Redshift and the Expanding Universe
Observe galaxies receding from Earth. Their light spectra are shifted towards the red end, indicating they are moving away. Faster moving galaxies exhibit a greater redshift.
Click a galaxy to view its spectrum, then click "Record Data".
Hubble's Law Data
| Galaxy | Distance (Mpc) | Velocity (km/s) |
|---|
Composition of Matter
The Big Bang Theory predicts that the early universe was hot and dense enough for nuclear fusion to occur for a brief period. Big Bang Nucleosynthesis created mostly Hydrogen (~75% by mass) and Helium (~25%), with trace amounts of Lithium. Stars later fused heavier elements.
Analysis Status
Matter Distribution (By Mass)
Cosmic Microwave Background (CMB)
The CMB is the remnant radiation from the hot, dense early universe. As the universe expanded, this radiation cooled and its wavelength stretched into the microwave spectrum we observe today at ~2.7 Kelvin.
Observable Universe Model
Radiation Spectrum Peak
Peak Wavelength: 970 nm (Infrared)
Note: As the universe expands, the peak wavelength shifts from infrared to microwave, and the temperature drops according to Wien's displacement law.