Hubble Explorer
Purpose
Section titled “Purpose”Visualize the expansion of the universe through an interactive Hubble diagram. Plot galaxy recession velocities against distance to see Hubble’s Law in action.
Features
Section titled “Features”Hubble Diagram
Section titled “Hubble Diagram”- Velocity (from redshift) vs. Distance plot
- Interactive zoom and pan
- Hover to see galaxy details
Galaxy Selection
Section titled “Galaxy Selection”- Query SDSS for galaxies in redshift range
- Filter by morphological type
- Select by sky region
Cosmology Tools
Section titled “Cosmology Tools”- Calculate Hubble constant from data
- Show different distance measures
- Compare photometric vs. spectroscopic redshifts
Educational
Section titled “Educational”- Explain Hubble’s Law
- Show historical context
- Interactive “discover the expansion” mode
Data Source
Section titled “Data Source”SDSS SkyServer (direct API queries)
- Millions of galaxies with spectra
- Real-time queries
- See Data Sources
Technical Notes
Section titled “Technical Notes”- Dynamic data loading based on user queries
- D3 for the scatter plot
- Result caching to reduce API calls
- Progressive loading for large queries