Possibly, comets brought water to Earth
To see exactly what is in the comet, it is necessary to analyse its substance with the help of different high sensitive devices, bringing samples to Earth. But aboard a small spacecraft such devices are difficult to place, because the size of the station Stardust 1,7×0,7×0,7 meters – about the same size as the Desk. How to take a sample of matter, flying from the comet’s nucleus at high speed? Space standards Stardust was moving slowly relative to the comet, about one and a half times slower than fly around the Earth artificial satellites. However, even this speed was several times greater than that of the bullet, the station flew over one second 6 km from the Contact of dust particles with the container of solid material at this speed (more than 20 thousand km/h) would have led to their strongest heating and evaporating. The only way to mildly catch and stop these dust particles, turned out to be a trap made of unique material – aerogel, which was established in 1931, but the big distribution has not received. Continue reading
Space flights cause a failure in the immune system of a person
The results of two studies of NASA, recently published in the journal journal of Interferon & Cytokine Research suggest that spaceflight may cause temporary changes in the immune system of crew members who are long time on Board the International Space Station.
Data obtained at an early stage of one of the experiments showed that the distribution of immune cells in the blood of crew members during the flight remained relatively unchanged. However, they found that some cell functions were significantly reduced, while the activity of another cell type, on the contrary, increased. That is, in a sense, the immune system of crew members, it failed.
If the cell activity is suppressed, the immune system cannot adequately react to threats, which can lead to asymptomatic for the virus. If activity is increased, the immune system becomes too sensitive, which can lead to the development of allergic reactions and persistent rashes, as well as reported some of the crew members.
In another study, scientists analyzed blood plasma, measuring the concentration of cytokines – proteins that regulate the immune system. Continue reading
At the end of last week in Ulyanovsk has started an interesting project Simple science. Its initiator is the teacher of UVAU HA Leonid Podymov.
— The main purpose of my lectures is to educate. I would like to tell Ulyanovsk on the latest and most interesting achievements in modern science into simple language so that it is clear even to the unprepared listener, — says the organizer of the “Simple science”.
Leonid physicist by education, so the project is focused mainly on natural Sciences. In particular, the first lecture was devoted to astronomy — or rather, cosmic distances and scale.
— Many people know that, for example, our Solar system is big. But it is actually an ordinary person is unlikely to adequately represent these scales and distances — simply because it is not something to compare. I tried using a few simple techniques to bring clarity in such comparisons, says the teacher.
So, during the speech he invited the audience to spend with him a few thought experiments.
— Let’s imagine that our planet has shrunk to the size of a standard basketball ball whose radius 12.2 centimeters. If we reduce all other razmery accordance with a given scale, we get the following illustrative figures: the Sun will be a ball with radius 13 meters. Continue reading