Navigation by Pulsar

On the golden record that accompanies the Voyager spacecraft, there is a map showing the location of Earth.  It’s not a road map that you might pull out when navigating a city, but a 3D map showing the location of a star, the Sun, in a populous galaxy.  But just how would this map work? And more importantly, what are the map markers? If you notice the lines at the bottom left of the golden record image, they all intersect at a common center point.  This is the Sun, and the lines extend out showing relative distances to the nearest...

The Ancient Collision That Everyone Saw

The year is 1987, and on February 23rd, three separate neutrino observatories experienced a huge burst in detections. Although initially unsure of their origin, the next day a Supernova was discovered in the Large Magellanic Cloud, a small satellite galaxy of the Milky Way visible in the southern hemisphere.  Known as 1987A, it was the closest supernova observed in centuries, and was observed by astronomers around the world as it brightened and then slowly dimmed.  By combining the visible observations with the neutrino data, scientists learned about how supernovae occur, constrained the mass of the neutrino, and opened a new...

Heavy Metal

Where do the heavy elements on the periodic table come from?  The general answer is from what’s called the r-process of stellar nucleosynthesis.   This translates to ‘rapid neutron capture’ being the method by which most of the elements heavier than Iron are formed on the periodic table.  This process requires immense energy and was originally thought to only occur within core-collapse supernova explosions. “Understanding how heavy, r-process elements are formed is one of hardest problems in nuclear physics,” said Anna Frebel, assistant professor in the Department of Physics at the Massachusetts Institute of Technology (MIT) and also a member of...

The Largest Neutron Star in Existence

Neutron stars are the most extreme objects in the universe that have been proven to exist.  Black holes are very likely, but we’re still not 100% sure about them.  A black hole is like a giant squid in the ocean.  We’re pretty sure they exist, but nobody has caught one.  The neutron star on the other hand is like a blue whale, everybody knows they exist, and they are massive, rare, and beautiful.  Of course, once we know something exists, the next logical step is to figure out how it behaves, to characterize and generalize it, and to identify where it’s...

Where does the Gold come from?

Gold doesn’t come from your local jewelry store, and the Gold rush that occurred in the Yukon territory at the turn of the 20th century is not the source I’m talking about either.  I want to take it further back, to the origins of gold the element.  Similar to the origins of most other elements on the periodic table, it requires an immense amount of energy, such as the nuclear fusion that goes on within a star.  But Gold can not be made by a star’s thermonuclear engine.  Gold requires more energy, as does every other element heavier than Iron.  So...

The Intense Invisible Aurora

Jupiter has aurora.  It’s not surprising since it has a very powerful magnetic field.  It’s only natural that the two largest structures in the solar system, the Sun’s solar wind influence (called the heliosphere)  and Jupiter’s magnetosphere, should be constantly battling. But don’t expect to see Jupiter’s aurora through a backyard telescope.  The result of this battle is far more energetic, producing an aurora invisible to the human eye, one made of X-rays. The Sun constantly blasts charged particles off into space in all directions, assaulting the planets, moons, and other solar system bodies.  It is this blast of solar wind that gives...

Universe Radio on Repeat

Looking at the universe in radio waves is a fascinating sight.  For one, the radio sky is very weak; If you placed your cellphone on the Moon facing back at Earth, it would be brighter than all other radio sources in the entire sky by a factor of a million.  But as with every other part of the electromagnetic spectrum, it has scientific value in studying the sky.  Over the past decade, astronomers have been identifying several Fast Radio Bursts (FRB), short bursts of radio waves from different places in the universe that last for a few short seconds.  These are...

Gamma Rays Point to Pulsars, Not Dark Matter

Gamma rays are the most powerful form of electromagnetic radiation in the universe.  With wavelengths as small at atoms, they usually result from the most powerful interactions known, such as the collision of two particles, or the release of energy from the accretion disk of a black hole.  But there is another potential source of gamma rays that has not yet been confirmed: Dark Matter. The leading candidate for dark matter is the theorized Weakly Interacting Massive Particle (WIMP), though it is not as wimpy as its namesake suggests, making up 5 times as much mass as the visible matter...

Where did the Elements Come From?

The elements that make up our world and our selves, where do they come from? Sure there is plenty of Oxygen in the air, Silicon and Carbon are just lying around, and a bunch of other stuff can be found across our planet.  but where did they come from originally? We know that most of the elements are synthesized within stars, but which ones aren’t? Which ones are made in a lab? The Big Bang gave rise to the first elements Hydrogen and Helium, which eventually clumped together to form the first stars and star producing the heavier stuff.  Lithium,...

A Crabby Pulsar in a Crabby Nebula

The Crab Nebula, as it’s commonly known, is connected to one of the earliest recorded supernova explosions.  In 1054 AD, Chinese Astronomers saw the explosion of this supernova as an incredibly bright star in the sky lasting about two weeks, before fading.  Now, nearly 1000 years later, the explosion is still happening as an expanding shock front rich in heavy elements moves through the interstellar medium.  When the shock front hits dust or gas it is slowed down, giving the resulting nebula a unique shape.  In this case, it looks like a crab. The supernova wasn’t exactly the death of the original...