This Week in Space

Jul 5th 2024

This Week in Space 118

Understanding the Darkness

Hosted by Rod Pyle
Co-Hosted by Isaac Arthur

Dark Matter and Dark Energy

New episodes posted every Friday.
Category: News

For many of us, dark matter and dark energy are two of the least understood areas of cosmology and astrophysics. This week, we invited Alina Kiessling and Jason Rhodes, both Research Scientists at NASA's Jet Propulsion Laboratory, to explain these concepts and their broader implications for cosmology, exoplanet research, and more. Both of them are working on major space telescope projects to research "dark physics," as they will explain. Guest co-host Isaac Arthur asks compelling, comprehensive questions about physics and cosmology while Rod asks things like "is dark energy dangerous?" because, let's face it, someone has to ask the dumb questions. Join us for the fascinating deep dive into dark forces!


  • Chinese rocket startup Space Pioneer accidentally launched a rocket during a static ground test, highlighting the unpredictable nature of rocketry.
  • SpaceX and Jared Isaacman's Polaris Dawn mission, set for July 34th, 2024, aims to conduct the first private spacewalk and set a new orbital altitude record of 870 miles.
  • NASA announced that Boeing's Starliner spacecraft is in good enough condition to stay at the International Space Station for at least 45 days despite ongoing investigations into malfunctioning thrusters and helium leaks.

Main Topic - Understanding the Darkness:

  • Guests Jason Rhodes and Alina Kiessling, both Research Scientists and Astrophysicists at JPL, share their backgrounds and how they met through their shared passion for cosmology.
  • The universe's composition, with dark matter and dark energy making up 95% of its content.
  • Exploring the history of dark matter discovery, from Fritz Zwicky's observations in the 1930s to Vera Rubin's groundbreaking work in the 1960s and 70s.
  • The differences between dark matter and dark energy, their effects on the universe's structure, and the challenges in studying them.
  • The "cosmological crisis" or Hubble tension, which arises from discrepancies between early and late universe measurements.
  • Upcoming space telescope missions, including Euclid, the Nancy Grace Roman Space Telescope, and the Vera Rubin Observatory, are highlighted as crucial tools for advancing our understanding of dark matter and dark energy.
  • The potential need for new physics to explain current observations is explored, with the guests expressing excitement about the possibility of groundbreaking discoveries.
  • Exoplanet research: discussing how the Roman Space Telescope will use microlensing and coronagraphy techniques to detect and study distant worlds.
  • The potential for detecting biosignatures on exoplanets, with a focus on identifying signs of life through spectroscopic analysis.Jason and Alina's advice for aspiring astrophysicists, emphasizing the growing importance of machine learning and artificial intelligence in the field.
  • Finally, a lighthearted discussion of the guests' personal lives and travel experiences, highlighting the balance between their professional and family commitments.

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