Kepler-78b

Definition

Kepler-78b is an exoplanet that orbits the star Kepler-78, located approximately 400 light-years from Earth. It is one of the smallest exoplanets ever discovered, with a radius only slightly larger than that of Earth, making it a potentially rocky, terrestrial-like planet.

5 Must Know Facts For Your Next Test

1. Kepler-78b has a mass approximately 1.69 times that of Earth, making it one of the most Earth-like exoplanets discovered to date.
2. The planet orbits its host star, Kepler-78, at a distance of only 1.1 million miles, or about 1/30th the distance between Earth and the Sun.
3. Kepler-78b completes an orbit around its star in just 8.5 hours, making it one of the shortest-period exoplanets known.
4. The extreme proximity of Kepler-78b to its star results in a surface temperature estimated to be around 2,000 degrees Celsius (3,600 degrees Fahrenheit).
5. The discovery of Kepler-78b has provided valuable insights into the formation and evolution of rocky, Earth-like planets in our galaxy.

Review Questions

• Describe the key characteristics of the exoplanet Kepler-78b and explain how it relates to the formation of terrestrial planets.
  • Kepler-78b is an exoplanet that is remarkably similar to Earth in terms of its size and mass, making it one of the most Earth-like planets discovered outside our solar system. It orbits its host star, Kepler-78, at an extremely close distance of just 1.1 million miles, which results in a scorching surface temperature of around 2,000 degrees Celsius. The discovery of Kepler-78b has provided valuable insights into the formation and evolution of rocky, terrestrial-like planets, as its characteristics suggest that Earth-sized planets can form in close proximity to their host stars, challenging previous models of planet formation.
• Analyze the significance of the Kepler-78b discovery in the context of our understanding of exoplanet detection and characterization.
  • The discovery of Kepler-78b is significant because it demonstrates the capabilities of the transit method, which was used to detect this exoplanet. The transit method involves observing the periodic dimming of a star's brightness as a planet passes in front of it, allowing astronomers to infer the presence and characteristics of the exoplanet. The fact that Kepler-78b is one of the smallest exoplanets ever discovered, with a radius only slightly larger than Earth's, highlights the increasing precision and sensitivity of exoplanet detection techniques. Furthermore, the detailed characterization of Kepler-78b's mass, radius, and orbital properties has provided valuable insights into the formation and evolution of rocky, Earth-like planets beyond our solar system, which is a key focus of exoplanet research.
• Evaluate the potential implications of the Kepler-78b discovery for the search for habitable, Earth-like exoplanets and the broader quest to understand the diversity of planetary systems in the universe.
  • The discovery of Kepler-78b, with its remarkable similarity to Earth in terms of size and mass, has significant implications for the search for habitable, Earth-like exoplanets. While the extreme proximity of Kepler-78b to its host star makes it inhospitable for life as we know it, the fact that such a small, terrestrial-like planet can exist in a close-in orbit challenges previous models of planet formation and suggests that Earth-sized planets may be more common in the universe than previously thought. This, in turn, raises the possibility that some of these planets may exist in the habitable zones of their host stars, where liquid water could exist on the surface, potentially supporting the development of life. The Kepler-78b discovery, along with the growing catalog of exoplanets, also highlights the incredible diversity of planetary systems in the universe, which is a key focus of ongoing exoplanet research and a crucial step in our understanding of the origins of life beyond Earth.

Related terms

Exoplanet:

A planet that orbits a star other than the Sun, located outside our solar system.

Terrestrial Planet: A planet that is primarily composed of solid rock, similar to Earth, Venus, Mars, and Mercury.

Transit Method:

A technique used to detect exoplanets by observing the periodic dimming of a star's brightness as a planet passes in front of it.