{"id":100956,"date":"2025-07-29T02:42:10","date_gmt":"2025-07-29T02:42:10","guid":{"rendered":"https:\/\/www.europesays.com\/us\/100956\/"},"modified":"2025-07-29T02:42:10","modified_gmt":"2025-07-29T02:42:10","slug":"intercepting-3i-atlas-at-its-closest-approach-to-jupiter-with-the-rejuvenated-juno-spacecraft-by-avi-loeb-jul-2025","status":"publish","type":"post","link":"https:\/\/www.europesays.com\/us\/100956\/","title":{"rendered":"Intercepting 3I\/ATLAS at Its Closest Approach to Jupiter with the Rejuvenated Juno Spacecraft | by Avi Loeb | Jul, 2025"},"content":{"rendered":"

\"Avi<\/a>Zoom image will be displayed\"\"The Juno spacecraft. (Image credit: NASA<\/a>)<\/p>\n

The interstellar object 3I\/ATLAS<\/a> was discovered on July 1, 2025. It is expected to arrive at a distance of 53.6 million kilometers from Jupiter<\/a> on March 16, 2026.<\/p>\n

In a new paper that I wrote (accessible here<\/a>) with the brilliant Adam Hibberd and Adam Crowl, we show that applying a thrust of 2.675 kilometers per second on September 14, 2025 can bring the Juno spacecraft<\/a> from its orbit around Jupiter to intercept the path of 3I\/ATLAS.<\/p>\n

The Juno spacecraft, named after the wife and sister of Jupiter<\/a> in Roman mythology, was launched from Cape Canaveral on August 5, 2011, and entered a polar orbit<\/a> around Jupiter on July 5, 2016 to conduct scientific measurements of Jupiter\u2019s composition, gravitational field, magnetic field, and polar magnetosphere. Juno was originally planned to be intentionally deorbited into Jupiter\u2019s atmosphere, but has since been approved to continue orbiting.<\/p>\n

The close encounter of 3I\/ATLAS to Jupiter provides a rare opportunity to shift Juno from its current orbit around Jupiter to intercept the path of 3I\/ATLAS at its closest approach to Jupiter. The instruments available on Juno, namely a near- infrared spectrometer, magnetometer, microwave radiometer, gravity science instrument, energetic particle detector, radio and plasma wave sensor, UV spectrograph and visible light camera\/telescope, can all be used to probe the nature of 3I\/ATLAS from a close distance.<\/p>\n

Our analysis exploits the software package known as Optimum Interplanetary Trajectory Software (OITS)<\/a>, developed by Adam Hibberd. OITS solves the Lambert problem for one orbital cycle only: given two times, what are the 2 orbital arcs that connect them? Assuming that the positions at the beginning of the arc and the end of the arc are known, then there are 2 solutions, a short way and a long way. Having the short way and long way solutions, the way with the maximum velocity thrust \u2206V is rejected, leaving the lowest \u2206V solution. This procedure is conducted iteratively with different trial values of the initial and final times, until OITS has converged on the overall minimum \u2206V solution.<\/p>\n

Our calculation focuses on an intercept, namely a flyby, since a rendezvous, where the target\u2019s velocity is matched by the spacecraft, is out-of-the- question, owing to the excessively high hyperbolic speed of 3I\/ATLAS relative to Jupiter, 65.9 kilometers per second.<\/p>\n

Based on this approach, we used OITS for a Juno \u2206V application window covering the present as at the time of writing (July 27, 2025) to the possible end of the mission which is currently scheduled to occur in September 2025.<\/p>\n

The feasibility of intercepting 3I\/ATLAS depends on the current amount of fuel available from the propulsion system of Juno. However, some inferences can be drawn from the total \u2206V available at the beginning of the Juno mission. On its interplanetary trajectory, Juno conducted 2 Deep Space Maneuvers, and 1 Jupiter orbital insertion, both of which would have placed a significant demand on the chemical propulsion employed by Juno (Hydrazine and oxidizer nitrogen tetroxide).<\/p>\n

The fuel reservoir on Juno allows an overall initial \u2206V available of 2.74 kilometers per second, similar to the \u2206V of 2.675 kilometers per second required to intercept 3I\/ATLAS. However, the similarity of these numbers motivated our paper. This value is similar to the required \u2206V for Juno to intercept 3I\/ATLAS. Although the engine of Juno was not operated since 2017, the required \u2206V might potentially be within Juno\u2019s performance envelope. In that case, Juno would be able to get close to 3I\/ATLAS and use its instruments to probe the nature of the interstellar object and any cloud of gas or dust around it.<\/p>\n

Our paper shows that applying a thrust of 2.6755 kilometers per second on September 9, 2025, can potentially bring the Juno spacecraft from its orbit around Jupiter to intercept the path of 3I\/ATLAS. With Juno\u2019s many instruments, a fly-by can probe the nature of 3I\/ATLAS far better than telescopes on Earth. The desired thrust constitutes a Jupiter Oberth Maneuver which requires an application of \u2206V only 8 days prior to the originally intended termination date for Juno\u2019s plunge into the atmosphere of Jupiter. Having delivered this thrust to diminish Juno\u2019s altitude, a further \u2206V is subsequently delivered, constituting a Jupiter Oberth Maneuver and resulting in an eventual intercept of the target 3I\/ATLAS on March 14, 2026. In total, an overall \u2206V of 2.1574 + 0.5181 = 2.6755 kilometers per second is utilized.<\/p>\n

If doable, this exciting new goal will rejuvenate Juno\u2019s mission and extend its scientific lifespan beyond March 14, 2026.<\/p>\n

Small corrections to Juno\u2019s path might be needed if cometary activity 3I\/ATLAS will be intensified as it comes closer to the Sun and its non-gravitational acceleration will change its expected trajectory.<\/p>\n

Over the coming decade, the Vera C. Rubin Observatory<\/a> in Chile. Is expected to discover new interstellar objects every few months. A similar approach can be taken with other spacecraft which happen to be close to their paths.<\/p>\n

ABOUT THE AUTHOR<\/strong><\/p>\n

Zoom image will be displayed\"\"(Image Credit: Chris Michel, National Academy of Sciences, 2023)<\/p>\n

Avi Loeb<\/strong> is the head of the Galileo Project, founding director of Harvard University\u2019s \u2014 Black Hole Initiative, director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics, and the former chair of the astronomy department at Harvard University (2011\u20132020). He is a former member of the President\u2019s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of \u201cExtraterrestrial:<\/a> The First Sign of Intelligent Life Beyond Earth<\/a>\u201d and a co-author of the textbook \u201cLife in the Cosmos<\/a>\u201d, both published in 2021. The paperback edition of his new book, titled \u201cInterstellar<\/a>\u201d, was published in August 2024.<\/p>\n","protected":false},"excerpt":{"rendered":"Zoom image will be displayedThe Juno spacecraft. (Image credit: NASA) The interstellar object 3I\/ATLAS was discovered on July…\n","protected":false},"author":3,"featured_media":100957,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[24],"tags":[159,783,67,132,68],"class_list":{"0":"post-100956","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-space","8":"tag-science","9":"tag-space","10":"tag-united-states","11":"tag-unitedstates","12":"tag-us"},"share_on_mastodon":{"url":"https:\/\/pubeurope.com\/@us\/114934222263376361","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/posts\/100956","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/comments?post=100956"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/posts\/100956\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/media\/100957"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/media?parent=100956"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/categories?post=100956"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/tags?post=100956"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}