Closest star to Earth

closest star to earth

Since 1915 we have known about a red dwarf, one of the countless stars that populate the Milky Way and which happens to be the closest to our Sun. Many people wonder what the closest star to earth.

In this article we are going to tell you which star is closest to Earth, what characteristics it has and its importance.

The closest star to Earth

next centauri

In the vast expanse of known galaxies, the Milky Way stands out as a considerable celestial body. Its size is remarkable, dwarfing many others in comparison. With With an estimated minimum of 100 billion stars residing within it, this galaxy has an impressive population. Among these countless luminous entities, the Sun occupies a central place, reigning as the focal point of our own planetary system. Its proximity and familiarity have sparked curiosity about the closest star to our solar companion. Fortunately, scientists have long provided an answer to this intriguing question.

The closest star to our Sun is Proxima Centauri, also known as Alpha Centauri C. Its Latin name translates to "closest to Centauri," which accurately reflects its position within the Centauri constellation. Despite being only four light years from Earth, Proxima Centauri cannot be seen without the help of a telescope. This is due to its classification as a red dwarf, which means it has a relatively low average luminosity and is smaller in size compared to other stars. To put it in perspective, Proxima Centauri is about seven times smaller than our Sun.

The European Space Agency (ESA) has classified Proxima Centauri as a "flaming star", meaning that it is a radiant star that undergoes erratic and striking fluctuations in brightness as a result of its internal convection processes. This fact occasionally causes an increase in the luminosity of the star closest to our Sun.

Characteristics of the closest star to Earth

star close to the sun

According to the space website, Proxima Centauri possesses the features and dimensions commonly associated with red dwarfs, which are the most abundant type of star in our galaxy. Specifically, this celestial entity has a mass equivalent to about 12,5% ​​of the Sun's mass and a diameter that is about 14% of the Sun's diameter.

Proxima Centauri, like other red dwarfs, has one characteristic that sets it apart: its ability to conserve energy, resulting in a longer lifespan. Astronomers studying Proxima Centauri have determined that this star will remain in its middle age for a staggering four billion years. Despite being relatively close in cosmic terms, Proxima Centauri appears tiny even to the powerful Hubble telescope, which highlights the immense scale of the Universe around us.

The closest star system to our Sun is Alpha Centauri, located approximately 4,36 light years away. (or 41,2 billion kilometers) away.

Composed of a trio of stars

red dwarf

The three stars of the Alpha Centauri system They are officially known as Alpha Centauri A (Rigil Kentaurus), Alfa Centauri B (Toliman) and Alpha Centauri C (Proxima Centauri), as designated by the IAU.

The system consists of three stars that are connected by gravitational forces. Alpha Centauri A and Alpha Centauri B, along with a third star called Alpha Centauri C (also known as Proxima Centauri), form a ternary system where the stars orbit a common center of mass.

Naked eye, only the AB system appears as a solitary radiant point in the celestial expanse. Historically, until the 1689th century, this point was considered a solitary star, the brightest in the Centaur constellation. The notion of a binary star, hidden within this luminous point, was initially postulated in XNUMX by Jean Richaud, a French Jesuit, who coincidentally discovered its existence while observing a comet.

Alpha Centauri A, a yellow G-type star, and Alpha Centauri B, an orange K-type star, are a binary system that rotates relative to each other with a period of approximately 80 years (specifically, 79,91 years). During their orbit, these two stars come closest to each other at a minimum distance of 11,2 AU (equivalent to 1670 million kilometers or approximately the average distance between the Sun and Saturn), while their maximum distance is 35,6 AU (approximately 5,3 billion kilometers), similar to the distance between the Sun and Pluto. Because of their comparable masses, they revolve around a central point in space, known as the center of mass, which is equidistant from both stars.

Proxima Centauri, the third star in the system, is also known as Alpha Centauri C because of its orbit around the other two stars. However, there is ongoing debate about its connection to the system, as its large, eccentric orbit raises questions. Despite this, the three stars exhibit equal parallax and proper motion. In 2016, provided more precise measurements of Proxima Centauri's velocity, further supporting the gravitational link between the three stars.

Orbital cycle

If Proxima Centauri were truly connected to the other two stars, its orbital cycle would last several hundred thousand years and it would currently occupy the closest position to our solar system. The average distance between Proxima Centauri and Alpha Centauri AB is approximately 0,06 parsecs, 0,2 light years or 13.000 astronomical units (AU), which is equivalent to 400 times the size of Neptune's orbit. Proxima Centauri, a tiny red star, can only be observed through high-powered telescopes.

Within this star system, there are at least two planets that resemble Earth in size: Alpha Centauri Bb, with a mass about 113% that of Earth, orbits Alpha Centauri B for a period of 3.236 days. Additionally, there is Alpha Centauri Cb, more commonly known as Proxima Centauri b, which orbits Proxima Centauri.

I hope that with this information you can learn more about the characteristics of the star closest to Earth.

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