Spooky Space, Part 7: Ghoulish Gas Clouds

Happy Halloween everyone! I hope you’ve enjoyed this series of posts.We finish up with some holiday appropriate nebulae, clouds of gas and dust in space that are usually associated with either the birth or death of a star.

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NGC 3242, The Ghost of Jupiter Nebula

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Sharpless 2-136, The Ghost Nebula

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NGC 2080, The Ghost Head Nebula

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Sharpless 2-68, The Death Eater Nebula

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NGC 246, The Skull Nebula

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IC 2118, The Witch Head Nebula

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Spooky Space, Part 6: Vampire Stars

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[Close up of the core of the globular cluster NGC 6397 showing blue stragglers among the red giant stars]

From Dracula to Lestat,  vampires have been a mainstay in popular culture. Seemingly immortal, they survive many times longer than a normal human lifespan by literally sucking the life blood out of their human victims. Astronomers have seen similar behavior in stars called blue stragglers in globular clusters, tightly knit communities of hundreds of thousands to a million stars. They represent some of the oldest stars in our galaxy, so why are there hot blue stars among the dying red giants?

The issue is that hot blue stars have larger masses and hence much shorter lifespans than stars like our sun. So in an old neighborhood like a globular cluster where no new stars are being born, a hot blue star sticks out like a teenager in a retirement community. The solution to this problem seems straight out of an Anne Rice novel.

Despite the fact that the two stars in a binary system form at the same time, they are usually born with different masses and hence die at different times. The heavier star dies first, swelling up to become a red giant. Once this happens, the outer layers of the dying star can be pulled into the smaller star via gravity. This increases the mass of the smaller star, giving it the false appearance of a young and short-lived hot blue star.

But the innocent red giant does have a kind of last laugh on its cannibalistic neighbor. By increasing its mass, the vampire star shortens its lifespan, and will turn into a red giant itself before too long (astronomically speaking).

Spooky Space, Part 5: The Goblin

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[The orbit of The Goblin]

Although it was first discovered in 2015, the extreme dwarf planet 2015 TG387, nicknamed The Goblin, was recently in the news. Astronomers now have a good sense of its orbit, and it’s really out there (literally)!

At about 200 miles wide, The Goblin is only a seventh the diameter of Pluto, but it makes up for its small size with an extreme orbit. At its perihelion (closest approach to the sun), it’s still 7.4 billion miles from the sun, two and a half times farther than Pluto. At its aphelion (most distant point from the sun), it’s an amazing 70 times more distant than Pluto, or more than 200 billion miles!

Such an extreme orbit is a signal that something has gravitationally interacted with The Goblin, and it’s too far from the sun for that “something” to likely have been the giant planets such as Jupiter. It’s possible (note, possible, not definite) that there is a ninth, still undiscovered, planet at least the size of Earth (if not larger) in the outer solar system. If so, then Planet X is haunting us!

Spooky Space, Part 3: Franken-galaxies

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[Three NASA photos of UGC-1382, located about 250 million light years away]

Just as Mary Shelley’s famous creature was constructed of pieces taken from other bodies, Franken-galaxies appear to be amalgams of multiple galactic bodies. One of the most famous is UGC-1382, shown above. The left picture shows what it looks like in regular photo taken by a large telescope. To the eye, it appears like any other elliptical galaxy. However, ultraviolet data (center) and faint visible light (right) show that there is much more to this galaxy that we first suspected, including spiral arms! Not only is the strange galaxy ten times larger than first suspected (and seven times larger than our Milky Way), but it is actually younger on the inside than the outside. Imagine your skin forming and then having your internal organs stuffed inside!

This galaxy is not only inside-out, it is also extremely fragile (in a gravitational sense). The gravity from any nearby galaxies would cause it to fall apart. Luckily for it, UGC-1382 lives in a rather boring cosmic neighborhood.

 

 

Spooky Space, Part 2: Ghostly Neutrinos

 

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[The inside of the MiniBooNE neutrino detector, a perfect name for this time of year!]

The introductory narration to the 1964 episode of The Outer Limits “Production and Decay of Strange Particles”  invokes the “strange world of subatomic particles,” including “anti-matter composed of inside-out material, shadow-matter  which can penetrate 10 miles of lead shielding.” Ten miles of lead? What kind of witchery might this be?

Actually this is a vast understatement. These spooky particles called neutrinos can literally pass through walls of solid lead trillions of miles thick. In the classic paper “The ‘Neutrino’” Hans Bethe and Rudolph Peierls noted that a neutrino could pass through the earth “like a bullet through a bank of fog,”  while John Updike’s poem “Cosmic Gall” compares their effortless travels through our planet to that of “dustmaids down a drafty hall.”  While this means that neutrinos are completely safe, it also poses great difficulties to physicists trying to observe and measure them.

But there is another reason for the neutrino’s dubious reputation; they are produced in large numbers in the supernova explosions of massive stars, serving as celestial harbingers of doom that reach our massive neutrino detectors hours before the actual explosion of the star is visible in our telescopes. In fact, supernovae can be thought of as a “neutrino bombs.” Perhaps this is why in the Star Trek universe, Bajoran wormholes are said to give off elevated numbers of neutrinos whenever something passes through them.

Neutrinos are blamed for all kinds of mischief in popular culture.  In the pilot episode of  Rick and Morty  mad scientist Rick Sanchez takes his grandson Morty Smith on a late-night ride in his space cruiser. Rick has decided to give our planet a clean slate by wiping out the entire human species with a neutrino bomb, with the exception himself, Morty (the new Adam) and Morty’s friend Jessica from math class (Morty’s Eve). In Greg Bear’s novel Foundation and Chaos (based on Isaac Asimov’s Foundation series), the Three Laws of Robotics (which prevent robots from allowing humans – or themselves – to be harmed) are erased from a robot’s positronic brain after he is exposed to a neutrino storm. Neutrinos also trigger the end of the world in the apocalypse blockbuster 2012. Here an abnormally large storm of mutated neutrinos is unleashed from solar flares. In violation of the known laws of physics, these mutant neutrinos heat up the earth’s core and create the impossibly large tectonic shifts that are featured throughout the film. Finally, in the novel Flashforward the cause of the global blackout is tied to the neutrinos from Supernova 1987a interacting with the LHC. Neutrinos might not interact that often with matter, but science fiction seems to think that when they do, it’s very bad.

 

 

 

 

 

 

Spooky Space, Part 1: The Death Comet

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[Asteroid 2015 TB145 aka the Death Comet]

Editor’s note: Each day between now and Halloween we will explore a different example of “spooky space.” Today we feature the so-called Death Comet.

You might have heard something in the news lately about a “Death Comet” that is scheduled to pass by our planet in November. Meet Asteroid 2015 TB145. Yes, that’s right, when this  skull-shaped object was first discovered on October 10, 2015 it was thought to be an asteroid, a hunk of rock about 1300 feet wide. When it passed closest to Earth on Halloween 2015 at about 310,000 miles (a bit farther than our Moon), the above radio telescope image was taken, as well as information on its composition. It was discovered that this trick-or-treating object was actually a trickster – it wasn’t an asteroid at all, but a comet that had spent its supply of what we call volatiles,  frozen materials such as water ice, frozen carbon dioxide (so-called “dry ice”), ammonia and methane, and could no longer create the fuzzy halo (or coma) and tails that are the signature of what most people think of as a comet. Asteroid 2015 TB145  is therefore more correctly a “dead comet.”

Whatever it is, this object will be passing by to say “boo” again this year, approaching 39 million miles away on November 11.

Got Binoculars? Channel Your Inner Galileo

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Have you ever wanted to be Galileo for a day? If you own a pair of binoculars (or a small backyard telescope), now is the time to channel your inner Galileo! Galileo’s 17th century telescopes were very small by today’s standards, with a similar magnification to a pair of common binoculars today. So why not dust off those birdwatching binocs and turn them skyward over the next few weeks?

Our first stop is the planet Venus, now hard to miss in the western sky after sunset. Galileo noticed that Venus shows phases like the moon. The phases won’t be as obvious as shown in the above diagram, so you need to be patient, and hold your binoculars very steady. Use a camera tripod, or try steadying your arms by resting your elbows on a hard surface like a picnic table. Another trick is to hold the binoculars near the far end, where the light enters, rather than putting your hands close to your eyes. This will hold them steadier, because most of the binoculars’ weight is on the far end where the main lenses are.

 

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Our second stop is more towards the south, a “star” that is a little dimmer than Venus, but still rather obvious to the unaided eye. This is Jupiter. Galileo discovered four moons orbiting Jupiter (as shown in a page of his observations reproduced above), which we now collectively call the Galilean moons in his honor. Again, holding the binoculars steady is key here. Watch the moons appear to move relative Jupiter from night to night!

Finally, if the moon is out, don’t forget to train your binoculars in its direction. Galileo studied the craters on the moon, and so can you!

Put on Bohemian Rhapsody, grab your binoculars, and before long you’ll be singing “Galileo, Galileo” as you reproduce the groundbreaking observations of more than 400 years ago. It’s an experience not to be missed!