Category Space

The dinosaur-killing crash threw huge amounts of debris into the air and caused massive tidal waves to wash over parts of the American continents. There is also evidence of substantial fires from that point in history.

For a long time it was thought that the non-bird dinosaurs died out 65 million years ago.

But Paul explains, ‘The dating of those layers of clay around the world is very accurate – it’s estimated to within a couple of thousands of years.

As originally proposed in 1980 by a team of scientists led by Luis Alvarez and his son Walter, it is now generally thought that the K–Pg extinction was caused by the impact of a massive comet or asteroid 10 to 15 km (6 to 9 mi) wide, 66 million years ago, which devastated the global environment, mainly through a lingering impact winter which halted photosynthesis in plants and plankton.

The blame can’t solely rest on the asteroid. Prior to its crash landing, Earth was experiencing a period of climate change. This was making things harder for life on our planet.

In what is now central India, there was substantial volcanic activity that, although unrelated to the asteroid impact, was causing problems of its own. The resulting lava outcrop is now known as the Deccan Traps.

Paul says, ‘For two million years there was a huge amount of volcanic activity going on, spewing gases into the atmosphere and having a major impact on global climate.

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Every year the world sends satellites and spacecraft to space to improve communications on Earth or to explore planets and moons. But how are these heavy objects sent to space?

A rocket ride

We launch things into space by putting them onto rockets that carry tonnes of propellants (fuel). These propellants give the rocket enough energy to boost away from Earth’s surface. Because of Earth’s gravitational pull the heaviest and the largest satellites or spacecraft need the biggest of rockets with most propellant.

Action and reaction

We now know that we need a rocket to send objects to space, but how does a rocket lift off? The most important idea behind a rocket’s lift off is Issac Newton’s over 300-year-old law, which states that for every action there is an equal and opposite reaction.

If you have seen photos and videos of a rocket launch, you would not have missed seeing exhaust streaming from the bottom of the rocket. This exhaust is the flames, hot gases and smoke that come from burning the rockets propellants. This exhaust pushes out from a rocket’s engine down toward the ground. This is the action force. In response to this action, the rocket begins moving in the opposite direction, lifting off the ground. This is the reaction force.

Let’s keep moving

While the rocket will lift off due to the reactive force of the exhaust, Earth’s gravity will continue pulling it down. So how does the rocket continue moving upwards? When a rocket bums propellants and pushes out exhaust an upward force called thrust is created. To launch, the rocket needs enough propellants to create thrust that is greater than the force of the gravity pulling the rocket down. A rocket needs to speed up to at least 29,000 km/hr and fly above most of the atmosphere in a curved path around Earth. This will ensure that the gravity will not pull it back down.

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The Soviet Union stunned the world on Nov. 3, 1957, with the launch of Sputnik 2. On board the small satellite was a little dog, Laika, the first animal to orbit Earth. However, Laika was not the first animal in space. The United States and the U.S.S.R. had been putting animals atop rockets since 1947.

Laika was a young, mostly-Siberian husky. She was rescued from the streets of Moscow. Soviet scientists assumed that a stray dog would have already learned to endure harsh conditions of hunger and cold temperatures. Laika and two other dogs were trained for space travel by being kept in small cages and learning to eat a nutritious gel that would be their food in space.

The dog’s name was originally Kudryavka, or Little Curly, but she became known internationally as Laika, a Russian word for several breeds of dog similar to a husky. American reporters dubbed her Muttnik as a pun on Sputnik.

Unfortunately, Laika’s trip into space was one-way only. A re-entry strategy could not be worked out in time for the launch. It is unknown exactly how long Laika lived in orbit — perhaps a few hours or a few days — until the power to her life-support system gave out. Sputnik 2 burned up in the upper atmosphere in April 1958.

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The Nobel Prize in Physics was awarded to three astrophysicists Tuesday for work that was literally out of the world, and indeed the universe. They are Roger Penrose, an Englishman, Reinhard Genzel, a German, and Andrea Ghez, an American. They were recognized for their work on the gateways to eternity known as black holes, massive objects that swallow light and everything else forever that falls in their unsparing maws.

Black holes were one of the first and most extreme predictions of Einstein’s General Theory of Relativity, first announced in November 1915. The theory explains the force we call gravity, as objects try to follow a straight line through a universe whose geometry is warped by matter and energy. As a result, planets as well as light beams follow curving paths, like balls going around a roulette wheel.

Einstein was taken aback a few months later when Karl Schwarzschild, a German astronomer, pointed out that the equations contained an apocalyptic prediction: In effect, cramming too much matter and energy inside too small a space would cause space-time to collapse into a point of infinite density called a singularity. In that place — if you could call it a place — neither Einstein’s equations nor any other physical law made sense.

Einstein could not fault the math, but he figured that in real life, nature would find a way to avoid such a calamity.

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It is intriguing that such a small planet can have such a complex collection of satellites. The discovery provides additional clues for unraveling how the Pluto system formed and evolved.

Pluto’s entire moon system is believed to have formed by a collision between two the dwarf planet and another Kuiper Belt Object early in the history of the solar system. The smashup flung material that coalesced into the family of satellites observed around Pluto.

“The moons form a series of neatly nested orbits, a bit like Russian dolls,” said Mark Showalter of the SETI Institute.

The known moons of Pluto are:

• Charon: Discovered in 1978, this small moon is almost half the size of Pluto. It is so big Pluto and Charon are sometimes referred to as a double planet system.
• Nix and Hydra: These small moons were found in 2005 by a Hubble Space Telescope team studying the Pluto system.
• Kerberos: Discovered in 2011, this tiny moon is located between the orbits of Nix and Hydra.
• Styx: Discovered in 2012, this little moon was found by a team of scientists searching for potential hazards to the New Horizons spacecraft Pluto flyby in July 2015.
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Remnants of an ancient water ocean are buried beneath the icy crust of dwarf planet Ceres — or, at least, lingering pockets of one. That’s the tantalizing find presented August 10 by scientists working on NASA’s Dawn mission. 

By far, Ceres is the largest object in the asteroid belt, which girdles the inner planets between Mars and Jupiter. But unlike its rockier neighbors, Ceres is a giant ice ball. It holds more water than any world in the inner solar except for Earth. That knowledge had long led some astronomers to suspect Ceres may have once had a subsurface ocean, which is part of the reason NASA sent the Dawn spacecraft there.

Ceres is the only dwarf planet in the inner solar system, and it locks up one-third of the entire mass in the asteroid belt. Astronomers think Ceres is a protoplanet, the fossilized remains of a world that never fully formed. But its growth was halted before it could become a full planet. Having such a history means Ceres likely holds an early record of our solar system’s primordial past — hence the name Dawn.

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According to International Astronomical Union (IAU), which began meeting in August of 2006, the term Plutoid now applies to Pluto, as well as any other small stellar body that exist beyond the range of Neptune.

Pluto was to these stellar objects what Ceres was to large objects in the asteroid belt – that is to say, comparable in size. Astronomers proposed several names for these objects, but matters did not come to a head until Eris was discovered. This dwarf planet was actually larger than Pluto, 2500 km in diameter, making it twenty-seven percent larger than Pluto.

In the end, the IAU could only resolve this matter by removing Pluto from the list of planets and devising a new category for dwarf planets that could no longer be considered true planets. Plutoid was the result, and now applies to the trans-Neptunian objects of Pluto, Haumea, Makemake, and Eris.

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Jupiter is the fifth planet from our Sun and is, by far, the largest planet in the solar system – more than twice as massive as all the other planets combined. Jupiter’s stripes and swirls are actually cold, windy clouds of ammonia and water, floating in an atmosphere of hydrogen and helium. Jupiter’s iconic Great Red Spot is a giant storm bigger than Earth that has raged for hundreds of years.

The composition of Jupiter is similar to that of the Sun—mostly hydrogen and helium. Deep in the atmosphere, pressure and temperature increase, compressing the hydrogen gas into a liquid. This gives Jupiter the largest ocean in the solar system—an ocean made of hydrogen instead of water. Scientists think that, at depths perhaps halfway to the planet’s center, the pressure becomes so great that electrons are squeezed off the hydrogen atoms, making the liquid electrically conducting like metal. Jupiter’s fast rotation is thought to drive electrical currents in this region, generating the planet’s powerful magnetic field. It is still unclear if, deeper down, Jupiter has a central core of solid material or if it may be a thick, super-hot and dense soup. It could be up to 90,032 degrees Fahrenheit (50,000 degrees Celsius) down there, made mostly of iron and silicate minerals (similar to quartz).

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