May 9, Mercury pass across the disk of the Sun – Herald

Today, May 9, 2016, a rare astronomical event will occur – Transit of Mercury. This is one of the most important astronomical events in 2016. Astronomers have been waiting for him ten years, after previous passage happened November 8, 2006. In fact, this so-called astronomical transit – an event at which Mercury will move exactly between the Sun and our planet. On Earth it is visible as a small black dot, slowly move across the solar disk

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While the passage of Mercury is quite rare, but it still happens far more often than the passage of Venus across the disk of the sun. Incidentally, Mercury and Venus are so-called inner planets.

This planet orbits are inside the Earth’s orbit.

From time to time one of the inner planets with the Earth is on one side of the Sun, and the observer can see it against the background of the solar disk. But Mercury is closer to the sun, and for this reason its transit is observed more often.

In the case of Mercury, there are the so-called May and November transits. They are available from 6 to 14 November and from 6 to 10 May, and each has its own frequency. Thus, repeated passage time of May 13 or 33 years, and once in the November 7, 13 or 33 year. That is, the spring transits happen frequently. The last time Mercury was held on the disk of the sun in the spring of 2003, and the next time will do it later, 33 years old, in 2049

But the next November transit will happen much sooner. – November 11, 2019.

For the first time observed the passage of Mercury French astronomer and mathematician Pierre Gassendi November 7, 1631. It is believed that the average Mercury passes through the disk of the Sun 13 times in a century, although this figure from century to century may vary slightly. For example, for the entire XXI century it happens only 14 times. By the way, Venus in this century took place across the solar disk only twice – in 2004 and 2012. And now the next event have to wait until 2117

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Transit May 9 2016 can be seen from most parts of Russia. The exception is the Far East, which at this point is already evening. But the most favorable conditions for observation will develop in the far north in the Murmansk region. There’s passage will be seen from beginning to end, but only in case of good weather conditions

Usually the passage of a planet across the Sun’s disk distinguish several stages:.

1. First contact – the planet Mercury Regarding Sun’s limb. This moment is the beginning of the transit. But the happy owners of narrowband filters may be astronomical if you are very lucky, to observe the planet on the background of prominence even before first contact. In Moscow, this stage will start at 14:. 11.40

2. The second contact – Mercury concerns the solar disk, but is already fully inside. At this point begins the movement of the planets across the solar disk. In Moscow, this step is read in 14:. 14.51

3. High – Mercury is closest to the center of the sun. In Moscow, it will happen in 17:. 55.50

4. Third contact – Mercury regard to the opposition of the solar limb. In Moscow, this phase begins at 20:20. At this time, Sun is low on the horizon. In the capital will actually decline, and surveillance will already be difficult.

5. Fourth contact – Mercury leaves the solar disk completely. In Moscow, the sun will already be below the horizon

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The angular size of Mercury on the sky is very small. Even taking into account that at the time of the passage of Mercury across the disk of the Sun is from us at a minimum distance, its angular size is not to exceed 13 seconds. While the resolution of the human eye is rarely more than 60 seconds of arc. So, unlike the transit of Venus in 2004 and 2012, which can be seen just across the dark glass, you will need an astronomical device – telescope or a telescope. The technique is similar to observations with observations of sunspots. Telescope equipped with a color filter, considering the Sun’s surface. For such observations are best filters that are installed on the telescope lens. This is due to security requirements. The fact that the filters are mounted behind the eyepiece, very hot sunlight. They can weld and even explode, damaging the eye.

But the safest way is the method of observation on the projection screen located behind the eyepiece of the telescope. Only need to remember that when you hover on the sun can not look through the eyepiece.

Typically, a shadow of the telescope or a telescope.

If you put things right, it should be straight, without distortion. For the best picture quality projection screen to shade from direct sunlight. This method is suitable for the simultaneous monitoring of a large group of people – so it is perfectly suited for observing the transit of Mercury

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