Mediaspace scheduled maintenance: Aug 25, 2026 07:00 - 12:00 AM. During this time, videos will be temporarily unavailable. Check status updates.

Lecture

Asteroids and Comets Collision Threats

Description

This lecture covers the potential threats posed by asteroids and comets colliding with Earth, including historical events like the Cretaceous-Paleogene extinction and the Chelyabinsk meteor impact. It also discusses concepts such as the 'Gravity tractor' for altering asteroid orbits.

In MOOC

Space Mission Design and Operations

Official source

Ontological neighbourhood

Astronomy

Planetary science: Atmosphere

Related concepts (30)

Chelyabinsk meteor

The Chelyabinsk meteor was a superbolide that entered Earth's atmosphere over the southern Ural region in Russia on 15 February 2013 at about 09:20 YEKT (03:20 UTC). It was caused by an approximately diameter, near-Earth asteroid that entered the atmosphere at a shallow 18.3 ± 0.4 degree angle with a speed relative to Earth of 19.16 ± 0.15 kilometres per second (69,000 km/h; 42,690 mph). The light from the meteor was briefly brighter than the Sun, visible as far as away.

Impact event

An impact event is a collision between astronomical objects causing measurable effects. Impact events have physical consequences and have been found to regularly occur in planetary systems, though the most frequent involve asteroids, comets or meteoroids and have minimal effect. When large objects impact terrestrial planets such as the Earth, there can be significant physical and biospheric consequences, though atmospheres mitigate many surface impacts through atmospheric entry.

Asteroid

An asteroid is a minor planet—an object that is neither a true planet nor a comet—that orbits within the inner Solar System. They are rocky, metallic or icy bodies with no atmosphere. Sizes and shapes of asteroids vary significantly, ranging from 1-meter rocks to a dwarf planet almost 1000 km in diameter. Of the roughly one million known asteroids the greatest number are located between the orbits of Mars and Jupiter, approximately 2 to 4 AU from the Sun, in the main asteroid belt.

Asteroid belt

The asteroid belt is a torus-shaped region in the Solar System, centered on the Sun and roughly spanning the space between the orbits of the planets Jupiter and Mars. It contains a great many solid, irregularly shaped bodies called asteroids or minor planets. The identified objects are of many sizes, but much smaller than planets, and, on average, are about one million kilometers (or six hundred thousand miles) apart. This asteroid belt is also called the main asteroid belt or main belt to distinguish it from other asteroid populations in the Solar System.

Meteor shower

A meteor shower is a celestial event in which a number of meteors are observed to radiate, or originate, from one point in the night sky. These meteors are caused by streams of cosmic debris called meteoroids entering Earth's atmosphere at extremely high speeds on parallel trajectories. Most meteors are smaller than a grain of sand, so almost all of them disintegrate and never hit the Earth's surface. Very intense or unusual meteor showers are known as meteor outbursts and meteor storms, which produce at least 1,000 meteors an hour, most notably from the Leonids.

Related lectures (32)

Astrophysical Objects: Static Systems

Explores spherically symmetric and static astrophysical objects, including black holes and the modeling of matter.

Solar System: Satellite Swarms and Asteroids

Explores satellite swarms, near-Earth asteroids, and the need for international cooperation in space.

Laws of Mechanics and Space Environment MOOC: Space Mission Design and Operations

Covers the laws of mechanics, space environment, and space debris observation.

Introduction to Space Infrastructures: Overview and Enablers MOOC: New Space Economy

Introduces space assets, economy enablers, and supply chain impact.

Hayabusa and Hayabusa 2 MOOC: Space Mission Design and Operations