Friday, 17 April 2015

Is the solar system unique in the cosmos?

Solar system works by very simple principles. Small rocky planets are closer to the Sun, gaseous giants are far and between is asteroid belt.

On a broader level, it makes sense. When the sun is "born" enormous energy of young star pushed the lighter elements like hydrogen and helium to the outer edge of the solar system, close yourself leaving only solid materials.

Therefore, one might expect that a similar arrangement of planets can be seen in other systems throughout the universe. However, as we have already discovered many exoplanets, it turned out that this is not the case. Moreover, the arrangement of the planets in the solar system is more the exception than the rule.

Gaseous planets that are far from its parent star are very uncommon. One way to categorize them is to measure the energy they get from their stars.

Hot planets like Mercury and Venus, warm (which may be suitable for life) such as Earth and Mars and cold like Jupiter and distant planets.

In our system, all gaseous planets are "cold", while the case for less than 20 percent of the systems in the universe.

Why is
then Jupiter so far from the Sun? To tell the truth - it's not. 

According to some theories, Jupiter is most likely originated in the distance from the Sun at which the current Mars. Because of the forces that are drawn to, approaching the sun to a distance that is now Venus.
If not for the gravitational interaction with Saturn, probably would be "hot Jupiter", but gradually began to move away from the sun.

Jupiter's journey through the inner solar system explains why we do not have hot gaseous giants in the "neighborhood", but also why we do not have "super-Earth", the planet with a solid core, but much smaller atmospheres, such as the Neptune and many other planets in other systems.

Monday, 13 April 2015

With NASA rocket to Mars in 39 days!

The US space agency NASA is building a new type of rocket propulsion which make people to be able to reach Mars in just 39 days instead of six months, as it has judged!

As a partner in this project, NASA has selected a Texas company, "Ad Astra Rocket Company", which is to develop a drive VASIMR (Variable Specific Impulse Magnetoplasma Rocket). This engine with the help of electromagnetic waves, ionizes and heats fuel gases such as argon or xenon, and turns them into a plasma which are then accelerated by the magnetic field.

Gas is first inserted into the hollow cylinder, in which
using antenna "bomb" with electromagnetic waves which then ejected electrons from atoms and forms a cold plasma consisting of ions and free electrons.

In the second phase, the electromagnet compresses ionized plasma as nozzles compressed gases in conventional rocket engines. The part of the engine known as the ICH, plasma is heated to million degrees Kelvin, which is 173 times higher than the temperature on the surface of the Sun, which is 5,778 Kelvin.

The last part of the engine directs the electrons and ions in the opposite direction of movement of the rocket speed of about 50,000 meters per second!

The new drive can not be used for take-off, or to exit the gravitational "embrace" and the Earth's atmosphere, but the acceleration in interplanetary travel.

- It's a rocket different from all previous - Plasma Rocket - explains Dr. Franklin Chang-Diaz, a former astronaut on "shuttles" and director of "Ad Astra".

New missions in areas closer to the Earth and the Sun will be able to use solar energy, and away from the Sun to Mars to use some more powerful drive, probably nuclear.
In optimal conditions designed rocket to Mars could come for only 39 days. This would significantly reduce the stress and dangers of travel, or exposure to radiation
of Human crew.
NASA has signed a contract with the company of ten million dollars, which envisages the construction of a prototype engine that could run at full power for at least 100 hours. Engine parts have already undergone numerous tests and the first experimental launch is expected in 2016.

Friday, 3 April 2015

How Much Earth Has Changed In 200 Million Years?

Our planet has not always had the seven continents. In the distant geological past there was only one continent - Pangaea, which was divided about 200 million years ago.

Scientists have now reconstructed in detail the transformation of our planet's surface thanks to a new computer model.

On the attached video, you can see a simulation of the movement of Earth's tectonic plates, and each frame is a period of a million years.

"Tectonic plates are changing the speed and direction of movement in a relatively short period of time of about a million years," says Sabin Zahirović,
geo-dynamicist at the University of Sydney, who led the research.

Zahirović and his colleagues are planning to reconstruct the movement of plates before the breakup of Pangaea.

The paper describing this research was published in the journal "Earth and Planetary Science Letters".