Did you know that the Moon's rotation is locked to its orbit around Earth by a bulge of material under the Moon's surface? This material is denser than the rest of the Moon's surface material, and Earth's gravity pulls on it especially strongly. The side of the Moon containing the bulge always faces Earth. We call it the near side and we call the other side, which we never see from Earth, the far side. People often mistakenly use the term "dark side" when referring to the far side of the Moon, forgetting that the far side is fully illuminated by the Sun whenever we see a new moon from Earth.
If we were to look from high above the Earth-Moon system, we would see the Moon rotate once per month with respect to the stars. This is its sidereal ro ...
I learned about something called axial precession in astronomy class several years ago, which is the idea that as something rotates along its axis, it will slowly trace out a cone if the weight of the object isn't equally distributed. In the case of Earth, Earth isn't a perfect sphere as many of us may think it is -- it actually bulges out in the middle enough for it to allow this phenomenon to occur. At the time, all I really took from this concept was how fascinating it is for the north axial pole to move 1° every 72 years from where it is now, and complete one full cycle every 26 000 years. However, I never managed to understand how this concept could fit in to my understanding of why ice ages[1] occur, and why they too follow a specific ...
It's hard to fathom the difficulties our ancestors had to contend with given how our world has advanced with technological sophistication over the past century. We shouldn't, however, underestimate the power of the human-mind, and how everything that was discovered in the past paved the way for the practices used today, especially those used in science.
Of the very first astronomers, the ancient Babylonian were the first to use simple arithmetic to predict the positions of celestial bodies. Evidence reveals that these astronomers, working several centuries B.C.E., also employed sophisticated geometric methods that foreshadow the development of calculus. Historians had thought such techniques did not emerge until more than 1400 years later, ...
Desolate, frozen and black as coal - welcome to the surface of Comet 67P/Churyumov-Gerasimenko. This is one of the closest colour images ever of a comet, taken from just 29 kilometres away by the European Space Agency's Rosetta spacecraft. Rosetta will soon land on this rugged surface.
Sky gazers will be treated to a rare convergence of celestial events on 31 January — a blue moon, a supermoon, and a total lunar eclipse, all in one. The phenomenon, which hasn’t happened since 1866, graces the sky when the second full moon of the month (known as a blue moon) is in its closest position to Earth, making it appear even larger than usual — a supermoon.
The seldom-seen event will be visible in western North America, Asia, Australia, and elsewhere across the Eastern Hemisphere. So, if you’re in one of those lucky locations and want to see an event that’s literally once in a blue moon, here’s your chance.
This image, released by NASA a few days ago, overlays a year's worth of photographs of the Sun, revealing the migration of active regions towards the equator.
Two days ago, I streamed history being made for the first time ever online, and witnessed the Philae lander's touchdown on Rosetta's comet. The journey took 10 years, 6.4 billion kms away from here, and a 7 hour long landing.
Unfortunately, it was an awkward landing where Philae landed approximately 1km away from its intended landing site that currently, one of its 3 legs is not on the surface of the comet and it itself is oriented in a way that no sufficient sunlight is being recieved enough to charge its batteries ever 12 hour rotation.
At the moment, plans to try to "hop" the robot back into a position for enough sunlight are being studied, hopefully in time to execute them before Philae dies out sometime between next Friday and Saturday. ...
At the very top of Venus’s mountains, below a thick layer of clouds, is snow. But not snow as we know it - with some surfaces reaching 480°C, Venus is way too hot for that. So what is this stuff? Researchers have figured out that Venus's heat is vaporising minerals called galena and bismuthinite, causing them to enter the atmosphere as a metallic mist before condensing into a shiny, metallic frost that rains down on the mountaintops.
After a journey spanning nine years and almost 5 billion kilometres, NASA’s New Horizons spacecraft is closer than ever to everyone’s favourite former planet, Pluto. On 14 July 2015, New Horizons is expected to fly within 12,000 km of the lonely cosmic body - about the distance between Seattle and Sydney - zooming through the orbits of its five tiny moons.
Europa, a moon of Jupiter, is a prime candidate for life in our solar system beyond Earth. It contains water and is also the only known solar system body to have plate tectonics.
Here's what Venus would look with water, and without its thick CO2 atmosphere
When we think of Venus, we envision a planet that'd make a great place for hell - fiery red, extremely hot, and toxic. However, a new study makes an argument that Venus may have once been able to support life, until a mysterious resurfacing event took all that away about 700 million years ago.
According to planetary scientist Michael Way from NASA's Goddard Institute for Space Studies, Venus may have had a stable climate for billions of years.
"It is possible that the near-global resurfacing event is responsible for its transformation from an Earth-like climate to the hellish hot-house we see today."
This is a full-disk image of Mars, showing nearly an entire hemisphere of the Red Planet. It was captured this week by India's Mars Orbiter Mission and shows a storm brewing in the north (around the 11 o'clock position).
The Sun, through an H-alpha filter, which captures a narrow band of light containing the frequency of photons emitted when a hydrogen's electron drops from the 3rd energy level to the 2nd.
Before you watch the video (or read the explanation underneath), try answering the question: What causes the seasons on Earth?. You'll be surprised that even the brightest minds – many of whom have been educated at one of the world's leading universities – can have the same misconceptions as everyone else.
Many believe that the Earth's orbit is an exaggerated ellipse, as pointed out by the narrator. Although the Earth’s orbit is elliptical, it is so close to round that Earth’s distance from the Sun does not vary enough to affect the seasons. In fact, its orbit is only 1.7 percentage points from being perfectly round.
Indeed, Earth is closest to the Sun each year on January 4, when it is winter and cold in the Northern Hemisphere. The seasons ...
