On 13 April 2029, the roughly Eiffel Tower-sized asteroid Apophis will safely pass just 32,000 kilometres above Earth—inside the orbit of many geosynchronous satellites—and briefly become visible to the naked eye under clear, dark skies for around two billion people across Europe, Africa and parts of Asia, during a close encounter expected only about once per millennium.

On Friday, 13 April 2029, an asteroid about as tall as the Eiffel Tower will pass roughly 32,000 kilometres above Earth’s surface. It will come closer to the ground than satellites parked in geostationary orbit, brighten enough to see without a telescope and move rapidly across the stars.

The asteroid is 99942 Apophis. Despite the unsettling scale of the encounter, it will miss safely. NASA says there is no danger to Earth, astronauts or satellites, and modern tracking has ruled out an Apophis impact for at least the next century.

What makes the night unusual is not a threat but access. The European Space Agency estimates that about two billion people across much of Europe and Africa and parts of Asia could briefly see Apophis with the naked eye, provided their sky is clear and dark.

Thirty-two thousand kilometres is the altitude, not the centre-to-centre distance

The quoted 32,000 kilometres is the gap between Apophis and Earth’s surface near closest approach. The distance from the asteroid to Earth’s centre will be larger by one Earth radius. Mixing those two measurements is one reason published flyby figures can appear to disagree.

NASA describes Apophis as having a mean diameter of about 340 metres and a long axis of at least 450 metres. ESA commonly uses roughly 375 metres across. The asteroid has not changed size between those estimates. Radar suggests an elongated, possibly two-lobed body, so a mean diameter, a broad size estimate and a longest dimension are not interchangeable.

The Eiffel Tower is about 330 metres tall to its tip, making it a useful scale comparison rather than a claim that the asteroid has the same shape or exact dimensions.

Geostationary satellites operate about 35,786 kilometres above the equator. Apophis will pass below that altitude, but altitude alone does not describe a collision route. The asteroid approaches on an inclined trajectory and crosses the equatorial plane outside the densely occupied geostationary region. Many other spacecraft orbit hundreds or thousands of kilometres above Earth and will remain well below it.

It will look like a moving star, not a meteor

Apophis will never enter the atmosphere. There will be no fireball, glowing tail or explosive flash. To an unaided observer it should look like a moderately bright point of light whose motion against the background stars becomes noticeable.

A NASA Jet Propulsion Laboratory observing preview says it may cross more than the apparent width of the full Moon in a minute near its fastest. Peak estimates put it around third magnitude, comparable to an ordinary star visible from a reasonably dark location.

The broad naked-eye corridor favours Europe, Africa and western parts of Asia around the closest encounter. Seeing it from a particular town will still depend on the exact hour, the direction and altitude of the asteroid, local cloud, haze, buildings and skyglow.

“Two billion people” therefore describes a potential audience, not a forecast that two billion will simultaneously watch. Many will be indoors, asleep, under cloud or surrounded by enough artificial light to lose a modest star. Binoculars should make the target easier, but only if an observer first knows where to aim.

SpaceDaily has also covered a broader 2026 visibility calculation that put as many as 7.6 billion people somewhere inside the cumulative viewing region over roughly seven hours. That larger number uses a changing global footprint and more permissive geometry. ESA’s roughly two-billion figure is a simpler description of the best-known naked-eye corridor around the main event.

How rare is “once per millennium”?

The answer depends on which asteroids and distances count as comparable. A JPL radar planning page describes a flyby this close by an asteroid more than 300 metres wide as occurring roughly once every 1,000 years.

Current summaries use longer intervals. NASA says an asteroid this large passes this close only every few thousand years on average. ESA has cited once every 5,000 to 10,000 years. A 2025 NASA inspector-general report used roughly 7,500 years.

Those statements are not predictions that the next Apophis-like passage will arrive on a schedule. They are statistical recurrence estimates built from the inferred population and orbits of near-Earth objects. Change the minimum diameter, the maximum flyby distance or the estimated size of Apophis, and the frequency changes too.

The cautious conclusion is stable: a known asteroid hundreds of metres wide passing inside geostationary altitude is extraordinarily rare on a human timescale. “About once per millennium” is a defensible older shorthand, while newer estimates suggest the event may be rarer still.

The asteroid was once a threat on paper

Apophis was discovered in June 2004. With only a short arc of observations available, early orbit calculations briefly left open a small possibility of a 2029 impact. The uncertainty region narrowed as astronomers recovered older images and collected more precise measurements.

Radar observations from Goldstone and Green Bank in March 2021 provided the decisive improvement. They allowed NASA to exclude an impact in 2068 as well as earlier concern dates and to remove Apophis from its Sentry impact-risk table.

SpaceDaily’s earlier account of the flyby and OSIRIS-APEX explains why eliminating the impact risk did not end scientific interest. Earth’s gravity will substantially redirect the asteroid’s solar orbit while tidal forces pull unevenly across its body.

Those forces may alter Apophis’s spin, trigger small landslides or expose fresher material. Measuring the changes could reveal how tightly the asteroid is assembled and whether its interior behaves as a coherent rock or a looser rubble pile.

Earth becomes the laboratory

NASA’s OSIRIS-APEX spacecraft is scheduled to meet Apophis after the encounter. It is the former OSIRIS-REx probe that returned samples from Bennu in 2023, redirected for an extended mission. ESA, working with Japan, is developing Ramses to arrive before the flyby and watch the asteroid change in real time.

Ground observatories will measure its position, brightness, rotation and radar shape. Coordinating those data with spacecraft observations could show what a close planetary encounter does to an asteroid before, during and after maximum tidal stress.

For the public, the same experiment will pass overhead as a point of light. There is no need for alarm and, under the right sky, no need for a telescope. The challenge will simply be to know the predicted track, find a dark view and look up at the correct minute.

Apophis will be gone quickly. The measurements it leaves behind may shape planetary-defence models for decades.