How to find a planet?
At the end of last year (and the past is 2015; we remind to those who still writes in a diary the old figure), astronomers announced the discovery of the ninth planet of the Solar system. Pluto, as you remember, much to the disappointment of generations, brought up on the fact that in the Solar system 9 planets, it was decided therefore not to consider. It turned out that this is another space dwarf in space a dime a dozen. But let me make one correction: planet UB313 was not open. Scientists just assumed that’s what it is, because watching her is impossible through a telescope. Astronomers are guided only by the reaction of other planets gravity fields, and all that. In the orbits of other planets were found deviations that can be attributed to the fact that somewhere out there in the native system hangs another «child of the Sun». In General, the media, as always, rushed. They say: «the planet could theoretically be,» and they: «So we can write: discovered a new planet. Also, it is inhabited by intelligent life form, then all the bomb! And «Ren-TV» will say that it is inhabited by reptilians».
On this occasion we decided to plunge into the wilds and learn what ways scientists find new celestial bodies.
They are not visible
To detect such alien worlds is difficult, as they are located very close to bright stars, the light which does not allow to see them. Modern tools of astronomy, in particular telescopes, do not allow to see such small and dark objects, like the planets of Earth type. While hardly able to solve only Betelgeuse and the World.
Also, if the exoplanet is located far enough away from its parent star, a small light that it reflects, will be too weak to be detected even with the huge telescope.
Therefore, detection methods of planets can’t be straight. They are indirect, that is, it may well be that the coordinates of the planet slightly off center.
The transit method
Understand that the light of a distant star sometimes gets to see the tiny planet. What should I do? For this you need to calculate the plane of rotation of the planet. If it coincides with the plane containing the observer and interested in the star, during the rotation of the planet around the star, it passes (covers) disc stars. The brightness of the star decreases. It is clear that, given the rarity of planets as such, the probability that the plane of rotation of the planet was successful for us, reduces the ability to detect hundreds of times.
Difficult? Try to explain easier. Scientists measure the change in the luminosity of the star (brighter not brighter – it?) in transit (actually, hence the name of the method). It is not strange, but by means of such purely geometric methods it is possible to determine the physical dimensions of the planet and even its physical properties. The less light, the bigger it is. All more logical than it might seem.
However, the method is extremely inaccurate. First, the brightness of the stars and of itself is non-permanent, and secondly, capturing changes in the brightness of some stars within a few hours over a period of about a year in thousandths of a percent – in itself an incredibly difficult task.
Method for the determination of neutron stars, pulsars and planets
The method is comparatively young and is mainly used to detect the presence of planets near a pulsars – extremely dense rapidly rotating neutron stars.
The point is this: at the time of rotation of planets stars emit intense radiation in the form of rays, which are similar to rays of light of the lighthouse. If the Earth is in the position when it falls the beam of light, earth observers can feel the surge of energy. Thanks to this the pulsations of these stars are called pulsars.
The presence of planets orbiting the stars of a pulsar causes a fluctuation of the light due to the gravitational forces of the planet that affects the schedule of pulsation. Measuring variability of heart rate, you can determine the orbital characteristics and the mass of the planet.
Distant stars act on planets own gravitational forces of the NATO to new members, thus keeping them in orbit (my God, just like in politics), but the gravity of the planets also makes them to be attracted to the star. If the force of gravity level, two celestial bodies revolve around the same point. It’s like two magnets stacked on top of each other and repel each other. This Central point will be in a certain place depending on the mass of both objects.
The star will move away from its center of mass quite a bit, just as deviates from the center of the athlete-thrower when doing the turnover before throwing the hammer. By studying the light emitted by a star, we see light and movement to detect changes in the position of spectral lines. The measurement of these changes allows to determine the approximate mass of the planet. This method of detecting exoplanets is called the Method of radial velocity or Doppler Method.
The method that is used less frequently than the black actors get an Oscar, however, it was discovered on some distant planets and stars. Its essence is simple, as two matches on the table. Take two stars. One star passes in front of another more distant star. The gravitational field closer to the star causes the light of more distant stars how to get around it, sample magnifying lens. In this case you can determine the bursts luminosity of near stars. If the near star exoplanet, its gravity would affect lensing effect.
A sensitive reader will say: «Native manygoodtips.com what do you think about «the Kepler?» What do we say… Good telescope, but not as convenient as it might seem. Although the unit is collected solely for the search of earth-like planets in the zone of stars similar to the Sun, found only five outside the Solar system, and those in question. However, any question and requires confirmation, and it is known to be a matter of time.
Same high sensitivity «Kepler» in both small and large planets enabled him to discover exoplanets, named Kepler 4b, 5b, 6b, 7b and 8b. Called «hot Jupiters» because of the large masses and extreme temperatures, the new exoplanets vary in size, ranging from close to the size of Neptune and ending with the giant like Jupiter. Their orbits range from 3.3 to 4.9 days. Scientists estimate that the surface temperature of the planet ranges from 1500 to 2000 degrees Celsius, it’s your girlfriend, hot molten lava too hot, in order that they could Harbor life in the forms in which we know it.
Now the satellite observes more than 150,000 planets and stars. Let’s hope at least he will be able to find the most protected star, where are the brothers on reason.