ESA’s Planetary Defence team has released a close-approach fact sheet for asteroid 1997 NC1, a large near-Earth object making a safe pass by our planet on June 27, 2026. The flyby brings a sizable space rock close enough for careful tracking, yet far enough away to leave Earth completely out of harm’s path.
The object, formally known as (152637) 1997 NC1, is drawing attention because of its size and its proximity. At closest approach, it passes about 1.6 million miles, or 2.6 million kilometers, from Earth. That is roughly 6.7 times the average distance between Earth and the Moon.
For planetary-defense teams, this kind of event is useful. Large asteroids that pass near Earth give scientists a chance to refine orbits, test observing networks and show how international tracking systems keep watch over near-Earth space. For skywatchers with the right equipment, the asteroid may also appear as a faint moving point of light.
The flyby peaks on June 27
Today’s closest approach occurs on Saturday, June 27, 2026. ESA’s close-approach information places the event in the late morning in Coordinated Universal Time, with the asteroid moving through space at high speed as it passes Earth at a safe distance.
The asteroid’s path has been tracked for years. Its orbit is well enough known for agencies such as ESA and NASA to predict this flyby and its future returns. That predictability is central to planetary defense. The aim is to know where these objects are going long before they become a public concern.
Although 1.6 million miles sounds large by everyday standards, it counts as a close approach in astronomical terms. Space is vast and near-Earth objects are often discussed using lunar distances. By that measure, 1997 NC1 passes at a distance of a little under seven Moon distances.
The timing also makes this event unusually visible to the global asteroid-tracking community. Observatories can follow the object before, during and after its closest approach. Each measurement helps refine the asteroid’s path around the Sun.
How large 1997 NC1 may be
ESA estimates that 1997 NC1 is between about 2,461 feet and 5,413 feet wide. In metric units, that is roughly 0.75 kilometer to 1.65 kilometers across. The range is broad because asteroid sizes are often inferred from brightness.
A bright asteroid can be large and dark, or smaller and more reflective. Without close-up spacecraft images, scientists estimate size by combining observed brightness with assumptions about how much sunlight the surface reflects. That reflectivity is called albedo.
The upper end of the estimate makes 1997 NC1 a substantial near-Earth asteroid. A common comparison is the Empire State Building, which puts its possible diameter at roughly the scale of two to four such towers. That comparison gives a rough sense of size, although asteroids are irregular bodies rather than neat vertical structures.
Objects in this size range matter to planetary-defense scientists because they are large enough to deserve long-term attention. Tracking them does more than serve public curiosity. It builds a record of motion that improves future predictions.
The asteroid was discovered nearly three decades ago by an asteroid-tracking system in Hawaii. Since then, observations have allowed scientists to calculate its orbit and identify when it will come close to Earth.
Why space agencies are tracking it
The label potentially hazardous asteroid can sound alarming, but in planetary science it has a specific technical meaning. It flags an asteroid that is large enough and whose orbit can bring it relatively close to Earth. The label helps agencies prioritize observation.
For 1997 NC1, the June 27 flyby is safe. The value of tracking comes from preparation and precision. By measuring an asteroid’s position over time, scientists reduce uncertainty in its predicted orbit.
Planetary defense depends on early detection. NASA, ESA and other space agencies maintain surveys, databases and follow-up observations to monitor near-Earth asteroids and other objects. The goal is to know which objects are nearby, where they are headed and how their paths may change over time.
Asteroid orbits can be influenced by gravity from planets during close approaches. Small effects can also matter over long stretches of time. Continued observations help scientists account for those changes and update future predictions.
Events like this also test communication. A large asteroid passing near Earth can attract dramatic headlines. Official close-approach fact sheets give the public a clearer picture, including the distance, timing, size estimate and safety assessment.
How skywatchers may see it
For observers, binoculars and small telescopes may be enough to spot 1997 NC1 under favorable conditions. The asteroid will appear as a small point of light rather than a detailed disk. Its motion against the background stars is the clue that it is nearby in solar system terms.
Visibility depends on location, weather, sky darkness, timing and equipment. Moonlight can make faint targets harder to see. Light pollution from cities can also reduce the odds of spotting the asteroid.
Astronomers often track near-Earth asteroids by taking repeated images of the same patch of sky. Stars stay fixed from image to image, while the asteroid shifts position. That apparent motion reveals the object’s path across the sky.
For casual observers, the best approach is usually to consult local astronomy groups or live observing projects. They can provide sky charts and timing for specific regions. A large asteroid at millions of kilometers away still requires patience and a good viewing setup.
The flyby also highlights how much of asteroid science happens from the ground. Telescopes on Earth can discover, track and measure these objects long before any spacecraft gets close to them.
Its next close visit comes in 2133
After today’s pass, NASA calculations indicate that 1997 NC1 will make its next similarly close approach to Earth in 2133. That long gap shows how orbital geometry shapes asteroid encounters. Earth and the asteroid must arrive at the right parts of their solar orbits at nearly the same time.
The 2026 flyby is part of a larger pattern of safe close approaches. In 2022, an asteroid of similar size, called 1994 PC1, passed Earth from an even closer distance. These events are reminders that near-Earth space is active and constantly monitored.
Large safe flybys also help scientists improve catalogs of near-Earth objects. Each precise measurement strengthens the long-term record. Over decades, that record becomes one of the most important tools for assessing future risk.
Today’s encounter is therefore both a skywatching opportunity and a planetary-defense exercise. A giant asteroid is sweeping past Earth, scientists know where it is and the data gathered during the event will help sharpen the picture for years to come.
