Thursday 4 February 2016

Near death: The interval between life and death

http://www.bbc.com/future/story/20150303-what-its-really-like-to-die?ocid=ww.social.link.email

Tuesday 10 November 2015

November 10 is World Science Day

Established by UNESCO in 2001, World Science Day for Peace and Development is celebrated on 10 November each year.

This year's theme is Science for a Sustainable Future; celebrating the UNESCO Science Report

Read more about this on http://www.unesco.org/new/en/unesco/events/prizes-and-celebrations/celebrations/international-days/world-science-day-for-peace-and-development/

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".

Monday 30 March 2015

Americans secretly modified human DNA

Leading US scientists have secretly carried out extensive work by altering the DNA of human embryos, which could lead to the creation of "designer babies". Proponents of these games with the human species considered that the technique could bring a revolution in medicine, allowing scientists to prevent genetic hereditary diseases and significantly reduce the chances of transmission.

However, the treatment has caused controversy, and critics say tampering with human code is dangerous and unacceptable.

It is believed that American scientists have conducted research on the egg cells taken from a woman who suffers from a hereditary disease - ovarian cancer - to explore the possibility of eventual changes in gene expression and thus create an embryo that does not have this hereditary disease. The work was published last year by Luan Yang, a scientist who works in the laboratory of the famous geneticist George Church.


Professor Church is insisted that everything is in the experimental stage and added that the experiments didn't carried out on people. It is believed that a several laboratories working on changing the DNA of human embryos, which means that scientists can attempt to change the personality of people like improving physical predisposition and intellectual abilities.

Professor John Parrington, from Oxford University said that this discovery he had expected, but not so early and it's very effective and beneficial treatment.

However, there are those who warn of the potential dangers of altering the genome of human embryos. It may have unforeseen consequences for future generations and that makes him dangerous and unacceptable.
 

Friday 27 March 2015

Scientists solve the mystery of origin of cells!?

Chemists have experimentally demonstrated just how the building blocks of life ingredients can be created in just a chemical reaction using two ingredients and sunlight.

At its core cell consists of three subsystems: the system for creating sections, which with the help of the lipid content is kept in one place, the metabolic system with catalysts and enzymes and system for copying DNA and RNA.

DNA molecule contains the instructions for making proteins, one of the most important parts of all living organisms. However, the cells may not be copied without a pre-existing DNA and proteins can not be synthesized lipids without enzymes that are based on the proteins.

Problem reminiscent of the story of what is older - the chicken or the egg, now may be solved thanks to the effort of experts.


One of the biggest issues in the study of the origins of life is did the mentioned subsystems formed together and at once or one after the other. A team of Cambridge who runs John Sutherland found it to be a precursor of DNA, RNA, amino acids and lipids can be created from hydrogen cyanide or hydrocyanic acid.

All subsystems could be created spontaneously through chemical reactions driven by the
influence of ultraviolet light. The only thing missing is hydrogen sulfide actually to donate its electron so that it is possible that some minerals containing metals as catalysts part of the process, experts say.  

- The young Earth was a perfect place for such a reactionhydrogen cyanide and hydrogen sulfide in this period were plentiful, as were in meteorites and comets, that bombed our planet in the first few hundred million years - said Sutherland.

It is possible that when these processes were changes that created amino acids and lipids, but in other places.

- It is quite likely that these ingredients separately created "met" after rains united them in the same place - concluded Sutherland.