Asteroid Tracker: Dated NASA Close Approaches

Start with the date, then read the object record

The table above is a retained sample for one UTC-calendar feed window. It is not a rolling list of every object in the sky. Read the feed date and retrieval time before comparing two visits. A snapshot collected late on one day can still be useful the next morning, but it belongs to the earlier window and is labelled stale. An unavailable table means there is no usable retained sample; it is not evidence that the sky is empty.

Open the asteroid summary list using the button, select an object and compare its source date, nominal miss distance and available size estimate. The JPL link identifies the individual object, rather than a place on the globe. PocketWorld takes up to fifteen matching Earth approaches from the requested day, ordered by nominal distance with unknown distances last. A row's place in that sample is not an assessment of danger. An object omitted from the sample may simply be outside its date window or sample limit.

Distance, diameter and PHA answer different questions

Miss distance describes the predicted separation during an encounter. It is not distance above your house or a ground-track coordinate. A smaller nominal value does not by itself give a collision probability. New observations can revise an orbit and the encounter calculation. The CNEOS close-approach data notes explain why uncertainties and updated solutions matter. For comparisons, use the same object, encounter date and units, rather than comparing unrelated rows merely because their names look similar.

The diameter fields are estimates, presented as a range when both bounds are supplied. A single displayed diameter in the interactive card is the midpoint of that range, not a measured shape or a claim of precision. Unknown values stay unknown instead of becoming zero. The range cannot establish composition, atmospheric behaviour or damage to a particular country. Those require information and modelling that this page does not provide.

PHA means potentially hazardous asteroid. CNEOS defines the class using orbital proximity and absolute magnitude: an Earth minimum orbit intersection distance of 0.05 astronomical units or less and absolute magnitude H of 22 or brighter. These are classification criteria, not a prediction that a collision will occur during the listed encounter. Read the CNEOS definitions when interpreting that flag. A missing classification is shown as unknown; it is never converted into a reassuring negative.

US and Canadian readers use the same encounter data

An asteroid approaching Earth does not belong to a US state or Canadian province. A geographic filter cannot turn this global source into a forecast for New York, Texas, Ontario or British Columbia. Your location matters to a genuine observing plan, which needs suitable ephemerides, the observer's coordinates, local horizon and time. The list here supplies none of that observing geometry. Switching country or zooming the map therefore does not change a close approach into a local event.

For US readers following a reported risk, the appropriate next step is the dated object information and NASA JPL Sentry's monitoring explanation. Sentry concerns possible impacts assessed from orbital solutions; the daily close-approach list serves a different purpose. This page neither calculates a risk corridor nor issues emergency advice. Recheck the official record when an article or social post quotes a date without its source or confuses a PHA flag with an imminent impact.

Canadian readers can also explore the Canadian Space Agency's NEOSSat mission and its open image collection. NEOSSat contributes observations of asteroids and other objects. Downloadable observation images are not a province-specific danger map, and they are not the live input used by this PocketWorld table. Keeping the mission's observation products separate from the daily NASA approach sample makes a comparison more useful and prevents a Canadian label from implying local exposure.

Choose the right PocketWorld tool

Use this page for a source-reading workflow: verify the retained window, identify the object, read the encounter fields and follow the official record. For objects orbiting Earth, use the satellite catalogue instead; for discarded spacecraft and related catalogue categories, see the space debris guide. Those are different data sets with different gaps. Neither a satellite marker nor an asteroid's encounter date should be used to fill a missing position in the other tool.

Related tools in other languages

• Карта астероидов