潛在威脅天體

被列為是有潛在危險的近地小行星，但它其實並不會對地球直接構成威脅。（在1996年拍攝的雷達影像）。]]

潛在危險天體（，縮寫：PHO）是指軌道有撞擊地球的可能，且其大小足以對地球造成全球或局部區域重大損害的近地天體 －無論是小行星或彗星。在2011年8月已經有1245顆潛在威脅小行星

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外部連結

• [http://neo.jpl.nasa.gov/risk/ Sentry Risk Table (current)] (NASA NEO Program)
• [http://andrew-lowe.ca/ALL-PHAS.HTM#Earth Very Close Approaches (<0.01 AU) of PHAs to Earth 1900-2200]
• [http://www.brera.mi.astro.it/sormano/teca.html TECA Table of Asteroids Next Closest Approaches to the Earth] , Sormano Astronomical Observatory
• [http://www.brera.mi.astro.it/sormano/mbpl.html MBPL - Minor Body Priority List (PHA Asteroids)] , Sormano Astronomical Observatory
• [http://swfound.org/media/16114/iac-10.e3.1b.4.pdf Responding to the Threat of Potentially-Hazardous Near Earth Objects] (PDF)
• [https://www.theguardian.com/science/2015/dec/23/risk-of-comet-hitting-earth-as-bad-as-asteroids-or-worse-say-researchers Risk of comet hitting Earth is greater than previously thought, say researchers] , The Guardian, 22 December 2015
• [https://www.minorplanetcenter.net/iau/lists/Sizes Conversion of Absolute Magnitude to Diameter] , Minor Planet Center