16 Interesting facts about Mercury

The nearest neighbor of Sun, Mercury has some peculiar characteristics that make it quite different from other planets in the solar system. Let’s find out some interesting facts about Mercury and it’s unique features.


Image: wikimedia.org

1. Mercury – the smallest planet

The solar systemEarlier Pluto held the record of being the smallest planet. But it has got a new gradation and had been put in the category of Dwarf Planet. So, now Mercury is occupying the position of the smallest planet in our solar system. Mercury’s diameter is only 4,876 kilometers i.e. just about the size of U.S.
Source: space-facts.com

2. Our ancestors knew Mercury!

Unlike some other planets, Mercury had been long known to our ancestors. The earliest known record of Mercury is by Sumerians from 3000 BC.
Source: theplanets.org

3. One Mercury year = 88 days

Mercury's Southern Hemisphere
Mercury’s Southern Hemisphere

On Earth our 1 year comprises of 365 days but on Mercury one year is just 88 days long. Also, on Mercury one solar day is equal to 176 days of Earth.
Source: space-facts.com, image: wikimedia.org

4. Named after messenger of God


Mercury revolves around the sun much more quickly than any other planet. Hence, it was named after the messenger of Roman Gods, Hermes who was also known as Mercury.
Source: planetsforkids.org, image: wikimedia.org


5. Orbit of Mercury

solar-systemMercury revolves around the Sun in an elliptical orbit. The crazy news is that while orbiting, Mercury can go as near as 47 million kilometers to Sun and sometimes as far as 70 million kilometers away from the Sun. 47 million kilometers looks like a very large distance but on astral plane this distance is very short.
Source: space.com

6. Two Mercury?

People of early civilizations believed that there were two different planets instead of the one planet Mercury. This is because they could see Mercury twice a day, once in the morning and then again in the evening. What they didn’t know was that it was the same planet which they were seeing twice. The reason why we can see Mercury twice is that it orbits very quickly around the sun.
Source: theplanets.org

7. Molten Core

Internal Structure of Mercury
Internal Structure of Mercury

After Earth, Mercury has the densest core among all other planets in our solar system. Its core is completely molten and consists of molten iron. The iron content in the core of Mercury is much more than any other planet in the solar system.
Source: space.com, image: wikimedia.org

8. Puny Magnetism or not

MESSENGER SunsideMercury’s magnetic field is just 1 percent of that of Earth. But in 2004 when MESSENGER was sent to Mercury it sent back some astonishing facts which suggests that once millions and millions of years ago Mercury’s Magnetic field might have been as strong as the magnetic field of Earth.
Source: space.com, image: wikimedia.org

9. Wrinkles on Mercury!


Mercury wrinklesJust like human, Mercury too have wrinkles. But the reason for these wrinkles is not old age. It’s because earlier the iron core of Mercury was very hot. Gradually when Mercury started to cool down its core contracted which causing wrinkles to appear on the surface. These wrinkles are named Lobate Scarps and they can be about a mile high and hundreds of miles in length.
Source: space-facts.com, image: wikimedia.org

10. We can see Mercury only once in every 7 years

We can see Mercury only when it crosses the face of the Sun. This phenomenon is called transit and it happens only once in every 7 years. The next time we can see Mercury is on 9 May 2016.
Source: universetoday.com

11. Mercury’s crazy temperature

Mercury temperatureMercury being so close to sun will make anyone think that it has very high temperature. But actually the temperature of Mercury varies greatly during night and day. In the day its temperature may reach up to 427 degree Celsius while at night it can drop down to minus 173 degree Celsius. Trip to Mercury? Pack your summer cloth as well as winter.
Source: coolcosmos.ipac.calteh.edu, image: viralivia.com

12. Mercury’s sodium Tail

mercury's sodium tail
The blue circle in the image is Mercury and the light around is its sodium tail.

Mercury has a tail! It has recently been discovered that Mercury moves with a long comet like tail behind it. This tail is made up of sodium atoms which are pushed off by the intense pressure of Sun’s radiation. Sometimes it looks as if Mercury is wearing a long flapping cape!
Source: space.com, image: nasa.gov

13. Ice on Mercury

North pole of MercuryMercury is the closest planet to Sun which makes it impossible to have ice on its surface. But scientists have found ice on Mercury. The ice had been found in the numerous craters on Mercury where they never receive any sunlight. Also traces of Organics which are building block of life have been found on Mercury’s surface.
Source: universetoday.com, image: wikimedia.org

14. No Hubble telescope for Mercury

Hubble telescope
Hubble telescope

The Hubble Space Telescope which is used to view astral objects far and away cannot be used to view Mercury! The reason is the close proximity of Mercury with the Sun. If Mercury is viewed using the Hubble Telescope then the brightness of Sun can harm the telescope’s electrical components.
Source: planetfacts.org, image: wikimedia.org

15. Too many craters on Mercury

Hun Kal crate on Mercury
Hun Kal crate on Mercury

Earlier astronomers believed that the surface of Mercury is smooth. But in November 1973 when Mariner 10 spacecraft flew by Mercury and took pictures of its surface, it revealed numerous craters. There are so many craters on Mercury that it had gained the position of being the most cratered planet of our solar system.
Source: bobthealien.co.uk, image: wikimedia.org

16. A thin atmosphere

Earlier astronomers used to think that Mercury has no atmosphere but studies have shown that it is enveloped in a thin layer of atmosphere. The unique feature of Mercury’s atmosphere is that it is made up of the atoms from the planet’s own surface. The high heat of Mercury during the day causes the atoms on the surface of this planet to blast off and escape and form its atmosphere. And guess what? Mercury’s atmosphere is constantly replenishing itself.
Source: space.about.com