Lecture Notes: Understanding Light in Astronomy

Introduction

• Speaker: Dr. Kimberly Arkin
• Host: Matt Schumann, Programming Librarian at Cary Library
• Event Sponsored by: Cary Library Foundation, Tewksbury Public Library, Belmont Public Library
• Keynote Speaker Background:
  • Expert in astronomy visualization
  • Pioneer in 3D printing and extended reality in astronomy
  • Background in molecular biology and NASA's Chandra X-ray Observatory
  • Author of science books, including children's books

Main Topic: Light and the Electromagnetic Spectrum

• Human Vision:
  • Optical light is a small part of the electromagnetic spectrum
  • Comparison: Optical light is to a piano’s middle C as the whole keyboard is to the full spectrum

The Electromagnetic Spectrum

• Radio Waves:
  • Used in MRI for imaging the brain
  • Captured by Earth-based dishes to study phenomena like galaxy jets
• Microwave Light:
  • Used in household microwaves to heat food
  • Studies planet Earth’s moisture levels, useful for post-fire analysis
  • Studies Venus through its thick atmosphere
• Infrared Light:
  • Used in thermometers and fiber optics
  • Studies star formations and the edges of galaxies
• Visible Light:
  • Crucial for human sight
  • Used in microscopy
  • Provides images from telescopes like the Hubble
• Ultraviolet Light:
  • Exposure from the sun, used for sterilization
  • Studies stars and their radiation
• X-ray Light:
  • Used in medical imaging (e.g., at the dentist)
  • Studies high-energy space phenomena like pulsar wind nebulae
• Gamma Rays:
  • Used in cancer treatment, especially brain tumors
  • Studies energetic cosmic phenomena like gamma-ray bursts

Properties and Study of Light

• Properties: Speed, reflection, refraction, absorption, blocking
• Astronomical Applications:
  • Used to study exploding stars, black holes, galaxy collisions
  • Various telescopes and spacecraft are employed to detect different light types

Examples of Light in Astronomy

• M51 (Whirlpool Galaxy):
  • X-ray, ultraviolet, optical, and infrared observations reveal different features
• Cassiopeia A:
  • Supernova remnant analyzed in optical and X-ray light

Data Sonification

• Concept: Translating data into sound for analysis and accessibility
• Examples: Center of the Milky Way, Pillars of Creation, Chandra Deep Field
  • Sonifications used to communicate and study astronomical data

Applications and Impact

• Technological Benefits:
  • Advances in telescope technology benefit Earth-based applications
  • Examples include improved mammograms, digital X-rays, and quality control in supermarkets

Q&A Highlights

• Color Assignment in Astronomy:
  • Not an international standard; usually red for low energies, blue for high
• Auroras:
  • Caused by atomic collisions, visible on other planets

Conclusion

• Speaker's Interest: Passion for astronomy and libraries
• Public Engagement: Books available through libraries and bookstores