Enlarge / An artist’s conception of the Lucy spacecraft flying by a Trojan asteroid. (credit: NASA)

A little more than two years have passed since the Lucy mission launched on an Atlas V rocket, ultimately bound for asteroids that share an orbit with Jupiter. After a gravity assist from Earth in 2022, the spacecraft has been making a beeline for an intermediate target, and now it is nearly there.

On Wednesday, the $1 billion mission is due to make its first asteroid flyby, coming to within 265 miles (425 km) of the small main belt asteroid Dinkinesh. In a blog post , NASA says the encounter will take place at 12:54 pm ET (16:54 UTC).

About an hour before the encounter, the spacecraft will begin attempting to lock on to the small asteroid so that its instruments are oriented toward it. This will allow for the best possible position to take data from Dinkinesh as Lucy speeds by at 10,000 mph (4,470 meters per second).

Enlarge / NASA's Psyche spacecraft is cocooned inside the payload shroud on top of SpaceX's Falcon Heavy rocket. (credit: Trevor Mahlmann/Ars Technica)

A roughly 3-ton spacecraft is ready for launch Friday from NASA's Kennedy Space Center in Florida to begin a six-year trip to an enigma in the asteroid belt, an unusual metallic world the size of Massachusetts that could hold clues about the formation of Earth and other rocky planets.

This mission, named Psyche, will survey its namesake asteroid for at least 26 months, moving to different altitudes to map the metal world with three science instruments. Like all missions exploring the Solar System, the Psyche spacecraft has a long journey to reach its destination, covering some 2.2 billion miles (3.6 billion kilometers) with the help of plasma engines.

No one knows what the spacecraft will find when it reaches the asteroid Psyche. The best images of the asteroid captured through telescopes only show Psyche as a fuzzy blob a few pixels wide. Scientists know it is dense and at least partially made of metal, primarily iron and nickel. The leading hypothesis among Psyche's science team is that the asteroid is likely a leftover remnant from the early history of the Solar System 4.5 billion years ago, the exposed core of a failed planet that may have had its outer layers of rock blasted away during collisions with other objects in that chaotic time.

Enlarge / A view of the outside of the OSIRIS-REx sample collector. Scientists have found evidence of both carbon and water in initial analysis of this material. The bulk of the sample is located inside. (credit: NASA/Erika Blumenfeld & Joseph Aebersold)

JOHNSON SPACE CENTER, Texas—As they unveiled the first samples recovered from an asteroid on Wednesday, scientists were giddy at the prospects of what this material will tell us about the origin of our planet and possibly even ourselves.

After seven years in space, a small spacecraft carrying samples from the asteroid Bennu landed in a Utah desert in late September. Following carefully choreographed procedures to prevent the contamination of the asteroid dust and rocks from life on Earth, the samples were transferred to a clean room at Johnson Space Center in Houston two weeks ago. Since then, scientists have examined some of the material that was collected outside of the primary container to glean some initial insights. They revealed some of their first data during an event at the center on Wednesday.

"Boy, did we really nail it," said Dante Lauretta, a scientist from the University of Arizona who is the principal investigator of the OSIRIS-REx mission.

Enlarge / The lid is open on the OSIRIS-REx sample return canister, revealing a tantalizing ring of dust outside the main sample collection chamber. (credit: Dante Lauretta )

Dante Lauretta has waited nearly 20 years to get his hands on pristine specimens from an asteroid, which he says is a key to unlocking answers to mysteries about the origin of life on Earth. On Tuesday, he got his first look at dust grains returned by NASA's OSIRIS-REx mission.

Because they want to be sure, members of the OSIRIS-REx science team will wipe some of the dust from the asteroid sample canister and send it to a laboratory for analysis. But there's little question the dust grains visible immediately after scientists opened the lid to the canister are from asteroid Bennu, where the OSIRIS-REx spacecraft captured rocks during a touch-and-go landing in 2020.

The spacecraft completed its round-trip journey to asteroid Bennu with a near-bullseye landing of its sample return capsule Sunday morning in Utah. The OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer) mothership released the capsule to plunge into the atmosphere while it fired its thrusters to maneuver on a trajectory to head back into the Solar System for an extended mission to visit another asteroid.

Enlarge / Dante Lauretta (right), OSIRIS-REx principal investigator, approaches the sample return capsule Sunday at the Utah Test and Training Range. (credit: NASA/Keegan Barber )

A small capsule carrying pristine specimens from an asteroid parachuted to landing in the Utah desert Sunday, capping a seven-year voyage through the Solar System to bring home samples for eager scientists seeking clues about the origins of life.

NASA's OSIRIS-REx mission brought back the largest unspoiled sample of material ever returned to Earth from beyond the Moon, probably on the order of about 250 grams, or roughly 8 ounces, according to estimates. The spacecraft collected the samples from asteroid Bennu, a loosely-bound rocky world about the size of a small mountain, during a touch-and-go landing in October 2020.

It's the third asteroid sampling mission in history, and the first for the United States, following two Japanese spacecraft that returned a smaller quantity of asteroid specimens to Earth in 2010 and 2020.

Enlarge / Scientists created this mosaic of asteroid Bennu using imagery collected by NASA's OSIRIS-REx spacecraft. The asteroid spans about 1,600 feet (500 meters) across.

A NASA spacecraft will complete a round-trip journey to an asteroid this weekend, returning to Earth after a seven-year voyage to bring back unspoiled rock specimens from an alien world that could yield insights into the formation of life.

The landing Sunday at 8:55 am local time in Utah (10:55 am EDT or 14:55 UTC) will wrap up a round-trip journey of 4.4 billion miles (7.1 billion kilometers) for NASA's robotic OSIRIS-REx mission. The return will set into motion another sequence of tightly-choreographed events to secure the asteroid sample capsule, fly it halfway across the country to a NASA facility at the Johnson Space Center in Houston, then open it up to reveal the bounty inside.

"The spacecraft trajectory and performance have just been spot on," said Sandra Freund, OSIRIS-REx's program manager at Lockheed Martin, which built and operates the spacecraft on behalf of NASA. "We have just a few remaining steps before we have Bennu samples on the ground."

Enlarge / A look inside the clean room where OSIRIS-REx's samples will be stored. (credit: NASA)

Christmas Day for scientists who study asteroids is coming in just two months when a small spacecraft carrying material from a distant rubble pile will land in a Utah desert.

The return of the OSIRIS-REx sample container on September 24 will cap the primary mission to capture material from an asteroid—in this case, the carbonaceous near-Earth asteroid Bennu—and return some of its pebbles and dust to Earth.

It has been a long time coming. This mission launched seven years ago and has been in the planning and development phase for over a decade. To say the scientists who have fought for and executed this mission are anxious and excited is an understatement. But there is an additional frisson with OSIRIS-REx, as scientists are not entirely sure what they've been able to pull away from the asteroid.

Enlarge / A recent Hubble photo shows the 10,000 km tail of debris left behind by DART's impact. (credit: NASA/ESA/STScI/Hubble )

On Tuesday, NASA announced that its first test of a potential planetary defense system was a notable success. The Double Asteroid Redirect Test (DART) successfully smashed a spacecraft into an asteroid in late September, hoping to alter its orbit around a larger companion. Any changes in the orbit, however, would be difficult to pick up and potentially require months of follow-up observations. But the magnitude of the orbital shift was large enough that ground-based observatories picked it up already.

Meanwhile, a lot of hardware is also picking up the debris that shot out from the impact, giving scientists a lot of information about the collision and the asteroid.

New orbit, who dis?

Dimorphos is less than 200 meters across and cannot be resolved from Earth. Instead, the binary asteroid looks like a single object from here, with most of the light reflecting off the far larger Didymos. What we can see, however, is that the Didymos system sporadically darkens. Most of the time, the two asteroids are arranged so that Earth receives light reflected off both. But Dimorphos' orbit sporadically takes it behind Didymos from Earth's perspective, meaning that we only receive light reflected off one of the two bodies—this causes the darkening.

Enlarge / The DART spacecraft is prepared for launch. (credit: NASA/Johns Hopkins APL/Ed Whitman )

Monday will see NASA's first attempt at real-world testing of a technology that it hopes can protect the Earth from the dangers posed by impacts from large asteroids. The Double Asteroid Redirect Test, or DART, will smash a spacecraft into a small asteroid called Dimorphos at 7:14 pm US Eastern time in the expectation that the impact will alter Dimorphos' orbit around the nearby large asteroid Didymos. If successful, then we can have some confidence that we can alter the orbit of small objects that pose a threat of colliding with Earth, sending them off into orbits where they no longer create a risk of catastrophic impact.

There are still things that can go wrong. As we detailed earlier , the camera on DART won't even be able to resolve its target until under two hours prior to the collision, and the final trajectory to impact will be handled by its on-board software, rather than controllers on Earth.

NASA will be hosting pre- and post-impact briefings for the press, which Ars will be attending, so expect updates later today. One option if you want to watch for yourself is coverage on NASA TV, which will start at 6 pm US Eastern.