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...
What is the difference between a comet and an asteroid? The typical response is that an asteroid is rocky and a comet is icy/gassy. Further than this, asteroids typically orbit closer to the Sun than Neptune, and comets orbit beyond this loose dividing line. But as with everything in nature, there are often exceptions to the rule. C/2014 S3 PANSTAARS is classified as a weakly active comet, originating in the Oort cloud with an orbital period of 860 years. As it approached the Sun, astronomers noticed that it was lacking the characteristic comet tail, resulting from the blast of solar radiation upon approach to the...
Life in the universe is a fascinating topic. The simplest question: Are we alone? It breeds so many deeper and more profound scientific questions, like “How many habitable planets are there?” “How likely is life to develop on any given planet?” and “How long can a civilization survive?” We can’t answer them definitively, but we can narrow it down. The Drake equation, shown above, was first developed by Frank Drake, the head of the Search for Extraterrestrial Intelligence (SETI), in 1961. He took the question of are we alone and made it quantifiable, in a probabilistic way. It lets us...
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...
I’ve written many times about the power of looking at different wavelengths of light to study different properties of the universe. From a visualization standpoint, there are other techniques that give you additional power when imaging. More than just the wavelength of light you’re using to show the detail, you can choose the range of wavelengths to bring forward certain features while suppressing others. The aptly-named spaghetti nebula, shown above, is a great example of this. A supernova remnant that covers the constellations Taurus and Auriga, the nebula is very large in the sky, covering three full moons worth (love that unit...
When could the Moon possibly be brighter than the Sun? The Sun is much bigger, produces energy, and gives all the energy needed for life on Earth. But if you look at the sky in gamma rays, the highest energy photons on the electromagnetic spectrum, you’ll see the Moon more easily than the Sun. Why? The Moon is the brightest gamma ray source in the sky, because it has no atmosphere or magnetic field. Essentially it has no protection from the dangerous cosmic rays that are constantly zipping through space. When they hit the Earth’s atmosphere they create a cosmic...
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...
Even after a decade of interloping among the Saturnian system, the Cassini spacecraft is still doing great science. It helps that there are lots of places to visit, since Saturn has 62 moons and the largest ring system of the gas giants. Arguably the best science has come from Saturn’s largest moon Titan, second largest moon in the solar system (behind Ganymede) and the only moon known to have an atmosphere. Since Cassini has been in orbit around Saturn and it’s system of moons, it’s been revealed that over 1.6 million square kilometers of Titan’s surface are covered in liquid...
A supernova is the death blast of a giant star, far larger than our Sun. Massive stars go out with a bang, outshining entire galaxies, allowing us to see them across the universe. A supernova observed in 2013 occurred in a distant galaxy and took over 30 Million years to reach Earth, where the timing was perfect for us to observe and study it. And now that it’s been studied, the explosion was truly the death of a giant. The supernova, named 2013 ej, was discovered in June 2013 in the galaxy M74 in the constellation Pisces. It was the closest supernova...
Until the recent discovery of gravitational waves, the only ‘sense’ that astronomers had was vision. Granted our ‘vision’ with telescopes is far broader than human eyes, we still need to find ingenious ways to use the precious photons that rain down on Earth. One of the new ways astronomers are using light is to look at what we call a ‘light echo.’ In reality it’s a reflection of starlight. When a new star is forming, it is accompanied by a protoplanetary disk, which will eventually form all the planets of the system. Our own solar system went through this stage 4.5...
