OSIRIS-APEX

Origins, Spectral Interpretation, Resource Identification and Security – Apophis Explorer

active Mission

The image is zoomed in on Earth's globe, which takes up the entirety of the frame. In front of it hovers a metal box with wings.

OSIRIS-APEX, a follow-on to OSIRIS-REx, will study the physical changes to asteroid Apophis after the asteroid’s rare close encounter with Earth in 2029.

Mission Type

Asteroid Rendezvous

destination

Apophis

arrival

April 2029

objective

Study how a close pass of Earth affects a “stony” asteroid

Dec. 1, 2023

NASA’s OSIRIS-APEX to Fly Closer to Sun to Reach Asteroid Apophis

Reinvented as NASA’s OSIRIS-APEX, the spacecraft formerly known as OSIRIS-REx is about to face the first major test of its mission to asteroid Apophis: On Jan. 2, 2024, flew closer to the Sun than ever before, exposing its components to higher temperatures than they were designed to endure.

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Overview

OSIRIS-APEX is a mission to study the physical changes to asteroid Apophis that will result from its rare close encounter with Earth in April 2029. That year, Apophis’ orbit will bring it within 20,000 miles (32,000 kilometers) of Earth’s surface — closer to Earth than our highest-altitude satellites. Our planet’s gravitational pull is expected to alter the asteroid’s orbit, change how and how fast it spins on its axis, and possibly cause quakes or landslides that will alter its surface. OSIRIS-APEX will allow scientists on Earth to observe these changes. Additionally, the OSIRIS-APEX spacecraft will dip toward the surface of Apophis – a “stony” asteroid made of silicate (or rocky) material and a mixture of metallic nickel and iron – and fire its engines to kick up loose rocks and dust. This maneuver will give scientists a peek at the composition of material just below the asteroid’s surface.

OSIRIS-APEX, formerly OSIRIS-REx, will use its thrusters to stir up rocks and dust on the surface of Apophis to allow scientists to see just below. Credit: NASA's Goddard Space Flight Center Conceptual Image Lab

NASA Encyclopedia

Apophis

When it was discovered in 2004, Apophis was identified as one of the most hazardous asteroids that could impact Earth. But the asteroid was removed from the impact risk list after astronomers tracked Apophis and its orbit became better determined.

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A white, grey, and black pixelated image, with three bright blobs spaced out across the center, and circled in white.

These images of asteroid Apophis were recorded by radio antennas at N Deep Space Network’s Goldstone complex in California and the Green Bank Telescope in West Virginia. The asteroid was 10.6 million miles (17 million kilometers) away, and each pixel has a resolution of 127 feet (38.75 meters).

NASA/JPL-Caltech and NSF/AUI/GBO

mission lead

Dani Mendoza DellaGiustina

Dani Mendoza DellaGiustina, the principal investigator of OSIRIS-APEX, is a planetary scientist with expertise in surface and near-surface structure of small airless worlds across the solar system. She was previously the deputy principal investigator for OSIRIS-REx.

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