Einstein’s Final Riddle

Why does the Universe expand the way it does? Why does it accelerate? Einstein’s equations offer an explanation of gravity that works on the scale we know, but do they work on the grandest scales of space and time? Humanity now has a way to find out. The General Theory of Relativity predicts the behaviour of gravity, and includes a term known as the cosmological constant.  Einstein added this term to make the universe static and unchanging, as he believed it was.  But when the expansion of the universe was discovered by Edwin Hubble, Einstein regarded it as ‘the greatest blunder...

Mercury Transit with Bonus ISS

Mercury crossed the face of the Sun this past Monday, a relatively rare event that occurs only a dozen (give or take) times a century.  Being able to see it in real time was excellent, but seeing the photos taken by professionals and amateurs alike made the event truly memorable. And look! The International Space Station flew by. Compare this to 2012’s transit of Venus and you get a sense of how much closer to Venus the Earth is than Mercury. In both cases, the most beautiful thing is that you get a sense of just how immense and powerful...

The How and Why of Planet Nine

It hasn’t been found yet – let me make that clear.  But with evidence that it should exist, astronomers are looking more closely at the proposed planet nine and how it might have formed, and how it could have ended up in such a distant orbit. When you start to think about how a planet ten times the mass of Earth could have ended up more than ten times as far from the Sun as Neptune, a few scenarios pop into mind: It was formed in the inner solar system, where interactions with gas giants or another star pulled it out It formed...

Makemake Moon

Hubble just discovered the newest moon in the solar system, a tiny rock orbiting the dwarf planet Makemake, far beyond the orbit of Neptune. The new moon is about 250 Km across, compared to the 1,400 Km wide Makemake.  It orbits in approximately 12 days, and has an edge on orbit, making it difficult to spot. “Our preliminary estimates show that the moon’s orbit seems to be edge-on, and that means that often when you look at the system you are going to miss the moon because it gets lost in the bright glare of Makemake,” said Alex Parker of...

A Ring of Fire

A direct consequence of Einstein’s theory of general relativity, and an observational way to prove it, is gravitational lensing.  It requires a powerful gravitational source to work, such as a galaxy or cluster of galaxies.  It works in a similar way to a lens of glass, where rays of light are bent toward a single source, increasing the brightness.  In this case, instead of glass, the bending of the rays is due to the curvature of space. Light rays coming from the source would otherwise miss Earth, but instead are bent toward us when there is a massive object in front of it.  It’s...

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...

The Flash of a Star’s Death

The most violent single event in the universe is the death of a massive star, a supernova.  We have seen several different types, though the common element is a massive explosion, taking a star hiding amongst the background into an eruption that outshines it’s entire host galaxy.  We have seen the brightness grow and fade over the duration of a supernova event, but we have never seen one just as it’s starting.  Until now. Would you ever have thought that the Kepler space telescope, a planet hunter that continuously observes stars, could see supernovae?  The key is in the words ‘continuously observed.’  By keeping...

Five New Studies of Pluto

It’s been nine months since NASA’s New Horizons spacecraft flew past Pluto.  Time sure does fly.  And even though the spacecraft is moving further from Pluto and Earth, it’s still sending back the massive amounts of data it gathered during closest approach.  As this data is received, the huge team of scientists that are part of the mission use it to characterize Pluto so humanity can begin to understand just how strange the distant dwarf Planet is. Five new papers characterize some of the latest science done on the enigmatic world.  Here’s a quick summary of each: The first paper from...

Edge-On: Good for Planets, Bad for Galaxies

Every time we see amazing photos of galaxies or planetary disks, we can see most of the detail since we see them face on.  But since the orientation of spiral galaxies in the universe is random, there are a plethora of galaxies ignored by image processors since we just can’t see much of the detail.  We can still learn from edge-on spiral galaxies, just not as much as we can from those that are face on. We can see some fascinating dust lanes in the image above, and a ton of detail considering the view, but we don’t know what...

The Ancient Martian Shift

It takes a long time for things to change in the Universe.  Time takes on an entirely different role when it comes to the lives of planets, stars, and galaxies.  A million years in the life of a star or planet is the equivalent of a single day in the life of a human being.  Human lifetimes come and go while stars and planets stay pretty much the same.  However, just like human lives, where many days can build up to an important event, millions of years of lead-up can produce some incredible changes to a planet or star.  New...