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Blazars, Bootids and a Blackout Moon · Star Trails: From Backyard Astronomy to Cosmic Wonder

• 0:07
  Howdy Stargazers, and welcome to this episode
• 0:10
  of Star Trails. Drew here, and I'll be your guide
• 0:13
  to the night sky for the week starting June the
• 0:16
  22nd through the 28th. This week a new moon offers
• 0:20
  up darker skies, Mars dances with Mercury, and
• 0:24
  we look at the weird world of blazars. particle
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  accelerators from galaxies far, far away. Whether
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  you're tuning in from the backyard, the balcony,
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  or just your imagination, I'm glad you're here.
• 0:39
  So find a cozy spot, let your eyes adjust, and
• 0:42
  let's see what the sky holds for us this week.
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  Let's kick things off with the moon. A new moon
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  arrives on June the 25th, which means dark skies
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  all week long. perfect for spotting galaxies,
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  nebula, and those elusive, faint stars. But the
• 1:02
  moon's not taking the whole week off. On the
• 1:05
  morning of June 23rd, look low in the eastern
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  sky before sunrise. You'll catch a slender crescent
• 1:12
  moon hanging just above Venus, which is glowing
• 1:15
  brightly at magnitude negative 4. It should look
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  great through a pair of binoculars. Then, after
• 1:23
  sunset on the 26th and 27th, the crescent moon
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  returns, cozying up with Mercury, and even Castor
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  and Pollux, the twin stars of Gemini, just above
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  the western horizon. Look for this enchanting
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  grouping just as twilight fades. And here's something
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  rare. On the nights of June 28th and 29th, the
• 1:45
  moon slips between Mars and Mercury, with the
• 1:48
  bright star Regulus nearby. If you're in the
• 1:52
  right part of the world, the moon will actually
• 1:54
  pass in front of Mars, which is a lunar occultation,
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  just after midnight, Coordinated Universal Time,
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  on the 30th. Keep in mind, midnight in UTC time
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  is actually the night of the 29th here in North
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  America. For example, for those of us on Eastern
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  Daylight Time, we're four hours behind UTC time.
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  Be sure to use an astronomy app or an online
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  resource like Stellarium Web for the exact time
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  of the occultation in your area. I just checked
• 2:29
  my location and while the moon will come very
• 2:32
  close, it won't be covering Mars from my point
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  of view. Perhaps it will in your area. Even if
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  you don't catch the occultation itself, the trio
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  will make for a brilliant visual cluster. Speaking
• 2:45
  of planets, here's who's on stage this week.
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  Venus is that blazing morning star, best seen
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  in the early dawn, rising in the east. Mercury
• 2:56
  is just starting to show up after sunset, hugging
• 2:59
  the western horizon. Mars is tagging along with
• 3:03
  Regulus, the heart of Leo the lion, and they'll
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  be putting on quite a show in the western sky.
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  Saturn is your pre -dawn companion, glowing steadily
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  in the southeast before sunrise. Jupiter is slipping
• 3:17
  out of view now, setting shortly after the sun.
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  If you're into deep sky observing, this is your
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  week. With no moon to compete, the core of the
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  Milky Way in Sagittarius and Scorpius is at its
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  best. From a dark location, you'll see it stretch
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  across the sky, and tucked inside it, things
• 3:37
  like the Lagoon Nebula, the Trifid, and bright
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  open clusters like NGC 6633n Ophicus are all
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  waiting to be explored. One more thing to watch
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  for, the June Bo 'otids meteor shower peaks around
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  June 28th. This is usually a quiet one, but it's
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  been known to surprise, so keep an eye out for
• 3:59
  slow, graceful meteors drifting through the sky.
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  And for those of you up north, keep your eyes
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  peeled for noctilucent clouds. These shimmering
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  electric blue wisps can appear just after sunset
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  or before sunrise, glowing way up at the edge
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  of space. They're composed of icy dust particles
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  that reflect sunlight even when the sun is well
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  below the horizon. They're most common in summer
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  at high latitudes, and they're as eerie as they
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  are beautiful. This week we're heading into the
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  wild frontier of deep space to meet one of the
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  universe's most extreme objects, the blazar.
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  Now, if you've been listening for a while, you've
• 4:47
  heard me chat about pulsars and quasars before.
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  So, what's a blazar, and how is it different
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  from all these other space -r's? A blazar is
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  a special type of active galactic nucleus. That's
• 5:03
  the energetic heart of a distant galaxy, where
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  a supermassive black hole is actively feeding
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  on gas and dust. Now, when a black hole is gobbling
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  up matter fast enough, it doesn't just sit quietly.
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  The whole area around it heats up and glows with
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  incredible brightness, sometimes outshining the
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  galaxy itself. Some of that material gets caught
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  in magnetic fields and is blasted out of the
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  galaxy's poles in two narrow beams called jets.
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  These are streams of particles and energy being
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  launched at nearly the speed of light. When one
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  of those jets is pointed almost directly at us
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  here on Earth, That's what we call a blazar.
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  These jets are moving so fast, they're categorized
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  as relativistic. That just means they're blasting
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  out at speeds close to the speed of light. At
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  those speeds, the rules of physics get weird.
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  Time slows down, mass changes, and light bends.
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  That's Einstein's theory of relativity kicking
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  in. So when we say a blazar is pointing a relativistic
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  jet at us, we mean we're in the direct line of
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  fire of one of these high -speed energy beams.
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  That makes blazars look incredibly bright and
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  variable to us, even if they're billions of light
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  -years away. Now, here's where things get even
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  stranger. In 2017, scientists using a detector
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  buried deep in the ice at the South Pole called
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  the Ice Cube Neutrino Observatory, and yes, that
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  really is its name, spotted a very special kind
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  of subatomic particle, a neutrino. Neutrinos
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  are often nicknamed ghost particles because they
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  barely interact with anything. Trillions of them
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  are passing through your body right now, and
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  you don't even feel it. They're difficult to
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  detect, but in this case, Ice Cube caught one.
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  And when astronomers traced it back to its source,
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  it lined up with a flaring blazar called TXS
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  0506 plus 056. It's located around the left shoulder
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  of the constellation Orion. This was the first
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  time we'd ever linked a neutrino to a known object
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  outside our galaxy. IceCube isn't a telescope
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  in the traditional sense. It's made up of more
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  than 5 ,000 sensors frozen in a cubic kilometer
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  of Antarctic ice. When a neutrino occasionally
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  hits a molecule of ice it produces a tiny flash
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  of blue light. IceCube watches for those flashes
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  and helps determine the direction the neutrino
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  came from. Other observatories like KM3NET in
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  the Mediterranean are doing the same thing but
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  underwater. These detectors are opening up a
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  new kind of astronomy where we study the universe
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  not just with light, but with particles. This
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  is what astronomers call multi -messenger astronomy.
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  We're not just looking at starlight anymore,
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  we're listening to the universe in new ways through
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  particles, waves, and everything in between.
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  Here's the big picture and why scientists find
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  blazars so fascinating. Blazars are natural particle
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  accelerators. You've probably heard of the Large
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  Hadron Collider, that massive underground ring
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  in Europe where scientists use magnets and superconductors
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  to smash particles together to study what the
• 8:41
  universe is made of. Blazars are doing the same
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  thing, but on a cosmic scale. They're accelerating
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  protons and other particles to energies millions
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  of times higher than anything we can do here
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  on Earth. These particles then travel across
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  the universe, sometimes for billions of years,
• 9:00
  and some of them reach Earth. By detecting these
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  particles, we're learning what's happening in
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  the hearts of galaxies, how black holes interact
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  with their surroundings, and what kind of extreme
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  environments the universe is capable of creating.
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  Somewhere out there in a distant galaxy, a black
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  hole is hurling particles into space at nearly
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  the speed of light, and one of them might just
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  pass silently through you, carrying a message
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  from the edge of the universe, telling us what
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  conditions are like near these black holes, how
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  matter behaves in extreme gravity, and how the
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  most energetic phenomena in the cosmos operate.
• 9:45
  If the stars spoke to you this week or if a question's
• 9:49
  been on your mind, I'd love to hear it. Visit
• 9:51
  our website, StarTrails .Show, where you can
• 9:55
  contact me and explore past episodes. Be sure
• 9:59
  to follow us on Blue Sky and YouTube. Links are
• 10:02
  in the show notes. Until we meet again beneath
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  the stars, clear skies everyone.