:17:28
For short, named after the 18th century French astronomer and
00:17:32
comet Hunter Charles Messier. It's one of a catalog of 103
00:17:36
fuzzy objects which weren't comets and so were of no
00:17:39
interest to messier. And so he made a list of them. So he
00:17:43
didn't waste his time looking at them.
00:17:45
Other astronomers have since added further celestial objects
00:17:47
to the catalog, bringing the turtle to around 110 located
00:17:52
some 7000 light years away.
00:17:54
Messier Four can be seen through a pair of binoculars making it
00:17:57
one of the closest globular clusters to earth globular
00:18:00
clusters are densely packed spheres containing thousands to
00:18:03
millions of gravitationally bounced stars, which it's
00:18:06
thought were either originally all born at the same time in the
00:18:09
same stellar nursery or are the surviving core of Galaxies that
00:18:13
have been cannibalized by larger Galaxies.
00:18:16
They're almost always found orbiting the halo of Galaxies.
00:18:20
The Milky way has about 150 of them and they're all usually
00:18:23
very ancient, some dating back to around 12 billion years
00:18:28
located just below the Sting of Scorpios are two open star
00:18:31
clusters.
00:18:32
M Six and M seven M seven's. The nearer of the two located about
00:18:37
800 light years away. While M Six is a more distant 2000 light
00:18:41
years, open clusters are less densely packed than their
00:18:44
globular cluster counterparts.
00:18:46
With the stars inside them less gravitationally bound and more
00:18:49
prone to drifting away over time. Another open star cluster
00:18:53
in Scorpius is NGC 62 31 located about 6500 light years away just
00:19:00
near the star Zeta Scorpio NGC.
00:19:02
62 31 is a bright open star cluster containing around 100
00:19:07
and 20 stars, including a significant population of highly
00:19:10
luminous super giants, numerous white yellow stars and at least
00:19:14
two wolf rayt stars, wolf rays are extremely luminous evolved
00:19:19
stars reaching the ends of their lives, having run out of
00:19:23
hydrogen for core fusion.
00:19:24
They're no longer on the main sequence and are instead fusing
00:19:28
progressively heavier and heavier elements in their cores.
00:19:31
This causes them to have surface temperatures of up to 200
00:19:35
degrees Celsius.
00:19:36
And such extreme temperatures generate powerful stellar winds
00:19:40
just behind Scorpius is the constellation Sagittarius, the
00:19:44
half man, half horse of Greek mythology. And as we mentioned
00:19:48
in last month's Skywatch, the center of the Milky way galaxy
00:19:51
is found in Sagittarius, roughly 27 light years away.
00:19:55
The name Sagittarius can be traced back beyond the Greeks to
00:19:59
the ancient Mesopotamian Archer, God, Norgle. Sagittarius is
00:20:03
known for its many nebula and clusters more than any other
00:20:06
constellation. One of the largest and brightest is the
00:20:09
globular cluster.
00:20:10
M 22 big enough to be visible to the unaided eye located about
00:20:15
10 light years away near the galactic bulge. M 22 is more
00:20:19
elliptical than most globular clusters. It's located just
00:20:23
south of the ecliptic, the plane in the sky upon which all the
00:20:26
planets orbit the Sun and it contains over 70 stars
00:20:31
covering an area of around 100 light years.
00:20:34
It also contains at least two black holes and is one of only a
00:20:37
handful of globular clusters known to contain planetary
00:20:41
nebulae. The puffed off outer gasses envelopes of dead Sun
00:20:44
like stars located in the sky next to Scorpius in the West and
00:20:49
Sagittarius in the east is the constellation of Eus.
00:20:53
The healer or serpent bearer often portrayed as a snake
00:20:56
curled around a man in Greek mythology. Ofus raises a R from
00:21:01
the dead after he was bitten by Scorpius.
00:21:04
Oye contains several star clusters and other interesting
00:21:07
features including Barnard star. Barnard star is the second
00:21:11
nearest star system to the Sun beaten only by the Artur
00:21:14
Centauri triple star system located some 5.9 light years
00:21:19
away. Barnard's star is a spectral type M red dwarf about
00:21:23
0 times the mass of the Sun.
00:21:26
Our Sun is around 4.6 billion years old at between seven and
00:21:31
12 billion years of age. Barnard's star is considerably
00:21:34
older than the Sun and may be among the oldest stars in the
00:21:37
Milky way galaxy.
00:21:39
It's lost a great deal of rotational energy and its
00:21:42
periodic slight changes in brightness indicate that it's
00:21:46
rotating about once every 130 days. By comparison, our Sun
00:21:50
rotates roughly once every 29 days given its age. Barnard star
00:21:55
was long assumed to be quiescent in terms of stellar activity.
00:21:59
But in 1998 astronomers observed an intense stellar flare,
00:22:03
indicating that Barnard star is indeed a flare star, flare stars
00:22:08
are variable stars. They can undergo unpredictable, dramatic
00:22:11
increases in brightness lasting a few minutes.
00:22:14
It's believed that the flares of flare stars are analogous to
00:22:17
solar flares in the Sun in that they're generated by stellar
00:22:20
magnetic energy stored in the star's atmosphere lying just to
00:22:25
the West of the Scorpion is the constellation Libra. The scales
00:22:29
in Greek mythology, Libra represents the cause of
00:22:32
Scorpius, the Scorpion.
00:22:34
However, the Romans considered Libra a distinct separate
00:22:37
constellation from Scorpius and thought them to be the scales
00:22:40
symbolizing the equinoxes the times of the year in March and
00:22:43
September when the earth gets equal lengths of day and night.
00:22:47
That's because 2000 years ago, when all this was made up, the
00:22:50
Sun moved into Libra at the time of the September equinox. But
00:22:54
due to recession, as the earth's spin axes wobbles in direction,
00:22:57
this point in time has now moved into the adjoining constellation
00:23:01
of Virgo.
00:23:02
If you look to the south and the southern cross, that's the
00:23:05
constellation Centaurus, another half man, half horse mythical
00:23:09
beast, Centaurus was the teacher of many of the Greek gods and
00:23:13
heroes. He was placed among the stars in the heavens after
00:23:17
accidentally being cured by a poison arrow fired by Hercules
00:23:21
close to the point of star nearest the southern cross.
00:23:24
Beta Centauri lies NGC 51 39 Omega Centauri, the largest and
00:23:30
brightest globular cluster in the visible sky because of its
00:23:34
brightness. The ancient Greek mathematician and astronomer
00:23:37
Claudius Tole originally thought Omega Centauri was a star. It
00:23:41
has a diameter of more than 100 and 50 light years and contains
00:23:45
an estimated 10 million stars giving it some 4 million times
00:23:50
the mass of our Sun located some 15 light years away.
00:23:55
Omega Centauri is another very ancient globular cluster around
00:23:58
12 billion years old and it contains many so-called
00:24:02
population two stars. These are the second generation of stars
00:24:06
to have formed and were created directly out of the remains of
00:24:10
the very first stars in the universe. Stars in the core of
00:24:14
Omega Centauri are so crowded. They're estimated to average
00:24:17
only 0.1 light years away from each other.
00:24:20
And that compares to the nearest start Our Sun Proxima Centauri,
00:24:23
which is some 4.2 light years distant, located close to Mega
00:24:28
Centauri in the sky is the giant lenticular galaxy NGC 5128
00:24:34
Centaurus A which we see looking like it's split in half by a
00:24:38
thick band of dust. The galaxy was discovered in 18 26 by
00:24:43
astronomer James Dunlop from his home in what is now the Sydney
00:24:46
suburb of Parramatta.
00:24:48
A time long before the bright lights of a modern city would
00:24:51
make such a discovery impossible. Located some 13
00:24:54
million light years away. Centaurus Sea is one of the
00:24:57
strongest radio sources in the sky and is thought to be the
00:25:01
result of a merger between an elliptical and a spiral galaxy.
00:25:05
It can be easily seen using a pair of binoculars, but you'll
00:25:08
need a telescope to make out its spectacular dust lanes.
00:25:13
August is also the time of the peak of the annual Perseids
00:25:16
meteor shower. The Meteors are the debris trail ejected by the
00:25:20
comet swift tuttle as it travels along its 133 year orbit through
00:25:25
the solar system. As its name suggests, the Perseid's radiant,
00:25:29
that is the point of the sky from which the Meteors appear to
00:25:31
originate lies in the constellation of perseus.
00:25:35
The Perseids are one of the oldest known meteor showers with
00:25:38
early Chinese historical records of its activity going back
00:25:41
almost 2000 years. They're active between July the 17th and
00:25:46
August the 24th with a peak on August 12th with around 60
00:25:50
Meteors an hour being visible.
00:25:52
The Perseids are very bright and fast moving Meteors traveling at
00:25:55
speeds of 59 kilometers per second. They're best seen
00:25:59
between midnight and just before dawn producing long bright
00:26:02
trails and some fireballs. Most Perseids burn up in the
00:26:07
atmosphere at altitudes of over 80 kilometers. They're best seen
00:26:11
from the northern hemisphere.
00:26:12
So for southern hemisphere skywatchers look to the north
00:26:15
with the radiant below the northern horizon, there are two
00:26:19
full moons in August. The first occurred on August the first, it
00:26:23
was a perigee full moon or super moon because it was a bit closer
00:26:27
to the earth than average and consequently appeared slightly
00:26:30
larger.
00:26:31
Although you wouldn't have noticed it in real life. By the
00:26:34
way, this was the fourth super moon in a row and the biggest
00:26:37
and brightest super moon of the year. Now, the farmers' Orman
00:26:41
Act also listed this full moon as a Sturgeon moon named after
00:26:45
North America's biggest fish because large numbers of
00:26:48
sturgeons are found in the Great Lakes this time of year in other
00:26:52
parts of the world.
00:26:53
It's often referred to as a green moon, a corn moon, a les
00:26:56
moon and even a lightning moon. So you've got plenty of names to
00:27:00
choose from. The second full moon of the month will be on
00:27:03
August, the 30th and that will make it a blue moon according to
00:27:06
some definitions.
00:27:08
However, NASA says the traditional definition of a blue
00:27:11
moon refers not to the second full moon of the month, but the
00:27:15
third full moon in a season that has four full moons turning to
00:27:19
the planets now and Venice and Jupiter have both dropped into
00:27:22
the solar glare ending their lengthy rains as evening stars,
00:27:27
mercury remains above the horizon in the western evening
00:27:30
twilight at magnitude zero with Mars six times fainter than
00:27:34
mercury hovering just above it.
00:27:36
On August the ninth, the moon will form a pre dawn conjunction
00:27:40
with Jupiter. And on August 20th, Venus will rise before
00:27:44
dawn becoming the morning star for coming months. On August the
00:27:48
27th, Satin will arrive at opposition its brightest of the
00:27:52
year. This means it'll be directly opposite in the sky
00:27:56
from the Sun, making a spectacular night time
00:27:59
observational target.
00:28:00
Satin now rises at sunset and remains out all night. And on
00:28:05
August, the 30Th Satin will hover just above the full moon
00:28:08
after nightfall and as Satin is at its best right now, it'll be
00:28:12
easy to identify by using the full moon as a guide.
00:28:16
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