Measuring Dark Energy Like a BOSS

When you start to think about the most massive and extreme ‘stuff’ in the universe, you inevitably go to Dark Matter and Dark Energy.  They exist as opposites, one with incredible gravity holding the universe together, and the other a mysterious vacuum energy tearing it apart.  Studying this cosmic tug of war gives astronomers a chance to determine the past and future of the entire universe. To study the immense scale of these two quantities, the Baryon Oscillation Spectroscopic Survey (BOSS) program of the Sloan Digital Sky Survey-III (SDSS) constructed a 3D map of the sky, amounting to a volume...

My Three Suns

Not just the title of an excellent Futurama episode, but now a real place.  A planet has been found orbiting in a triple star system, a surprising find that may be more common than once thought. Astronomers from the University of Arizona used the European Southern Observatory (ESO)’s Very Large Telescope (VLT) in Chile to directly image the new planet as it orbits the brightest star in a triple system 320 light years away, in the constellation Centaurus. Orbits like this are thought to be extremely unstable due to the varying gravitational field in the system. “HD 131399Ab is one of the few exoplanets that...

Falcon Flight to the Galaxy

In the APOD photo from May 14th, it is easy to imagine the rocket launching far away into the galactic disk.  Sadly the rocket can’t traverse the thousands of light years to reach the distant stars, and is restricted to orbiting the Earth. Another beautiful part of this image is the technique involved in producing it.  It required combining two exposures. The first, with low sensitivity to capture the orange rocket trail of the Falcon 9.  The second with high sensitivity and a longer exposure time to capture the faint light of the Milky Way galaxy beyond.  The result is...

Three Nearby Earths

As the search for planets in the galaxy continues, there are two places to focus on: Distant stars with potential large planets, and nearby stars with potential small planets. If we are able to find Earth-like planets orbiting nearby stars, they will be prime targets for future generations to explore. Astronomers have just announced the discovery of three new planets orbiting a star only 40 light years from Earth.  The star is a very small red dwarf, only slightly larger than Jupiter, and even though it’s close to Earth, it can’t be seen with the naked eye or even with a large...

Stellar Snowball

The closest star to the Earth, aside from the Sun, is Proxima Centauri, a small red dwarf star that is part of the Alpha Centauri system, roughly 4 light years away.  If you don’t know light years, the distance is a staggering 37,800,000,000,000 Km.  Beyond that our stellar neighbourhood fills in as you move 20 light years in any direction, and by 100 light years, there are dozens of stars around us.  This gives a stellar density of about 0.14 stars per cubic parsec (a parsec is about 3.26 light years), pretty normal in terms of the number of stars in a given...

Hubble Bubble

Not to be confused with Canadian Gum Hubba-Bubba, Hubble has released a great birthday image for it’s 26th birthday.  I’m a few days late to celebrate, but it’s still a beautiful image. Known as NGC 7653, the Bubble nebula is 8,000 light years distant in the constellation of Cassiopeia.  The reason for this natural bubble shape is that the star just left of center in the image is ionizing a surrounding cloud of Hydrogen with it’s powerful stellar wind.  As electrons and protons recombine at the edges of the bubble, they release an infrared photon that can be clearly seen...

Multiple Ancient Supernovae

If a supernova were to go off somewhere in our galaxy, the minimum safe distance for Earthbound life would be about 50 light years.  Any closer than that, and we would experience an intense blast of high energy radiation and an eventual shower of radioactive particles.  It would be like nuclear bombs were set off all around the Earth, causing little destruction but a lot of radioactive fallout.  Supernovae are incredibly powerful to be able to cause such damage at 50 light years, but even at larger distances, we can see evidence of their effects here on Earth. A team of...

Close, But No FRB

There was a report about a month ago that a Fast Radio Burst (FRB) produced a repeating signal.  This is big news because we really don’t know what causes FRBs, and once they have ended it can be difficult to trace their source.  But a repeating signal means we can pinpoint their origin and potentially figure out their root cause.  It’s no wonder the astronomical community was excited…and skeptical. Most of the FRBs that have been discovered were in archival data – data from past surveys that were given a closer look.  Only a few have been seen in real-time, so when...

The Big Spider

On the outskirts of the Milky Way galaxy, its two major satellites can be seen, the large and small clouds of Magellan.  Both considered irregular galaxies, they are more like swarms of stars, similar to gnats here on Earth.  But even though they lack structure, they are still alive.  The large magellanic cloud contains the single largest active star forming region in the entire local group of galaxies.  This is the Tarantula Nebula. In the core of the tarantula, huge supernova shockwaves blast gas and dust, triggering star formation while forming dense filaments away from the center.  Along the entire...

A Galactic Tale about a Galactic Tail

Galaxy NGC 4569 is a spiral galaxy that is part of the Virgo cluster, around 55 Million light years distant.  Like any other spiral galaxy, we can learn about its motion through the cluster, the properties of its stellar population, and how quickly its converting gas and dust to stars.  But this galaxy has an interesting property, it’s missing a lot of gas.  For years, astronomers have had ideas about where the gas has gone, and with new data from the Canada-France-Hawaii Telescope (CFHT), they now have the answer. The gas is being stripped off of the galaxy, and is now...