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Solar Transit of Mercury

On Monday, November 11, 2019, the University of the Virgin Islands Physics Program hosted its planetarium on the Transit of Mercury. Since Mercury has a different orbit from Earth and are not planar to one another, this phenomenon is rare. This accounts for other planets as well. The next Transits of Mercury will happen in 2032, 2039 and 2049. The transit in 2049 will be as great and visible as this one. The transit in 2032 will not be as great and the one in 2039 will not be very visible to the Virgin Islands.

There were three different sections that each student was able to go to:

  1. The Starlab Planetarium
  2. The Virtual Reality Station
  3. The Telescopes

Dr. Jan Staff, an assistant professor in Physics at the University of the Virgin Islands, went into further explanation as to why the transit of mercury is not common nor fixated. He stated that since the planes of the planets are tilted from one another and that the time it takes each planet to orbit the Sun is not aligned, the years in which the Transit of Mercury will occur are not synchronized.

He discussed the orbits of the four terrestrial planets: Mercury, Venus, Earth, and Mars. An orbit is the curved path in which the planet makes one revolution around the sun. While the earth takes 365.25 Earth days to make an orbit, Mercury takes about 88 earth days. Venus takes 225 earth days to orbit while Mars takes 687 earth days. Eclipses with the moon are more common since the moon completes one full rotation around the Earth approximately within 27 days. When these eclipses and transits from planets and planetesimals occur, light from the Sun is blocked. In the case of the Moon, this will lead to a noticeable drop in the temperature of the atmosphere. Since the planets are farther away from the Moon, a little amount of light is blocked and the change in temperature can be detected by sensitive instruments. Since Venus has a bigger orbit than mars, the transit of Venus is a rarer phenomenon.

Orbiting Planets

Dr. Staff also went into a little more detail about the inner planets. Mercury is a bit dull. When we look at Venus from a satellite, the marbled shape that we are looking at is not the surface but the clouds from the atmosphere. The surface is rocky. Earth is the only planet in our solar system that is known to have life. It is a very colorful planet with an abundance of water. Mars is known as the red planet. The red is the result of oxidated metals that formed rust. Mars has a week atmosphere. The planet has two moons: Phobos and Deimos. These moons are very small.

At the Virtual Reality station, students and employees of the Physics department discussed the formation of the solar system and when into details with the planets. The Sun is 190 times the size of Earth. The formation of the Sun and its planets occurred 4.6 billion years ago. It all started with gas and dust particles. The gas and dust particles collapsed onto each other, forming a circular disk. That circular disk fell into itself at the center and created this massive star: The Sun. With a nuclear fusion, the star formed, pushing all of the particles into space. The remaining dust clumped onto one another, gradually forming the 8 planets of our solar system as well as other planetesimals.

Virtual Reality Station

Mercury is the smallest planet of the solar system. Since it is the closest to the Sun, it is the second hottest planet. Despite being the second closest planet to the Sun, Venus has the highest temperature due to its very thick atmosphere which has a very strong greenhouse effect. It is hotter than Mercury, the closest planet to the Sun. The third planet is Earth. Even though the Earth is 150 million kilometers from the Sun, it takes 8 minutes for the Sun's light to reach Earth. Mars is the fourth Planet. Mars' atmospheric conditions are 38 percent similar to that of Earth. According to theorists, Mars would be considered our second home if anything were to happen to Earth.

After our four terrestrial planets, we have our outer gas giants: Jupiter, Saturn, Uranus, and Neptune. All four of this planets have rings. However, Saturns' rings are very visible as they are made mostly of ice that reflects the Sun's light; the rings of the other gas giants are made of rocky material that do not reflect light. Therefore, the rings on the other gas giants are not so visible. Jupiter is well known for its marbled look and a giant storm in its atmosphere called the Great Red Spot. Uranus is the only planet known for its irregular rotation. Neptune is the farthest and coldest planet, dropping to temperatures as low as -360 Fahrenheit.

At the telescopes, people were able to view the transit of Mercury for themselves between the hours of 11 am - 2 pm AST. Mercury was seen as a tiny, black dot in that gradually moved in front of the Sun.

Transit of Mercury