gravity

Dark matter may not actually exist – and our alternative theory can be put to the test

 Dark matter may not actually exist – and our alternative theory can be put to the test

Scientists have been searching for “dark matter” – an unknown and invisible substance thought to make up the vast majority of matter in the universe – for nearly a century. The reason for this persistence is that dark matter is needed to account for the fact that galaxies don’t seem to obey the fundamental laws of physics. However, dark matter searches have remained unsuccessful.

NASA used Curiosity’s Sensors to Measure the Gravity of a Mountain on Mars

NASA used Curiosity’s Sensors to Measure the Gravity of a Mountain on Mars

Some very clever people have figured out how to use MSL Curiosity’s navigation sensors to measure the gravity of a Martian mountain. What they’ve found contradicts previous thinking about Aeolis Mons, aka Mt. Sharp. Aeolis Mons is a mountain in the center of Gale Crater, Curiosity’s landing site in 2012.

To Avoid Vision Problems in Space, Astronauts Will Need Some Kind of Artificial Gravity

To Avoid Vision Problems in Space, Astronauts Will Need Some Kind of Artificial Gravity

Ever since astronauts began going to space for extended periods of time, it has been known that long-term exposure to zero-gravity or microgravity comes with its share of health effects. These include muscle atrophy and loss of bone density, but also extend to other areas of the body leading to diminished organ function, circulation, and even genetic changes.

A New Experiment May Finally Reveal the True Nature of Gravity

A New Experiment May Finally Reveal the True Nature of Gravity

Quantum physicists have toiled to no avail for decades in their attempts to subsume gravity (the first cosmological force ever discovered) into quantum physics. A group of researchers recently proposed a new experiment that could redefine nature of gravity, and transform our understanding of the fundamental forces of the universe.

Hubble Captures Massive Dead Disk Galaxy that Challenges Theories of Galaxy Evolution

Hubble Captures Massive Dead Disk Galaxy that Challenges Theories of Galaxy Evolution

By combining the power of a "natural lens" in space with the capability of NASA's Hubble Space Telescope, astronomers made a surprising discovery—the first example of a compact yet massive, fast-spinning, disk-shaped galaxy that stopped making stars only a few billion years after the big bang.

Life on Earth is used to gravity – so what happens to our cells and tissues in space?

Life on Earth is used to gravity – so what happens to our cells and tissues in space?

There’s one force whose effects are so deeply entrenched in our everyday lives that we probably don’t think much about it at all: gravity. Gravity is the force that causes attraction between masses. It’s why when you drop a pen, it falls to the ground. But because gravitational force is proportional to the mass of the object, only large objects like planets create tangible attractions. This is why the study of gravity traditionally focused on massive objects like planets.

Black holes are even stranger than you can imagine

Black holes are even stranger than you can imagine

Our love of black holes continues to grow as our knowledge of these celestial bodies expands. The latest news is the discovery of a rare “middleweight” black hole, a relative newcomer to the black hole family.

How Strong Is The Force Of Gravity On Earth?

How Strong Is The Force Of Gravity On Earth?

Gravity is a pretty awesome fundamental force. If it wasn’t for the Earth’s comfortable 1 g, which causes objects to fall towards the Earth at a speed of 9.8 m/s², we’d all float off into space. And without it, all us terrestrial species would slowly wither and die as our muscles degenerated, our bones became brittle and weak, and our organs ceased to function properly.

Explainer: what is the Great Attractor and its pull on our galaxy?

Explainer: what is the Great Attractor and its pull on our galaxy?

Around four decades ago, astronomers became aware that our galaxy, the Milky Way, was moving through space at a much faster rate than expected. At 2.2-million kilometres an hour, the speed of the Milky Way through the Cosmos is 2,500 times faster than a cruising airliner; 55 times more than the escape velocity from Earth; and a factor of two greater than even the galaxy’s own escape velocity! But where this motion comes from is a mystery.

Explainer: what is microgravity?

Explainer: what is microgravity?

It’s easy to assume that astronauts float in space because they are far away from the Earth’s gravitational force. But look at the moon. It is much further away than the International Space Station, yet it orbits around the Earth because it is perpetually attracted by its gravitational pull. So if the Earth’s gravity can affect the moon, the astronauts cannot be floating because there is no gravity where they are.

Timeline: the history of gravity

Timeline: the history of gravity

Our understanding of gravity has gone through a few permutations, from Newton’s equations through to Einstein’s general relativity. With the discovery of gravitational waves, we look back on how our grasp of gravity has evolved over the centuries.