{"id":517475,"date":"2026-07-09T11:39:33","date_gmt":"2026-07-09T11:39:33","guid":{"rendered":"https:\/\/www.newsbeep.com\/nz\/517475\/"},"modified":"2026-07-09T11:39:33","modified_gmt":"2026-07-09T11:39:33","slug":"chinas-tianwen-2-spacecraft-reaches-earths-quasi-moon-after-one-billion-kilometer-journey","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/nz\/517475\/","title":{"rendered":"China\u2019s Tianwen-2 Spacecraft Reaches Earth\u2019s Quasi-Moon after One Billion-Kilometer Journey"},"content":{"rendered":"

On July 2, 2026, the Tianwen-2 probe closed to within 20 km (12.4 miles) of the small near-Earth asteroid 2016 HO3<\/a>, one of only seven Earth quasi-satellites identified to date, kicking off a science campaign ahead of an eventual sample-return attempt.<\/p>\n

\"Tianwen-2<\/a><\/p>\n

Tianwen-2 captured this image of 2016 HO3 on July 2, 2026 from a distance of about 20 km. Image credit: CNSA.<\/p>\n

2016 HO3 was discovered<\/a> on April 27, 2016 by the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS) at Haleakala Observatory in Hawai\u2019i.<\/p>\n

Also known as Kamo\u2019oalewa (meaning \u2018oscillating celestial fragment\u2019 in Hawaiian), the asteroid has an orbital period of one year and an estimated diameter of around 30 m (98 feet).<\/p>\n

\u201cAmong the known near-Earth asteroids, 2016 HO3 is an exceptionally rare Earth co-orbital object,\u201d said<\/a> Dr. Rongqiao Zhang from the Lunar Exploration and Space Engineering Center and colleagues.<\/p>\n

\u201cAs an Earth quasi-satellite, its orbital period is close to that of Earth, enabling low energy transfer, and it maintains a stable distance of about 0.1-0.3 astronomical units (AU) from Earth, providing favorable conditions for tracking, control, and communication.\u201d<\/p>\n

\u201cIts unusual orbit different, enigmatic origin, and largely uncharacterized physical properties make it a compelling candidate for addressing fundamental questions about the origins of Earth\u2019s quasi-satellites and the dynamical evolution of their orbits.\u201d<\/p>\n

\u201cOrbital dynamical models indicate that its current quasi-satellite state began around 100 years ago and is expected to persist for around 300 years,\u201d they added.<\/p>\n

\u201cIt is currently the closest Earth quasi-satellite (minimum distance 0.2 AU, with no exceedance beyond 0.3 AU throughout its dynamical stability), making it the most stable target of its kind<\/a>.\u201d<\/p>\n

\u201cThe plausible origins of this asteroid include local formation, gravitational capture, or ejection from the lunar surface as a result of a collision with another astronomical object.\u201d<\/p>\n

2016 HO3 is the primary target of the China National Space Administration (CNSA)\u2019s Tianwen-2 small bodies exploration mission<\/a>.<\/p>\n

\u201cThe Tianwen-2 spacecraft of China\u2019s Planetary Exploration Program was launched on May 29, 2025 from the Xichang Satellite Launch Center, utilizing the Long March 3B\/G2 rocket,\u201d the researchers said.<\/p>\n

\u201cChina\u2019s planetary exploration program, known as the Tianwen Project, sets forth an ambitious vision for deep space exploration through a series of four flagship missions.\u201d<\/p>\n

\u201cTianwen-1 marked China\u2019s inaugural journey to Mars, while Tianwen-2 targets small bodies, Tianwen-3 is designed for Mars sample return, and Tianwen-4 aims to investigate the Jupiter system.\u201d<\/p>\n

\u201cAmong these, Tianwen-2 stands out for its dual objectives: the mission will not only conduct in-orbit observations and collect samples from the near-Earth asteroid 2016 HO3, but will also undertake a subsequent close investigation of the main-belt comet 311P.\u201d<\/p>\n

After a 400-day journey covering roughly one billion km (0.6 billion miles), Tianwen-2 arrived within about 20 km of 2016 HO3 on July 2, 2026.<\/p>\n

\u201cAlong the way, Tianwen-2 carried out a series of deep-space maneuvers and mid-course corrections,\u201d the mission scientists said in a statement.<\/p>\n

\u201cThe probe spotted the asteroid on June 6, then executed capture control at a distance of 30,000 km on June 7, achieving co-orbital flight with the object. By June 19, it had closed to within 2,000 km.\u201d<\/p>\n

\u201cWe used the resulting optical navigation data to refine the asteroid\u2019s ephemeris, sharpening its known position from an accuracy of hundreds of km \u2014 based solely on ground-based observations \u2014 down to just a few km.\u201d<\/p>\n

\u201cTianwen-2 will now begin a more detailed phase of scientific investigation, characterizing the asteroid\u2019s shape, surface composition, and internal structure to lay the groundwork for sample collection.\u201d<\/p>\n","protected":false},"excerpt":{"rendered":"On July 2, 2026, the Tianwen-2 probe closed to within 20 km (12.4 miles) of the small near-Earth…\n","protected":false},"author":2,"featured_media":517476,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[23],"tags":[7878,7871,607,17229,3146,22865,49431,109089,111,139,69,249603,147,3145,392,7877],"class_list":["post-517475","post","type-post","status-publish","format-standard","has-post-thumbnail","category-space","tag-2016-ho3","tag-asteroid","tag-china","tag-cnsa","tag-earth","tag-kamooalewa","tag-near-earth-object","tag-near-earth-asteroid","tag-new-zealand","tag-newzealand","tag-nz","tag-quasi-satellite","tag-science","tag-solar-system","tag-space","tag-tianwen-2"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts\/517475","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/comments?post=517475"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts\/517475\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/media\/517476"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/media?parent=517475"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/categories?post=517475"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/tags?post=517475"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}