Based on the latest data, space, or more accurately, the observable universe, is approximately 13.787±0.020 billion years old.
This age is derived from analyzing data collected by the Planck satellite in 2018. The Planck mission measured the cosmic microwave background (CMB), which is the afterglow of the Big Bang. By studying the patterns and fluctuations in the CMB, cosmologists can determine the age of the universe with remarkable precision.
Here's a breakdown:
- The Big Bang: The prevailing cosmological model suggests that the universe began with the Big Bang, an event that occurred about 13.8 billion years ago.
- Cosmic Microwave Background (CMB): The CMB is the oldest light in the universe, emitted about 380,000 years after the Big Bang when the universe had cooled enough for atoms to form.
- Planck Satellite: The Planck satellite mapped the CMB with unprecedented accuracy. Analyzing this data allows scientists to calculate the universe's age based on how fast it is expanding (the Hubble constant) and the composition of the universe (how much dark matter, dark energy, and ordinary matter it contains).
- Age Determination: The age of 13.787±0.020 billion years represents the time elapsed since the Big Bang, plus the 380,000 years it took for the CMB to be emitted. The ±0.020 billion years represents the uncertainty in the measurement.
While this is the generally accepted age, it's important to acknowledge ongoing research. Different methods for measuring the Hubble constant, such as using distant supernovae, sometimes lead to slightly different age estimates. This discrepancy, known as the Hubble tension, is an active area of investigation in cosmology. However, the Planck data provides the most precise and widely accepted age for the universe.
