Astronomy:25143 Itokawa

From HandWiki
Short description: Near-Earth asteroid in the Apollo group
25143 Itokawa
Image of Itokawa from the Hayabusa spacecraft
Image of Itokawa from the Hayabusa spacecraft
Discovery[1]
Discovered byLINEAR
Discovery siteLincoln Lab's ETS
Discovery date26 September 1998
Designations
(25143) Itokawa
Pronunciation/ˌtˈkɑːwə/
Japanese: [itoꜜkawa]
Named afterHideo Itokawa[2]
1998 SF36
Minor planet category
Orbital characteristics[3]
Epoch 27 April 2019 (JD 2458600.5)
Uncertainty parameter 0
Observation arc20.38 yr (7,443 d)
|{{{apsis}}}|helion}}1.6951 AU
|{{{apsis}}}|helion}}0.9532 AU
1.3241 AU
Eccentricity0.2801
Orbital period1.52 yr (557 d)
Mean anomaly288.88°
Mean motion0° 38m 48.48s / day
Inclination1.6214°
Longitude of ascending node69.081°
162.82°
Earth MOID0.0131 AU (5.10 LD)
Physical characteristics
Dimensions535 m × 294 m × 209 m[4]
Mean diameter313 m[5]
330 m[3]
350 m[6][7]
Mass(3.51±0.105)×1010 kg[4]
(3.58±0.18)×1010 kg[8]
Mean density1.9±0.13 g/cm3[4]
1.95±0.14 g/cm3[8]
Rotation period12.132 h[6][9]
Geometric albedo0.23[7]
0.283±0.116[5]
0.36±0.22[10]
0.53[11]
Absolute magnitude (H)18.61[14] · 18.95 (R)[15]
19.00[13] · 19.2[1][3]
19.48[6][7] · 19.51±0.09[5]


25143 Itokawa (provisional designation 1998 SF36) is a sub-kilometer near-Earth object of the Apollo group and a potentially hazardous asteroid. It was discovered by the LINEAR program in 1998 and later named after Japanese rocket engineer Hideo Itokawa.[1] The peanut-shaped S-type asteroid has a rotation period of 12.1 hours and measures approximately 330 meters (1,100 feet) in diameter. Due to its low density and high porosity, Itokawa is considered to be a rubble pile, consisting of numerous boulders of different sizes rather than of a single solid body.

It was the first asteroid to be the target of a sample return mission, the Japanese space probe Hayabusa, which collected more than 1500 regolith dust particles from the asteroid's surface in 2005. After its return to Earth in 2010, the mineralogy, petrography, chemistry, and isotope ratios of these particles have been studied in detail, providing insights into the evolution of the Solar System. Itokawa was the smallest asteroid to be photographed and visited by a spacecraft prior to the DART mission to Dimorphos in 2022.

Discovery and naming

Itokawa was discovered on 26 September 1998 by astronomers with the Lincoln Near-Earth Asteroid Research (LINEAR) program at Lincoln Laboratory's Experimental Test Site near Socorro, New Mexico, in the United States. It was given the provisional designation 1998 SF36. The body's observation arc begins with its first observation by the Sloan Digital Sky Survey just one week prior to its official discovery observation.[1] The minor planet was named in memory of Japanese rocket scientist Hideo Itokawa (1912–1999), who is regarded as the father of Japanese rocketry.[1][16] The official naming citation was published by the Minor Planet Center on 6 August 2003 (M.P.C. 49281).[17]

Orbit and classification

Itokawa belongs to the Apollo asteroids. They are Earth-crossing asteroids and the largest dynamical group of near-Earth objects with nearly 10,000 known members. Itokawa orbits the Sun at a distance of 0.95–1.70 AU once every 18 months (557 days; semi-major axis of 1.32 AU). Its orbit has an eccentricity of 0.28 and an inclination of 2° with respect to the ecliptic.[3] It has a low Earth minimum orbital intersection distance of 0.0131 AU (1,960,000 km), which corresponds to 5.1 lunar distances.[3]

Left: orbital diagram of Itokawa on December 2006. Right: animated orbits of Itokawa (green) and Earth (blue) around the Sun.

Exploration

File:Artist’s impression of asteroid (25143) Itokawa.ogv

In 2000, it was selected as the target of Japan's Hayabusa mission. The probe arrived in the vicinity of Itokawa on 12 September 2005 and initially "parked" in an asteroid–Sun line at 20 km (12 mi), and later 7 km (4.3 mi), from the asteroid (Itokawa's gravity was too weak to provide an orbit, so the spacecraft adjusted its orbit around the Sun until it matched the asteroid's). Hayabusa landed on 20 November for thirty minutes, but it failed to operate a device designed to collect soil samples. On 25 November, a second landing and sampling sequence was attempted. The sample capsule was returned to Earth and landed at Woomera, South Australia on 13 June 2010, around 13:51 UTC (23:21 local). On 16 November 2010, the Japan Aerospace Exploration Agency reported that dust collected during Hayabusa's voyage was indeed from the asteroid.[18]

Surface features

Names of major surface features were proposed by Hayabusa scientists and accepted by the Working Group for Planetary System Nomenclature of the International Astronomical Union.[16] Also, the Hayabusa science team is using working names for smaller surface features.[19][20] The following tables list the names of geological features on the asteroid.[16] No naming conventions have been disclosed for surface features on Itokawa.

Craters

Ten impact craters on the surface of Itokawa were named on 18 February 2009.[21]

Regio Coordinates Diameter (km) Approval Date Named After Ref
Catalina [ ⚑ ] 17°S 14°E / 17°S 14°E / -17; 14 (Catalina) 0.02 2009 Catalina Station (astronomical observatory) in Arizona, United States WGPSN
Fuchinobe [ ⚑ ] 34°N 91°W / 34°N 91°W / 34; -91 (Fuchinobe) 0.04 2009 Fuchinobe in Sagamihara, Japan WGPSN
Gando [ ⚑ ] 76°S 155°W / 76°S 155°W / -76; -155 (Gando) n.a. 2009 Gando, Canary Islands; Spanish launch facility WGPSN
Hammaguira [ ⚑ ] 18°S 155°W / 18°S 155°W / -18; -155 (Hammaguira) 0.03 2009 Hammaguir, Algeria; abandoned French launch site and missile testing range in the Sahara desert WGPSN
Kamisunagawa [ ⚑ ] 28°S 45°E / 28°S 45°E / -28; 45 (Kamisunagawa) 0.01 2009 Kamisunagawa, town in Hokkaido Japan, where a microgravity test facility is located WGPSN
Kamoi [ ⚑ ] 6°N 116°W / 6°N 116°W / 6; -116 (Kamoi) 0.01 2009 Japanese town of Kamoi in Yokohama, location of the NEC Toshiba Space Systems Ltd. factory WGPSN
Komaba [ ⚑ ] 10°S 102°E / 10°S 102°E / -10; 102 (Komaba) 0.03 2009 Komaba in Meguro, Japan, where the Institute of Space and Astronautical Science is located WGPSN
Laurel [ ⚑ ] 1°N 162°E / 1°N 162°E / 1; 162 (Laurel) 0.02 2009 U.S. city of Laurel in Maryland, where APL/JHU is located WGPSN
Miyabaru [ ⚑ ] 40°S 116°W / 40°S 116°W / -40; -116 (Miyabaru) 0.09 2009 Radar site of the Uchinoura Space Center in Japan WGPSN
San Marco [ ⚑ ] 28°S 41°W / 28°S 41°W / -28; -41 (San Marco) n.a. 2009 San Marco platform, an old oil platform near Kenya that served as a launch pad for Italian spacecraft WGPSN

Regiones

Regio or regiones are large area marked by reflectivity or color distinctions from adjacent areas in planetary geology. The following regiones have been named on Itokawa.[16][21]

Regio Coordinates Diameter (km) Approval Date Named After Ref
Arcoona Regio [ ⚑ ] 28°N 202°E / 28°N 202°E / 28; 202 (Arcoona) 0.16 Feb. 18, 2009 Arcoona, Australia WGPSN
LINEAR Regio [ ⚑ ] 40°S 232°E / 40°S 232°E / -40; 232 (LINEAR) 0.12 Feb. 18, 2009 Lincoln Near-Earth Asteroid Research WGPSN
MUSES-C Regio [ ⚑ ] 70°S 60°E / 70°S 60°E / -70; 60 (MUSES-C) 0.3 2006 MUSES-C, name of the Hayabusa probe prior to launch WGPSN
Ohsumi Regio [ ⚑ ] 33°N 207°E / 33°N 207°E / 33; 207 (Ohsumi) 0.14 Feb. 18, 2009 Ōsumi Peninsula WGPSN
Sagamihara Regio [ ⚑ ] 80°N 15°E / 80°N 15°E / 80; 15 (Sagamihara) 0.23 2006 Sagamihara, a town in Japan where Institute of Space and Astronautical Science is located WGPSN
Uchinoura Regio [ ⚑ ] 40°N 90°E / 40°N 90°E / 40; 90 (Uchinoura) 0.07 2006 Uchinoura, a town in Japan (now part of Kimotsuki), the location of Uchinoura Space Center, Hayabusa launch site WGPSN
Yoshinobu Regio [ ⚑ ] 39°S 117°E / 39°S 117°E / -39; 117 (Yoshinobu) 0.16 Feb. 18, 2009 Launch site in the Tanegashima Space Center, Japan WGPSN

Physical characteristics

Schematic of Itokawa's two lobes separated from each other. Their divergent densities suggest that these were stand-alone bodies that came into contact later on, making the rubble pile also a likely contact binary.[22]
Preliminary shape model of Itokawa based on radar observations by Goldstone and Arecibo[23]

Itokawa is a stony S-type asteroid. Radar imaging by Goldstone in 2001 observed an ellipsoid 630±60 meters long and 250±30 meters wide.[23]

The Hayabusa mission confirmed these findings and also suggested that Itokawa may be a contact binary formed by two or more smaller asteroids that have gravitated toward each other and stuck together. The Hayabusa images show a surprising lack of impact craters and a very rough surface studded with boulders, described by the mission team as a rubble pile.[4][24] Furthermore, the density of the asteroid is too low for it to be made from solid rock. This would mean that Itokawa is not a monolith but rather a rubble pile formed from fragments that have cohered over time. Based on Yarkovsky–O'Keefe–Radzievskii–Paddack effect measurements, a small section of Itokawa is estimated to have a density of 2.9 g/cm3, whereas a larger section is estimated to have a density of 1.8 g/cm3.[4][25]

Rotation period and poles

Since 2001, a large number of rotational lightcurves of Itokawa have been obtained from photometric observations. Analysis of the best-rated lightcurve by Mikko Kaasalainen gave a sidereal rotation period of 12.132 hours with a high brightness variation of 0.8 magnitude, indicative of the asteroid's non-spherical shape ({{{1}}}). In addition, Kaasalainen also determined two spin axes of (355.0°, −84.0°) and (39°, −87.0°) in ecliptic coordinates (λ, β).[6][9] Alternative lightcurve measurements were made by Lambert (12 h),[26] Lowry (12.1 and 12.12 h),[27][28] Ohba (12.15 h),[29] Warner (12.09 h),[30][lower-alpha 1] Ďurech (12.1323 h),[31] and Nishihara (12.1324 h).[15]

Composition

The 26 August 2011 issue of Science devoted six articles to findings based on dust that Hayabusa had collected from Itokawa.[32] Scientists' analysis suggested that Itokawa was probably made up from interior fragments of a larger asteroid that broke apart.[33] Dust collected from the asteroid surface is thought to have been exposed there for about eight million years.[32]

Scientists used varied techniques of chemistry and mineralogy to analyze the dust from Itokawa.[33] Itokawa's composition was found to match the common type of meteorites known as "low-total-iron, low metal ordinary chondrites".[34] Another team of scientists determined that the dark iron color on the surface of Itokawa was the result of abrasion by micrometeoroids and high-speed particles from the Sun which had converted the normally whitish iron oxide coloring.[34]

2018 Hayabusa results

Two separate groups report water in different Itokawa particles. Jin et al. report water in low-calcium pyroxene grains. The water's isotope level corresponds with inner Solar System and carbonaceous chondrite water isotope levels.[35] Daly et al. report "OH and H
2
O
" apparently formed by implantation of solar wind hydrogen. The rims of an olivine particle "show an enrichment of up to ~1.2 at % in OH and H2O".[36] The water concentrations of the Itokawa grains would indicate an estimated BSI (Bulk Silicate Itokawa) water content in line with Earth's bulk water, and that Itokawa had been a "water-rich asteroid".[37]

2020 Hayabusa results

At the 2020 Lunar and Planetary Science Conference, a third group reported water and organics, via a third Hayabusa particle- RA-QD02-0612, or "Amazon." Olivine, pyroxene, and albite contain water. Isotopic compositions indicate a clear extraterrestrial origin.[38]

2021 Hayabusa results

A further report by Daly's group was published which supported the theory that a large source of earth's water has come from hydrogen atoms carried on particles in the solar wind which combine with oxygen on asteroids and then arrive on earth in space dust. Using atom probe tomography the study found hydroxide and water molecules on the surface of a single grain from particles retrieved from the asteroid Itokawa by the Japanese space probe Hayabusa.[39][40]

Dust ponds are identified in the asteroid. They are a phenomenon where pockets of dust are seen in Celestial bodies without a significant atmosphere. Smooth deposits of dust accumulate in depressions on the surface of the body (like craters), contrasting from the Rocky terrain around them. [41] In the Sagamihara and Muses-Sea regions of the asteroid dust ponds were identified. Dust particles had a size varying from millimeters to less than a centimeter.

See also

Notes

  1. Lightcurve plot of (25143) Itokawa, Palmer Divide Observatory (716) by B. D. Warner (2004). Summary figures at the LCDB.

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 "25143 Itokawa (1998 SF36)". Minor Planet Center. https://www.minorplanetcenter.net/db_search/show_object?object_id=25143. 
  2. Schmadel, Lutz D. (2006). "(25143) Itokawa [1.32, 0.28, 1.6]". Dictionary of Minor Planet Names – (25143) Itokawa, Addendum to Fifth Edition: 2003–2005. Springer Berlin Heidelberg. p. 188. doi:10.1007/978-3-540-34361-5_2203. ISBN 978-3-540-34361-5. 
  3. 3.0 3.1 3.2 3.3 3.4 3.5 3.6 "JPL Small-Body Database Browser: 25143 Itokawa (1998 SF36)". Jet Propulsion Laboratory. https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2025143. 
  4. 4.0 4.1 4.2 4.3 4.4 Fujiwara, A.; Kawaguchi, J.; Yeomans, D. K.; Abe, M.; Mukai, T.; Okada, T. et al. (June 2006). "The Rubble-Pile Asteroid Itokawa as Observed by Hayabusa". Science 312 (5778): 1330–1334. doi:10.1126/science.1125841. PMID 16741107. Bibcode2006Sci...312.1330F. https://www.researchgate.net/publication/7042075. Retrieved 25 February 2019. 
  5. 5.0 5.1 5.2 Mueller, Michael; Delbo', M.; Hora, J. L.; Trilling, D. E.; Bhattacharya, B.; Bottke, W. F. et al. (April 2011). "ExploreNEOs. III. Physical Characterization of 65 Potential Spacecraft Target Asteroids". The Astronomical Journal 141 (4): 9. doi:10.1088/0004-6256/141/4/109. Bibcode2011AJ....141..109M. https://authors.library.caltech.edu/23152/1/Mueller2011p13239Astron_J.pdf. 
  6. 6.0 6.1 6.2 6.3 6.4 "LCDB Data for (25143) Itokawa". Asteroid Lightcurve Database (LCDB). http://www.minorplanet.info/PHP/generateOneAsteroidInfo.php?AstInfo=25143%7CItokawa. 
  7. 7.0 7.1 7.2 Sekiguchi, T.; Abe, M.; Boehnhardt, H.; Dermawan, B.; Hainaut, O. R.; Hasegawa, S. (January 2003). "Thermal observations of MUSES-C mission target (25143) 1998 SF36". Astronomy and Astrophysics 397: 325–328. doi:10.1051/0004-6361:20021437. Bibcode2003A&A...397..325S. 
  8. 8.0 8.1 Abe, Shinsuke; Mukai, Tadashi; Hirata, Naru; Barnouin-Jha, Olivier S.; Cheng, Andrew F.; Demura, Hirohide et al. (June 2006). "Mass and Local Topography Measurements of Itokawa by Hayabusa". Science 312 (5778): 1344–1349. doi:10.1126/science.1126272. PMID 16741111. Bibcode2006Sci...312.1344A. 
  9. 9.0 9.1 Kaasalainen, M.; Kwiatkowski, T.; Abe, M.; Piironen, J.; Nakamura, T.; Ohba, Y. et al. (July 2003). "CCD photometry and model of MUSES-C target (25143) 1998 SF36". Astronomy and Astrophysics 405 (3): L29–L32. doi:10.1051/0004-6361:20030819. Bibcode2003A&A...405L..29K. 
  10. Thomas, C. A.; Trilling, D. E.; Emery, J. P.; Mueller, M.; Hora, J. L.; Benner, L. A. M. et al. (September 2011). "ExploreNEOs. V. Average Albedo by Taxonomic Complex in the Near-Earth Asteroid Population". The Astronomical Journal 142 (3): 12. doi:10.1088/0004-6256/142/3/85. Bibcode2011AJ....142...85T. 
  11. S. M. Lederer, et al., "Physical characteristics of Hayabusa target Asteroid 25143 Itokawa", Icarus, v. 173, pp. 153–165 (2005)
  12. Thomas, Cristina A.; Emery, Joshua P.; Trilling, David E.; Delbó, Marco; Hora, Joseph L.; Mueller, Michael (January 2014). "Physical characterization of Warm Spitzer-observed near-Earth objects". Icarus 228: 217–246. doi:10.1016/j.icarus.2013.10.004. Bibcode2014Icar..228..217T. 
  13. 13.0 13.1 Carry, B.; Solano, E.; Eggl, S.; DeMeo, F. E. (April 2016). "Spectral properties of near-Earth and Mars-crossing asteroids using Sloan photometry". Icarus 268: 340–354. doi:10.1016/j.icarus.2015.12.047. Bibcode2016Icar..268..340C. 
  14. Dermawan, Budi; Nakamura, Tsuko; Fukushima, Hideo; Sato, Hideo; Yoshida, Fumi; Sato, Yusuke (August 2002). "CCD Photometry of the MUSES-C Mission Target: Asteroid (25143) 1998 SF36". Publications of the Astronomical Society of Japan 54 (4): 635–640. doi:10.1093/pasj/54.4.635. Bibcode2002PASJ...54..635D. 
  15. 15.0 15.1 Nishihara, S.; Abe, M.; Hasegawa, S.; Ishiguro, M.; Kitazato, K.; Miura, N. et al. (March 2005). "Ground-based Lightcurve Observation of (25143) Itokawa, 2001–2004". 36th Annual Lunar and Planetary Science Conference 36: 1833. Bibcode2005LPI....36.1833N. 
  16. 16.0 16.1 16.2 16.3 "Official Approval of Names on Itokawa by IAU". Press Release of JAXA. 3 March 2009. http://global.jaxa.jp/press/2009/03/20090303_itokawa_e.html. 
  17. "MPC/MPO/MPS Archive". Minor Planet Center. https://www.minorplanetcenter.net/iau/ECS/MPCArchive/MPCArchive_TBL.html. 
  18. Atkinson, Nancy (16 November 2010). "Confirmed: Hayabusa Nabbed Asteroid Particles". Universe Today. http://www.universetoday.com/78895/confirmed-hayabusa-nabbed-asteroid-particles/. 
  19. "Itowaka Geological Map". http://www.isas.jaxa.jp/e/snews/2006/image/0602/b/08.jpg. 
  20. "Local site names on Itowaka". http://www.isas.jaxa.jp/e/snews/2006/image/0602/b/09.jpg. 
  21. 21.0 21.1 "Planetary Names: Itokawa". Gazetteer of Planetary Nomenclature – USGS Astrogeology Research Program. https://planetarynames.wr.usgs.gov/Page/ITOKAWA/target. 
  22. "The Anatomy of an Asteroid". ESO Press Release. http://www.eso.org/public/news/eso1405/. 
  23. 23.0 23.1 Ostro, S. J.; Benner, L. A. M.; Nolan, M. C.; Giorgini, J. D.; Jurgens, R. F.; Rose, R. et al. (November 2001). "Radar Observations of Asteroid 25143 (1998 SF36)". American Astronomical Society 33: 1117. Bibcode2001DPS....33.4113O. http://echo.jpl.nasa.gov/asteroids/Itokawa/ostro.etal.2004.itokawa.pdf. Retrieved 25 February 2019. 
  24. "Hayabusa: Itokawa Beckons as Japan's Spacecraft Searches for Places to Touch Down". http://www.planetary.org/news/2005/0916_Hayabusa_Itokawa_Beckons_as_Japans.html. 
  25. "The Anatomy of an Asteroid". ESO. 5 February 2014. http://www.eso.org/public/news/eso1405/. 
  26. Lambert, J. S.; Tholen, D. J. (December 2001). "Rotational Studies of MUSES-C Target Asteroid (25143) 1998 SF36". American Astronomical Society 33: 1402. Bibcode2001AAS...199.6303L. 
  27. Lowry, S. C.; Weissman, P. R.; Hicks, M. D. (November 2001). "CCD Observations of Asteroid 1998 SF36 (25143)". American Astronomical Society 33: 1150. Bibcode2001DPS....33.5909L. 
  28. Lowry, Stephen C.; Weissman, Paul R.; Hicks, Michael D.; Whiteley, Robert J.; Larson, Steve (August 2005). "Physical properties of Asteroid (25143) Itokawa – Target of the Hayabusa sample return mission". Icarus 176 (2): 408–417. doi:10.1016/j.icarus.2005.02.002. Bibcode2005Icar..176..408L. 
  29. Ohba, Y.; Abe, M.; Hasegawa, S.; Ishiguro, M.; Kwiatkowski, T.; Colas, F. et al. (June 2003). "Pole orientation and triaxial ellipsoid shape of (25143) 1998 SF36, a target asteroid of the MUSES-C* mission". Earth 55 (6): 341–347.(EP&SHomepage). doi:10.1186/BF03351767. Bibcode2003EP&S...55..341O. 
  30. Warner, Brian D. (September 2004). "Lightcurve analysis for numbered asteroids 301, 380, 2867, 8373, 25143, and 31368". The Minor Planet Bulletin 31 (3): 67–70. ISSN 1052-8091. Bibcode2004MPBu...31...67W. 
  31. Durech, J.; Vokrouhlický, D.; Kaasalainen, M.; Weissman, P.; Lowry, S. C.; Beshore, E. et al. (September 2008). "New photometric observations of asteroids (1862) Apollo and (25143) Itokawa – an analysis of YORP effect". Astronomy and Astrophysics 488 (1): 345–350. doi:10.1051/0004-6361:200809663. Bibcode2008A&A...488..345D. 
  32. 32.0 32.1 "Asteroid Dust Confirms Meteorite Origins". The New York Times. 25 August 2011. https://www.nytimes.com/2011/08/30/science/30obmeteor.html. 
  33. 33.0 33.1 Nakamura, Tomoki; Noguchi, Takaaki; Tanaka, Masahiko; Zolensky, Michael E.; Kimura, Makoto; Tsuchiyama, Akira et al. (August 2011). "Itokawa Dust Particles: A Direct Link Between S-Type Asteroids and Ordinary Chondrites". Science 333 (6046): 1113–1116. doi:10.1126/science.1207758. PMID 21868667. Bibcode2011Sci...333.1113N. 
  34. 34.0 34.1 "Most Earth meteorites linked to single asteroid". Los Angeles Times. 26 August 2011. http://www.latimes.com/news/science/la-sci-asteroid-meteorites-20110826,0,4632492.story. 
  35. Jin, Z. L.; Bose, M.; Peeters, Z. (March 2018). "New Clues to Ancient Water on Itokawa". 49th Lunar and Planetary Science Conference. pp. 1670. Bibcode2018LPI....49.1670J. https://www.hou.usra.edu/meetings/lpsc2018/pdf/1670.pdf. Jin, Ziliang; Bose, Maitrayee (2019). "New clues to ancient water on Itokawa". Science Advances (American Association for the Advancement of Science (AAAS)) 5 (5): eaav8106. doi:10.1126/sciadv.aav8106. ISSN 2375-2548. PMID 31114801. Bibcode2019SciA....5.8106J. 
  36. Daly, LExpression error: Unrecognized word "et". (2018). "The origin of hydrogen in space weathered rims of Itokawa regolith particles". 2018 Hayabusa Symposium. https://curation.isas.jaxa.jp/symposium/abstract/2018/1206_1015_Luke_Daly.pdf. 
  37. Jin Z; Bose M (2018). "Establishing Itokawa's water contribution to Earth". 2018 Hayabusa Symposium. https://curation.isas.jaxa.jp/symposium/abstract/2018/1206_1000_Ziliang_Jin.pdf. 
  38. Chan, Q; Brunetto, R; Kebukawa, Y; Noguchi, T; Stephant, A; Franchi, I; Zhao, X; Johnson, D et al. (2020). "First Identification of Indigenous Organic Matter Alongside Water In Itokawa Particle Returned By The Hayabusa Mission". 51st LPSC.  Sec. H2O abundance and isotopic composition
  39. Daly, Luke; Lee, Martin R.; Hallis, Lydia J.; Ishii, Hope A.; Bradley, John P.; Bland, Phillip. A.; Saxey, David W.; Fougerouse, Denis et al. (December 2021). "Solar wind contributions to Earth's oceans". Nature Astronomy 5 (12): 1275–1285. doi:10.1038/s41550-021-01487-w. http://eprints.gla.ac.uk/244833/3/244833.pdf. 
  40. Daly, Luke; Lee, Martin R.; Timms, Nick; Bland, Phil (November 30, 2021). "Up to half of Earth's water may come from solar wind and space dust". https://phys.org/news/2021-11-earth-solar-space.html. 
  41. "Eros's puzzling surface". https://skyandtelescope.org/astronomy-news/eross-puzzling-surface/. Retrieved 18 October 2023. 

Further reading

External links