Adventures of an asteroid hunter | Carrie Nugent
The Formation of Asteroids
This section introduces the concept of asteroids and their formation in the early days of the solar system.
Asteroids: Ancient Cosmic Neighbors
- Asteroids are remnants from the early days of the solar system, formed over four billion years ago during planet formation.
- They are composed of metallic crystals that can only form in space where molten metal cools extremely slowly.
- Asteroids are our oldest and most numerous cosmic neighbors. They orbit around the Sun, with some swinging close to Earth's orbit.
Mapping Near-Earth Space
- Scientists worldwide are actively searching for near-Earth asteroids, discovering new ones every day and steadily mapping near-Earth space.
- NASA plays a significant role in funding this work.
- Last year alone, 1,556 near-Earth asteroids were discovered, adding to a total count of 13,733 known near-Earth asteroids. Their paths around the Sun can be predicted with precision for many years.
Predicting Asteroid Paths
This section highlights scientists' ability to predict asteroid paths with remarkable precision.
Incredible Precision in Path Prediction
- Scientists at the Jet Propulsion Laboratory accurately predicted the path of asteroid Toutatis within 30 kilometers four years in advance. Toutatis traveled 8.5 billion kilometers during those four years, showcasing a fractional precision of 0.000000004.
Unexpected Encounters with Asteroids
This section discusses unexpected encounters with asteroids and their potential impact on Earth.
Chelyabinsk Meteor Event
- Three years ago today (at the time of the talk), a small asteroid exploded over Chelyabinsk, Russia. It was approximately 19 meters across, causing significant damage.
- Objects of similar size hit Earth approximately every 50 years.
The Impact of Large Asteroids
- 66 million years ago, a much larger asteroid impact caused a massive extinction event, leading to the loss of 75% of plant and animal species, including dinosaurs. This asteroid was about 10 kilometers across.
- Visualizing the scale: A rock that enormous would just graze the wingtip of an airplane resting on the ground, with its width taking one full minute for a plane to fly past it.
Asteroid Threat Awareness
This section emphasizes the growing awareness and efforts to study asteroids as potential threats to our planet.
Recognizing Asteroids as Threats
- In recent decades, asteroids have been recognized as credible threats to Earth's safety. Extensive efforts are underway to discover and catalog these objects.
- NASA's NEOWISE telescope has been repurposed for asteroid discovery and study, providing valuable thermal infrared observations that can detect even dark asteroids difficult to spot with other telescopes.
The Responsibility to Search
- Discovering near-Earth asteroids is crucial for our species' survival. As the only species capable of understanding calculus and building telescopes, it is our responsibility to continue searching for these objects and potentially divert any hazardous ones in advance.