Scientists have long tried to explain the origin of a mysterious, large and anomalously cold region of the sky. In 2015, they came close to figuring it out as a study showed it to be a “supervoid” in which the density of galaxies is much lower than it is in the rest of the universe. However, other studies haven’t managed to replicate the result.
Low energy efficiency is already a major problem for petrol and diesel vehicles. Typically, only 20% of the overall well-to-wheel energy is actually used to power these vehicles. The other 80% is lost through oil extraction, refinement, transport, evaporation, and engine heat. This low energy efficiency is the primary reason why fossil fuel vehicles are emissions-intensive, and relatively expensive to run.
A volcano is an impressive sight. When they are dormant, they loom large over everything on the landscape. When they are active, they are a destructive force of nature that is without equal, raining fire and ash down on everything in site. And during the long periods when they are not erupting, they can also be rather beneficial to the surrounding environment.
Many of us might respond to this question with a resounding yes. It is easy to think that we all got better rest in those halcyon days when summers were long and hot, winters were snowy and life was a bit less frenetic. But even if this is true about your own sleep, is it really true of people as a whole?
On a clear night, you can make out the band of the Milky Way in the night sky. For millennia, astronomers looked upon it in awe, slowly coming to the realization that our Sun was merely one of billions of stars in the galaxy. Over time, as our instruments and methods improved, we came to realize that the Milky Way itself was merely one of billions of galaxies that make up the Universe.
We don’t want to scare you, but our own Milky Way is on a collision course with Andromeda, the closest spiral galaxy to our own. At some point during the next few billion years, our galaxy and Andromeda – which also happen to be the two largest galaxies in the Local Group – are going to come together, and with catastrophic consequences.
In the summer of 2011, panic gripped a small community in Gatineau, Quebec. Hundreds of small, striped insects were buzzing around a children’s playground. The playground was evacuated and entomologists were called in to establish whether or not the animals were dangerous. The answer was no, but it is easy to see why local residents were concerned. The animals that had taken up residence in the playground were hoverflies, a family of harmless fly species that have built up quite an arsenal of tricks to convince would-be predators that they are dangerous.
How short is an “instant”? Is it a second? A tenth of a second? A microsecond? You might think all of these qualify. What about 100 years? That certainly doesn’t seem like an instant, and to a human being, it isn’t, since we’d be lucky to have a lifespan that long. But to a giant sequoia, say, 100 years is no big deal. And in geological terms it’s practically nothing.
It’s been one of the most astonishing changes in human anatomy. In just one generation, people all over the world have got a lot bigger. Although we’re also gradually getting a bit taller, the really big change has been in body fat. And while much of this is put down to lifestyle, some suggest that “obesity genes” mean it is easy for some people to gain weight and more difficult for them to lose weight
We’ve all had that feeling that somebody is watching us – even if we’re not looking directly at their eyes. Sometimes we even experience a feeling of being watched by someone completely outside our field of vision. But how can we explain this phenomenon without resorting to pseudoscientific explanations like extrasensory perception (or a “sixth sense”)?
As you may recall learning in geology class, the Earth is made up of distinct layers. The further one goes towards the center of the planet, the more intense the heat and pressure becomes. Luckily, for those of us living on the crust (the outermost layer, where all life lives) the temperature is relatively steady and pleasant.
In fact, one of the things that makes planet Earth habitable is the fact that the planet is close enough to our Sun to receive enough energy to stay warm. What’s more, its “surface temperatures” are warm enough to sustain liquid water, the key to life as we know it. But the temperature of Earth’s crust also varies considerably depending on where and when you are measuring it.
Look up at the night sky, and what do you see? Space, glittering and gleaming in all its glory. Astronomically speaking, space is really quite close, lingering just on the other side of that thin layer we call an atmosphere. And if you think about it, Earth is little more than a tiny island in a sea of space. So it is quite literally all around us.
From here on Earth, the Sun like a smooth ball of light. And prior to Galileo’s discovery of sunposts, astronomers even thought it was a perfect orb with no imperfections. However, thanks to improved instruments and many centuries of study, we know that the Sun is much like the planets of our Solar System.
Direction is something we humans are pretty accustomed to. Living in our friendly terrestrial environment, we are used to seeing things in term of up and down, left and right, forwards or backwards. And to us, our frame of reference is fixed and doesn’t change, unless we move or are in the process of moving. But when it comes to cosmology, things get a little more complicated.
When you hear the word desert, what comes to mind? Chances are, you’d think of sun, sand, and very little in the way of rain. Perhaps cacti, vultures, mesas, and scorpions come to mind as well, or possibly camels and oases? But in truth, deserts come in all shapes and sizes, and vary considerably from one part of the world to the next.
Mars’ natural satellites – Phobos and Deimos – have been a mystery since they were first discovered. While it is widely believed that they are former asteroids that were captured by Mars’ gravity, this remains unproven. And while some of Phobos’ surface features are known to be the result of Mars’ gravity, the origin of its linear grooves and crater chains (catenae) have remained unknown.
Humanity has long dreamed of establishing itself on other worlds, even before we started going into space. We’ve talked about colonizing the Moon, Mars, and even establishing ourselves on exoplanets in distant star systems. But what about the other planets in our own backyard? When it comes to the Solar System, there is a lot of potential real estate out there that we don’t really consider.
For millennia, human beings stared up at the night sky and were held in awe by the Moon. To many ancient cultures, it represented a deity, and its cycles were accorded divine significance. By the time of Classical Antiquity and the Middle Ages, the Moon was considered to be a heavenly body that orbited Earth, much like the other known planets of the day (Mercury, Venus, Mars, Jupiter, and Saturn).
