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2009 DD45

asteroid

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General referenceInterpretive dossier study · Crown Archives visual atlas
Record originEnglish Wikipedia
Text licenseCC BY-SA 4.0
Source revisionSep 6, 2026
Entity authorityQ211666 ↗
Source-derived summary

2009 DD45 is a very small Apollo asteroid that passed near Earth at an altitude of 63,500 km (39,500 mi) on 2 March 2009 at 13:44 UTC. It was discovered by Australian astronomers with the Siding Spring Survey at the Siding Spring Observatory on 27 February 2009, only three days before its closest approach to the Earth. Its estimated diameter is between 15 and 23 metres. This is about the same size as a hypothetical object that could have caused the Tunguska event in 1908.

BBC News Online cites the minimum distance as 72,000 km (45,000 mi) (about 1/5 lunar distances). 2009 DD45 passed farther away (40 thousand miles versus 4 thousand miles) but was substantially larger than 2004 FU162, a small asteroid about 6 m (20 ft) across which came within about 6,500 km (4,000 mi) in 2004, and is more similar in size to 2004 FH. With an observation arc of 7 days and an uncertainty parameter of 4, the asteroid will make its next close encounter with Earth on 29 February 2056 and then potentially around 3 March 2067.

See also

List of asteroid close approaches to Earth in 2009

References

External links

Universe Today article on 2009 DD45

100-meter asteroid will pass Earth Monday!

Editorial summary

This brief starts where responsible research should: with the source description of “2009 DD45” as asteroid. Everything that follows is an evidence route, not borrowed authority.

Editorial reviewA concise reference frame for defining the subject, testing terminology and identifying the institution closest to the evidence. The current lead gives the account dated anchors—2009, 1908, 2004, 2056—that can be checked directly. The selected authority fields contribute no independent date. The account is most persuasive where DD45 and asteroid can be independently traced.
Editorial analysis

Why this record matters

The subject matters to the general reference register because the source frames it as asteroid. Its deeper value depends on whether names, dates, institutions and citations support that framing.

Evidence profile

Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Sep 6, 2026. The linked authority identifier is Q211666. None of the 0 selected statements returned an explicit reference. The first chronological checks are 2009, 1908, 2004 and 2056.

Critical limits

Overview language is designed for orientation and should not be treated as a substitute for the evidence cited beneath it. The source lead contains qualifying language; that uncertainty should survive quotation, summary and reuse. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.

How to read it

Use the entry as an orientation point, then follow its citations and revision history. Names, dates and institutional relationships should be checked against the original record.

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The closest primary source, responsible institution and strongest cited specialist reference.

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  2. Expand the search: follow 2009 DD45 primary sources, 2009 DD45 archive and DD45 research across catalogues and specialist indexes.
  3. Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.

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Source & attribution

This entry incorporates text from “2009 DD45” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.