Asteroid 2017 FN1 flew past Earth at 0.15 LD


A newly discovered, car-sized asteroid 2017 FN1 flew past Earth at a distance of 0.15 LD (~57 600 km/ 35 790 miles) from the surface at 21:01 UTC on March 20, 2017. This is the 13th known asteroid to flyby Earth within 1 lunar distance since the start of the year (according to data available September 20, 2017).

2017 FN1 belongs to the Apollo group of asteroids and has an estimated diameter between 2 and 4.5 meters (6.5 – 14.7  feet). It flew past Earth at a speed relative to the Earth of 18.26 km/s.

This object was first observed at Mount Lemmon Survey (MLS) on March 20, 2017. MLS is a part of the Catalina Sky Survey. It uses a 1.52 m (60 inches) Cassegrain reflector telescope operated by the Steward Observatory at Mount Lemmon Observatory, which is located at 2 791 meters (9 157 feet) in the Santa Catalina Mountains northeast of Tucson, Arizona. It is currently one of the most prolific surveys worldwide, especially for discovering near-Earth objects.

Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Close-Approach Data ]

As of March 18, 2017, there are 15 798 known near-Earth asteroids (NEAs). Of them, 8 602 belong to the Apollo group of asteroids – Earth-crossing NEAs with semi-major axes larger than Earth's (named after asteroid 1862 Apollo).


Asteroid 2017 FN1 at Minor Planet Center, CNEOS

Featured image: The green line indicates the object's apparent motion relative to the Earth, and the bright green marks are the object's location at approximately one hour intervals. The Moon's orbit is gray. The blue arrow points in the direction of Earth's motion and the yellow arrow points toward the Sun. Edit: TW

If you value what we do here, create your ad-free account and support our journalism.


Commenting rules and guidelines

We value the thoughts and opinions of our readers and welcome healthy discussions on our website. In order to maintain a respectful and positive community, we ask that all commenters follow these rules:

  • Treat others with kindness and respect.
  • Stay on topic and contribute to the conversation in a meaningful way.
  • Do not use abusive or hateful language.
  • Do not spam or promote unrelated products or services.
  • Do not post any personal information or content that is illegal, obscene, or otherwise inappropriate.

We reserve the right to remove any comments that violate these rules. By commenting on our website, you agree to abide by these guidelines. Thank you for helping to create a positive and welcoming environment for all.


  1. Any historical data of near misses? It appears asteroid orbits are calculated and can be tracked. Is there projection data of anticipated near misses? Does close proximity to earth affect the projected orbit asteroids? This activity is interesting to say the least.

    1. Yes. Yes. What do you mean? Yes. Yes, it sure is interesting. 🙂

      CNEOS holds a great and easy to use database. You can browse our archive, too:

      This was from March 4 (

      As of March 4, 2017, we know for a total of 381 near-Earth objects that already flew past Earth within 1 lunar distance since 1910 or will over the next 172 years. This number is constantly growing as new objects get discovered.

      In 2016, there were 52 such objects and the closest was 2016 DY30 on February 25. Its size is between 2.1 and 4.7 m (6.8 – 15.4 feet) and if flew past us at 0.04 LD (15 360 km / 9 544 miles). In 2015, there were 26 such objects.

      1. Is there projection data of anticipated near misses?
        As of March 4, 2017, we know for a total of 381 near-Earth objects that already flew past Earth within 1 lunar distance since 1910 or will over the next 172 years.
        Thanks for answering the above. Where do the new objects come from and how do we know of the anticipated future NEOs over the next 172 years? Of the known NEOs how many get pushed off their charted orbits due to close encounters with earth or any of the other planets they may interact with? On the surface it seems there are a lot of potential impacts but they rarely happen. With an increase in activity that potential surely increases.

  2. It would be interesting to have an impression of the impact effect if each of these had struck the Earth (shock wave, crater, kinetic energy). Is there such a metric comparable to how we guage earthquakes?

Leave a reply

Your email address will not be published. Required fields are marked *