Astronomy Picture of the Day [1]Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2025 July 7 [2]A drawing of our Solar System shows the orbits of Jupiter and interior planets. A white line shows the trajectory of passing comet 3I/ATLAS. Please see the explanation for more detailed information. Interstellar Comet 3I/ATLAS Image Credit: [3]NASA, [4]JPL-Caltech Explanation: It came from outer space. An object from outside [5]our Solar System is now passing through at high speed. Classified as a comet because of its gaseous coma, [6]3I/ATLAS is [7]only [8]the third identified macroscopic object as being [9]so alien. The comet's trajectory is shown in white on the [10]featured map, where the orbits of [11]Jupiter, [12]Mars, and [13]Earth are shown in gold, red, and blue. Currently [14]Comet 3I/ATLAS is about the distance of Jupiter from the Sun -- but closing, with its closest approach to our Sun expected to be within the orbit of [15]Mars in late October. Expected to pass near both Mars and Jupiter, [16]3I/ATLAS is not expected to pass close to the Earth. The origin of Comet 3I/ATLAS [17]remains unknown. Although initial activity indicates a [18]relatively normal comet, future observations about [19]3I/ATLAS' composition and nature will surely continue. Piece it All Together: [20]Astronomy Puzzle of the Day Tomorrow's picture: stellar sisters __________________________________________________________________ [21]< | [22]Archive | [23]Submissions | [24]Index | [25]Search | [26]Calendar | [27]RSS | [28]Education | [29]About APOD | [30]Discuss | [31]> __________________________________________________________________ Authors & editors: [32]Robert Nemiroff ([33]MTU) & [34]Jerry Bonnell ([35]UMCP) NASA Official: Amber Straughn [36]Specific rights apply. [37]NASA Web Privacy, [38]Accessibility, [39]Notices; A service of: [40]ASD at [41]NASA / [42]GSFC, [43]NASA Science Activation & [44]Michigan Tech. U. References 1. https://apod.nasa.gov/apod/archivepix.html 2. https://apod.nasa.gov/apod/image/2507/Interstellar3I_nasa_2913.jpg 3. https://www.nasa.gov/ 4. https://www.jpl.nasa.gov/ 5. https://science.nasa.gov/solar-system/ 6. https://en.wikipedia.org/wiki/3I/ATLAS 7. https://apod.nasa.gov/apod/ap171122.html 8. https://apod.nasa.gov/apod/ap191018.html 9. https://www.swri.org/newsroom/press-releases/ibex-spacecraft-measures-alien-particles-outside-solar-system-reveals-interactions-surrounding-regions 10. https://commons.wikimedia.org/wiki/File:3I-ATLAS_trajectory_Jul_2025.jpg 11. https://science.nasa.gov/jupiter/ 12. https://apod.nasa.gov/apod/ap240909.html 13. https://apod.nasa.gov/apod/ap130331.html 14. https://www.esa.int/Space_Safety/Planetary_Defence/ESA_tracks_rare_interstellar_comet 15. https://science.nasa.gov/mars/ 16. https://science.nasa.gov/solar-system/comets/3i-atlas/ 17. https://cdn.pixabay.com/photo/2019/09/04/08/24/cat-4451003_1280.jpg 18. https://apod.nasa.gov/apod/ap250128.html 19. https://youtu.be/-vzafaw0t08 20. https://www.scigames.org/apps/webjigsaw2/index.php 21. https://apod.nasa.gov/apod/ap250706.html 22. https://apod.nasa.gov/apod/archivepix.html 23. https://apod.nasa.gov/apod/lib/apsubmit2015.html 24. https://apod.nasa.gov/apod/lib/aptree.html 25. https://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search 26. https://apod.nasa.gov/apod/calendar/allyears.html 27. https://apod.com/feed.rss 28. https://apod.nasa.gov/apod/lib/edlinks.html 29. https://apod.nasa.gov/apod/lib/about_apod.html 30. https://asterisk.apod.com/discuss_apod.php?date=250707 31. https://apod.nasa.gov/apod/ap250708.html 32. http://www.phy.mtu.edu/faculty/Nemiroff.html 33. http://www.phy.mtu.edu/ 34. https://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/bonnell.html 35. http://www.astro.umd.edu/ 36. https://apod.nasa.gov/apod/lib/about_apod.html#srapply 37. https://www.nasa.gov/about/highlights/HP_Privacy.html 38. https://www.nasa.gov/general/accessibility/ 39. https://www.nasa.gov/privacy/ 40. https://astrophysics.gsfc.nasa.gov/ 41. https://www.nasa.gov/ 42. https://www.nasa.gov/centers/goddard/ 43. https://science.nasa.gov/learners 44. http://www.mtu.edu/