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...
A newly installed instrument on the European Southern Observatory’s (ESO) Very Large Telescope (VLT) has just taken it’s first images, what we call ‘first light’ in the astronomy world. The instrument, called GRAVITY, uses four different 8m telescopes to perform what we call ‘Baseline Interferometry.’ It is expected that tis is the instrument that will allow humanity to take the first ever direct picture of a black hole. Interferometry is a technique that uses multiple small telescopes all collecting light at a specific wavelength. These telescopes form a line that we call the baseline. The combination of these telescopes and...
Nebula. Collapse. Protostar. Main Sequence. Red Giant. Planetary Nebula. White Dwarf. This is the cycle of life for a star like our Sun. By observing stars across the galaxy, we see snapshots of different points in a star’s life cycle. It’s the same with people; If you went for a walk in a city and observed people for a day, you would see every single stage of a person’s life: Infant, child, adolescent, youth, adult, middle aged, senior. How would you put them in order if you knew nothing about them? With people you might go up and ask them, but with stars we can...
This storm is a monster. It strengthened from a pretty usual category 1 hurricane to the most powerful hurricane the planet has ever seen in less than a day. This strengthening was all due to the warmer-than-usual pacific waters under the influence of el nino. Luckily the storm has weakened since making landfall and is down to a tropical depression (less than a category 1), but it still highlights the fact that warmer oceans and a shifting climate are bringing more extreme weather events our way every year.
In the last few days, we have watched the intricate dance of Venus and Jupiter in the Western sky after sunset. They have tangoed and passed by one another and the world has watched as the best conjunction of the year has come and gone. Don’t forget that even though they appear close in the sky, Venus is actually closer to the Earth than it is to Jupiter. Jupiter is hundreds of millions of kilometers further away than Venus. Today’s APOD is a beautiful shot by Letian Wang combining the proximity of the two planets with the (much further East...
Stars are far apart, especially compared to the everyday distances in human experience. The fastest a human being has ever travelled is just shy of 40 Km/s, and even at that incredible speed it would take 30,000 years to reach the closest star. That is an incredible distance no matter how you slice it. Taking it a step further, most stars in the sky are 20-200 times further away, and that’s just the population of stars we can see. So if we go beyond and talk about galaxies and the distances between them, we are literally talking astronomical quantities. Yet even with...
