The upcoming celestial event of October 2020 will showcase Mars in a grand display. Due to the astronomical phenomenon known as the ‘opposition’ effect, this month Mars will appear significantly larger and brighter than usual. This article will explore the key points about opposition and what makes this Mars opposition particularly special.
Understanding ‘Opposition’ in Astronomy
To grasp the concept of opposition in astronomy, it’s crucial to understand that it refers to the scenario when two celestial bodies align in opposite directions in the sky. For instance, during a full Moon, the Moon is in opposition to the Sun, with the Earth approximately between them. Similarly, a superior planet (i.e., a planet with an orbit farther from the Sun than Earth’s) is in opposition when the Earth passes between it and the Sun.
A planet’s opposition is the perfect time for observation due to its proximity to Earth. As such, the planet appears noticeably brighter in the sky. However, Venus and Mercury, which have smaller orbits than Earth, can never be in opposition to the Sun.
The Phenomenon of Mars Opposition
The Mars opposition occurs when Mars and the Sun occupy directly opposing sides of Earth, forming a straight line. This phenomenon unfolds approximately every 26 months when Earth aligns between the Sun and Mars. In 2020, Mars made its closest approach to Earth on October 6th, with the opposition occurring a week later, on October 13th.
Now, Mars will once again draw near to Earth on December 8th, 2022, at a distance of 62.07 km. It’s essential to note that the closest distance is relative and, therefore, is subject to change. According to NASA, Mars previously made its nearest approach to Earth in 2003 in nearly 60,000 years. The planet will not return to that proximity until 2287.
This shift in orbits is due to the irregular circular shape of Earth’s and Mars’ orbits, which can also alter slightly because of gravitational tugging by other celestial bodies. For example, Jupiter impacts Mars’ orbit.
Significance of Mars Opposition
The Mars opposition serves as a major astronomical event, with Mars set to outshine Jupiter this October. As such, Mars will become the third brightest object—after the Moon and Venus—in the night sky throughout the month.
During this opposition, Mars will be visible to the naked eye as a bright star, and its size will dramatically increase when viewed through a telescope. This improved visibility will allow us to discern more of the planet’s features like dark and light regions, the solar ice caps, and even Mars’ surface.
Sources: IE