Apophis: a European space mission gets up close with an asteroid set to brush by Earth

The European Space Agency has fixed nan go-ahead for first activity connected a ngo to visit an asteroid called (99942) Apophis. If approved astatine a cardinal gathering adjacent year, nan robotic spacecraft, known arsenic nan Rapid Apophis Mission for Space Safety (Ramses), will rendezvous pinch nan asteroid successful February 2029.

Apophis is 340 metres wide, astir nan aforesaid arsenic nan tallness of nan Empire State Building. If it were to deed Earth, it would origin wholesale destruction hundreds of miles from its effect site. The power released would adjacent that of tens aliases hundreds of atomic weapons, depending connected nan output of nan device.

Luckily, Apophis won’t deed Earth successful 2029. Instead, it will walk by Earth safely astatine a region of 19,794 miles (31,860 kilometres), astir one-twelfth nan region from nan Earth to nan Moon. Nevertheless, this is simply a very adjacent walk by specified a large object, and Apophis will beryllium visible pinch nan naked eye.

Nasa and nan European Space Agency person seized this uncommon opportunity to nonstop abstracted robotic spacecrafts to rendezvous pinch Apophis and study much astir it. Their missions could thief pass efforts to deflect an asteroid that threatens Earth, should we needed it successful nan future.

The threat from asteroids

Some 66 cardinal years ago, an asteroid nan size of a mini metropolis deed Earth. The effect of this asteroid brought astir a world extinction arena that wiped retired nan dinosaurs.

Earth is successful changeless threat of being deed by asteroids, leftover debris from nan statement of nan Solar System 4.5 cardinal years ago. Located successful nan asteroid loop betwixt Mars and Jupiter, asteroids travel successful galore shapes and sizes. Most are small, only 10 metres across, but nan largest are hundreds of kilometres across, larger than nan asteroid that killed nan dinosaurs.

Artist’s belief of Apophis.
Nasa

The asteroid loop contains 1-2 cardinal asteroids larger than a kilometre crossed and millions of smaller bodies. These space rocks consciousness each other’s gravitational pull, arsenic good arsenic nan gravitational tug of Jupiter connected 1 broadside and nan soul planets connected nan other.

Because of this gravitational tug-of-war, each erstwhile successful a while an asteroid is thrown retired of its orbit and hurtles towards nan soul Solar System. There are 35,000 specified “near-Earth objects” (Neos). Of these, 2,300 “potentially hazardous objects” (PHOs) person orbits that intersect Earth’s and are ample capable that they airs a existent threat to our survival.

Do not spell gentle into that bully night

During nan 20th century, astronomers group up respective surveys, specified arsenic Atlas, successful bid to observe and study hazardous asteroids. But discovery is not enough; we person to find a measurement to take sides Earth against an incoming asteroid.

Blowing up an asteroid, arsenic depicted successful nan movie Armageddon, is nary use. The asteroid would beryllium surgery into smaller fragments, which would support moving successful overmuch nan aforesaid direction. Instead of being deed by 1 ample asteroid, Earth would beryllium deed by a swarm of smaller objects.

The preferred solution is to deflect nan incoming asteroid distant from Earth truthful that it passes by harmlessly. To do so, we would request to use an outer unit to nan asteroid to nudge it away. A celebrated thought is to occurrence a projectile astatine nan asteroid. Nasa did this successful 2022, erstwhile a spacecraft called Dart collided pinch an asteroid. Before we do this retired of necessity, we person to understand really different types of asteroids would respond to specified an impact.

Apophis, Ramses, and Osiris-Apex

Apophis was discovered successful 2004. The asteroid passed by Earth connected December 21, 2004 astatine a region of 14 cardinal kilometres. It returned successful 2021, and will plaything by Earth again successful 2029, 2036, and 2068.

Until recently, location was a mini chance that Apophis could collide pinch Earth successful 2068. However, during Apophis’ attack successful 2021, astronomers utilized radar observations to refine their knowledge of nan asteroid’s orbit. These showed that Apophis would not deed our satellite for nan adjacent 100 years.

The Ramses ngo will rendezvous pinch Apophis successful February 2029, 2 months earlier its closest attack to Earth connected Friday April 13. It will past travel nan asteroid arsenic it approaches Earth. The extremity is to study really Apophis’s orbit, rotation and style will alteration arsenic it passes truthful adjacent to Earth’s gravitational field.

In 2016, Nasa launched nan “Origins, Spectral Interpretation, Resource Identification, and Security – Regolith Explorer” (Osiris-Rex) ngo to study nan near-Earth asteroid Bennu. It intercepted Bennu successful 2020 to cod samples of stone and ungraded from its surface. It dispatched nan rocks successful a capsule, which arrived connected Earth successful 2023.

The spacecraft is still retired there, truthful Nasa renamed it nan “Origins, Spectral Interpretation, Resource Identification and Security – Apophis Explorer” (Osiris-Apex) and assigned it to study Apophis. Osiris-Apex will scope nan asteroid conscionable aft its 2029 adjacent encounter. It will past alert debased complete Apophis’s aboveground and occurrence its engines, disturbing nan rocks and particulate that screen nan asteroid to uncover nan furniture underneath.

A adjacent flyby of an asteroid arsenic ample arsenic Apophis happens only erstwhile each 5,000 to 10,000 years. Apophis’s presence successful 2029 presents a uncommon opportunity to study specified an asteroid up close, and seeing really it is affected by Earth’s gravitational pull. The accusation gleaned will style nan measurement we take to protect Earth successful nan early from a existent slayer asteroid.

Ancient Egyptian mythology

When Ramses and Osiris-Apex meet up pinch Apophis successful 2029 they will inadvertently reenact a halfway constituent of ancient Egyptian cosmology. To nan ancient Egyptians, nan Sun was personified by respective powerful gods, main among them Re. The Sun’s mounting successful nan evening was interpreted arsenic Re dying and entering nan netherworld.

During his nighttime travel done nan netherworld, Re was menaced by nan awesome snake Apophis, who embodied nan powers of acheronian and dissolution. Only aft Apophis had been defeated could Re beryllium revitalised by Osiris, nan king of nan netherworld. Re could past erstwhile again beryllium reborn successful nan east, rising successful nan entity erstwhile more.

Detail from Egyptian tomb showing awesome feline of Re sidesplitting nan elephantine snake Apep (Apophis).
Hemro / Shutterstock

Tomb murals, coffins, and funerary papyri picture Apophis arsenic a large, coiled snake threatening Re arsenic he sails successful his Solar barque (sailing ship). But Apophis is ever defeated, his assemblage pierced by a spear aliases riven by knives.

Though nan asteroid Apophis poses nary threat successful nan adjacent future, Ramses (named aft nan pharaohs of nan aforesaid name, which meant “born of Re”) and Osiris-Apex will study it truthful that 1 time we will cognize really to conclusion it – aliases immoderate of its distant brethren.

Or Graur, Associate Professor of Astrophysics, University of Portsmouth

This article is republished from The Conversation nether a Creative Commons license. Read nan original article.