51³Ô¹Ï

Asteroid approaching Earth
Near-Earth objects are asteroids and comets whose orbit brings them closer than 1.3 astronomical units, or approximately 195 million kilometres, to the Sun.
Photo:Image by ChatGPT/Prompt by Artem Pashchenko

Once-in-a-millennium event

On 13 April 2029, the asteroid 99942 Apophis will pass safely at a distance of about 32,000 kilometers above Earth's surface, within the geostationary orbit, posing no threat to the planet. This extremely close approach will make the asteroid visible to billions of people with the naked eye in the clear night sky.

This will be a once-in-a-millennium event and a unique occasion for a worldwide campaign to raise awareness with regard to asteroids, their scientific and resource value and the potential hazard they pose.

International Year of Asteroid Awareness and Planetary Defence

In 2024, the General Assembly declared 2029 the International Year of Asteroid Awareness and Planetary Defence to take advantage on the close approach of 99942 Apophis and raise global awareness about asteroids.

This initiative aims to highlight the collaborative efforts of the Committee on the Peaceful Uses of Outer Space in mitigating potential hazards from near-Earth objects, while also providing an opportunity for a global educational campaign.

International Asteroid Day

In December 2016, General Assembly adopted resolution , declaring 30 June International Asteroid Day in order to "observe each year at the international level the anniversary of the Tunguska impact over Siberia, Russian Federation, on 30 June 1908, and to raise public awareness about the asteroid impact hazard."

International Asteroid Day aims to raise public awareness about the asteroid impact hazard and to inform the public about the crisis communication actions to be taken at the global level in case of a credible near-Earth object threat.

Background

Near-Earth objects () are asteroids and comets whose orbit brings them closer than 1.3 astronomical units, or approximately 195 million kilometres, to the Sun. NEOs, that are closer than 0.05 astronomical units to Earth's orbit (about 7.5 million kilometers) and larger than about 140 meters in size, represent potentially catastrophic threats to our planet.

According to NASA¡¯s Center for NEO Studies, there are over . The Tunguska asteroid event in Siberia, Russian Federation, on 30 June 1908, was the Earth's largest asteroid impact in recorded history.

On 15 February 2013, a large fireball (technically, called a "superbolide"), traveling at a velocity of 18.6 kilometers per second, entered the atmosphere and disintegrated in the skies over Chelyabinsk. According to NASA, the approximate effective diameter of the asteroid was estimated at 18 meters and its mass at 11,000 tons. The approximate total impact energy of the Chelyabinsk Fireball, in kilotons of TNT explosives (the energy parameter usually quoted for a fireball), was 440 kilotons. The Chelyabinsk event was an extraordinarily large fireball, the most energetic impact event recognized since the 1908 Tunguska blast in Russian Siberia.

The has worked on NEOs for many years, recognising a NEO impact hazard as a global issue demanding an international response. Addressing such a hazard, including the identification of those objects that pose a threat of impact and planning a corresponding mitigation campaign, requires cooperative action in the interest of public safety on the part of the global community.

Building on recommendations for an international response to a near-Earth Object impact threat, endorsed by the Committee on the Peaceful Uses of Outer Space (COPUOS) in 2013, the International Asteroid Warning Network (IAWN) and the Space Mission Planning Advisory Group (SMPAG) were established in 2014.

The uses well-defined communication plans and protocols to assist Governments in the analysis of possible consequences of an asteroid impact and to support the planning of mitigation responses.

is an inter-space agency forum that identifies technologies needed for near-Earth Object deflection, and aims to build consensus on recommendations for planetary defense measures.

Did you know?

  • Like all asteroids, Apophis is a remnant from the early formation of our solar system about 4.6 billion years ago. It originated in the main asteroid belt between Mars and Jupiter.
  • Apophis is about 340 meters in width. It is classified as an S-type, or stony-type asteroid made up of silicate (or rocky) materials and a mixture of metallic nickel and iron.
  • The orbit of Apophis crosses the orbit of Earth. It completes an orbit around the Sun in a little less than one Earth year (about 0.9 years).

International cooperation on planetary defense and protection against asteroids

Apophis¡¯ 2029 Close Approach with Earth

Resources

Resolution

  • International Year of Asteroid Awareness and Planetary Defence, 2029 ()

UN System

Websites

Related Observances

The 51³Ô¹Ï Office for Outer Space Affairs (UNOOSA) works to promote international cooperation in the peaceful use and exploration of space, and in the utilisation of space science and technology for sustainable economic and social development. The Office assists any 51³Ô¹Ï Member States to establish legal and regulatory frameworks to govern space activities and strengthens the capacity of developing countries to use space science technology and applications for development by helping to integrate space capabilities into national development programmes.

 

A rocket with the Moon in the background

On 4 October 1957 the first human-made Earth satellite Sputnik I was launched into outer space, thus opening the way for space exploration. On 12 April 1961, Yuri Gagarin became the first human to orbit the Earth, opening a new chapter of human endeavour in outer space. The race to conquer space in the 21st century has changed significantly, allowing countries such as China, India, Japan, and the European Union, to enter the space race.

 

an abstract illustration of people engaged in an event

International days and weeks are occasions to educate the public on issues of concern, to mobilize political will and resources to address global problems, and to celebrate and reinforce achievements of humanity. The existence of international days predates the establishment of the 51³Ô¹Ï, but the UN has embraced them as a powerful advocacy tool. We also mark other UN observances.