Each time around the orbit, Dimorphos passes through the shadow cast by Didymos, and half an orbit later, briefly casts a shadow onto Didymos. These times are when the flux is at half the total reduction in flux during the event (Fig. and M. Brozovi assisted with proposal writing, observing and data processing for the radar observations. Consider supporting ScienceX's mission by getting a premium account. Credit: ESA - European Space Agency. Now, based on ground-based telescope observations, Dimorphos So the pair will be released from Hera at a velocity of just a few centimeters per secondany faster and they would risk escaping the asteroid's feeble gravity and being lost in space. Previous observations of the Didymos system4 demonstrated the need for requirements on the photometry used in the analysis. Mon. Dimorphos, measuring 160 meters (525 feet) in diameter, is the perfect target for the DART test because of its orbit around the larger main body Didymos (which measures 780 meters, or 0.48 miles, in diameter), and because of the pairs relatively close proximity to Earth in late 2022. The Orbit of Asteroid Didymos - NASA Jet Propulsion CAS J. Asteroid lost 1 million kilograms after collision with DART - Nature This site uses cookies to assist with navigation, analyse your use of our services, collect data for ads personalisation and provide content from third parties. The asteroid Dimorphos had its 12-hour orbit shortened by a half-hour. This orbital diagram was produced by the Center for Near Earth Object Studies (CNEOS), which is managed by NASAs Jet Propulsion Laboratory in Southern California. Sci. 471, 29743007 (2017). Nasa Dart asteroid spacecraft: Mission to smash into Dimorphos Medical research advances and health news, The latest engineering, electronics and technology advances, The most comprehensive sci-tech news coverage on the web. Asteroid lost 1 million kilograms after collision with DART - Nature We determined its 3 uncertainty as an interval in which 2 is below a certain limit. These results made use of the Lowell Discovery Telescope (LDT) at Lowell Observatory. On 9 October, the ellipse spans 980m to +980m along the y axis and 8Hz to +8Hz along the x axis, corresponding to line-of-sight velocity of 14cms1 to +14cms1. The missions primary goal was to change the orbital period of Dimorphos, the time it takes the moon to orbit Didymos. Astron. Icarus 364, 114387 (2021). 6 to estimate the uncertainty of the post-impact period. We keep our content available to everyone. Nature In 2003, it passed only 0.048 AU from 4. This work was supported by the DART mission, NASA Contract No. How will we find the right asteroid? NEOExchange - an online portal for NEO and Solar System science. Planet. The Double Asteroid Redirection Test (DART) spacecraft successfully performed the first test of a kinetic impactor for asteroid deflection by impacting Dimorphos, the Northern Arizona University, Flagstaff, AZ, USA, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA, Shantanu P. Naidu,Steven R. Chesley,Lance A. M. Benner,Marina Brozovi,Declan Mages,Jon D. Giorgini,Brian Rush&Julie Bellerose, Astronomical Institute of the Czech Academy of Sciences, Ondejov, Czech Republic, Peter Scheirich,Petr Pravec,Peter Kunirk&Kamil Hornoch, Nicholas A. Moskovitz,Brian Skiff&Tom Polakis, Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA, Andrew S. Rivkin,Nancy L. Chabot&Andrew F. Cheng, Carnegie Institution for Science, Las Campanas Observatory, La Serena, Chile, David J. Osip,Carlos Contreras&Nidia Morrell, Tim A. Lister,Joseph Chatelain,Edward Gomez&Liz Phillips, University of Edinburgh, Royal Observatory, Edinburgh, UK, Agata Roek,Colin Snodgrass&Mariangela Bonavita, National Radio Astronomy Observatory, Charlottesville, VA, USA, Green Bank Observatory, Green Bank, WV, USA, Andrew D. Seymour,Pedro Salas,William P. Armentrout&Galen Watts, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark, United States Naval Academy, Annapolis, MD, USA, University of Maryland, College Park, MD, USA, Tony L. Farnham,Carrie E. Holt&Harrison F. Agrusa, University of Washington, Seattle, WA, USA, University of California, Santa Barbara, Santa Barbara, CA, USA, Seoul National University, Gwanak-gu, Seoul, Korea, Universidad de Antofagasta, Antofagasta, Chile, Universidad Catlica de la Santsima Concepcin, Concepcin, Chile, Isfahan University of Technology, Isfahan, Iran, Magdalena Ridge Observatory, New Mexico Institute of Mining and Technology, Socorro, NM, USA, You can also search for this author in Radar observations and a physical model of binary near-Earth asteroid 65803 Didymos, target of the DART mission. The fact that Dimorphos orbits Didymos every 11.92 hours means that any small change in its orbit caused by the impact can be effectively observed and quantified DOI: 10.48550/arxiv.2303.07333, Journal information: in AAS/Division for Planetary Sciences Meeting Abstracts Vol. We define the primary/secondary occultation or eclipse based on which object is being obscured or shadowed, respectively. Two independent methods were used to model the available data for determination of the post-impact orbital period: (1) we use the processes described in ref. NASAs DART successfully impacted Dimorphos, the secondary of the near-Earth binary asteroid (65803) Didymos, on 26 September 2022 at 23:14 UTC. Using new Earth-based lightcurve and radar observations, two independent approaches determined identical values for the change in the orbital period. telescope and of the Irenee DuPont telescope at Las Campanas Observatory, Chile. These positions were mapped from image coordinates into right ascension (RA) and declination (DEC) using the camera model and the GNC (guidance, navigation and control) spacecraft attitude knowledge. Thomas, C.A., Naidu, S.P., Scheirich, P. et al. Mod. The models incorporated three types of observation of the DidymosDimorphos system: photometric lightcurves, radar, and Didymos-relative astrometry from the DRACO camera aboard DART20. The information you enter will appear in your e-mail message and is not retained by Phys.org in any form. Use this form if you have come across a typo, inaccuracy or would like to send an edit request for the content on this page. Both approaches determined a statistically identical pre-impact orbital period of 11.921480.00013(3)h. To determine the post-impact orbital period, we obtained radar and lightcurve observations of the Didymos system. These observations were scheduled and reduced using the NEOexchange Target and Observation Manager and data-reduction pipeline29. Raducan, S. D. & Jutzi, M. Global-scale reshaping and resurfacing of asteroids by small-scale impacts, with applications to the DART and Hera missions. Nature thanks the anonymous reviewers for their contribution to the peer review of this work. Saunders, E. S., Lampoudi, S., Lister, T. A., Norbury, M. & Walker, Z. in Observatory Operations: Strategies, Processes, and Systems V (eds Peck, A. However, we do not guarantee individual replies due to the high volume of messages. Soc. Researchers expect the impact to shorten Dimorphos orbit by about 1%, or roughly 10 minutes; precisely measuring how much the asteroid was deflected is one of the primary the following attributes while ensuring the content's credibility: The team working on ESA's Hera asteroid mission has glimpsed its destination. Imagine Walking on Heras Asteroid - Technology Org Additionalreductions of these data with optimized apertures will be used to address these discrepancies. Thank you for visiting nature.com. 65803 Didymos - Wikipedia The Double Asteroid Redirection Test (DART) spacecraft successfully performed the first test of a kinetic impactor for asteroid deflection by impacting Dimorphos, the secondary of near-Earth binary asteroid (65803) Didymos, and changing the orbital period of Dimorphos. The DRACO images can be found in an archive associated with the Daly et al. At the time these measurements were made, no shape models estimated from spacecraft images were available to fit to the partially illuminated figures of the two bodies, so we measured the intersections of the limbs with the relative position vectors. We used differential corrections as described in ref. Dimorphos can be seen when illuminated by radar and the system was never in a radar eclipse geometry. Sci. 6 and that we have revised using the extra data taken in July 2022. The authors declare no competing interests. 15). We used the 1-m telescopes at the South Africa and Chile nodes with the telescopes tracking at half of the ephemeris rates. By using this mathematical representation for the system, we assume that Didymos is in principal-axis rotation, that mutual illumination between the objects is negligible and that the rotational lightcurve does not change with time. 17,37 and discussed in ref. Exposures were taken with a broad VR-band filter. The primary objective of DART was to change the orbital period of Dimorphos around Didymos to demonstrate that a kinetic impactor is a viable method of asteroid deflection1,7. 3, 175 (2022). The post-impact system was analysed with no a priori assumption on the new binary orbital period. "The boulders covering the surface of Dimorphos are much bigger than they might look," says planetary scientist Naomi Murdoch of ISAE-Supaero in France, working on the CubeSat landings. The SP22 approach models the lightcurve observations to determine the properties of the orbit. Please select the most appropriate category to facilitate processing of your request. acknowledges funding from the Novo Nordisk Foundation Interdisciplinary Synergy Programme grant no. Dimorphos, at 160 m across is about the same size as the Great Pyramid of Giza, orbiting around the mountain sized Didymos asteroid, about 780-m across. 3, 206 (2022). You can unsubscribe at any time and we'll never share your details to third parties. The initial orbit of Dimorphos was first defined following the 2003 apparition when the secondary was discovered11,17. One thing they've learned is that it's spinning, and quite quickly, completing one full rotation every 2 hours and 16 minutes. In the meantime, to ensure continued support, we are displaying the site without styles Google Scholar. NNF19OC0057374 and from the European Union H2020-MSCA-ITN-2019 grant no. NASA spacecraft successfully collides with asteroid - ABC News The LCOGT network27 consists of telescopes at seven sites around the world, operated robotically using dynamical scheduling software28. The VizieR database of astronomical catalogues. supported orbit estimation of Dimorphos. Dimorphos W.H.R. You can unsubscribe at any time and we'll never share your details to third parties. For NASA to consider DART a success, the impact will need to shorten Dimorphoss orbit around Didymos by at least 73 seconds. The lightcurve data are corrected to constant geocentric and heliocentric distances and a consistent solar phase angle. Planet. Gaia Data Release 3: the Galaxy in your preferred colours. J. Because the reflex motion of Didymos about the system barycentre is <10m (0.08Hz)11, we assumed that the Didymos centre of mass (COM) is at 0Hz, so that the Doppler frequency of Dimorphos represents the relative Doppler shift. Nov. 17, 2021. The mutual event times are highly consistent across these datasets, although residual systematics in the photometry result in slightly different event depths. We used n to capture the change in mean motion owing to the DART impact. DART's impact with the Dimorphos asteroid shifted its orbit around Didymos as well as casting debris thousands of kilometers across space. WebDidymos orbits the Sun at a distance of 1.02.3 AU once every 770 days (2 years and 1 month). There are no issues on the timing of the events, which are the key drivers for the derivation of the new orbit period. The goal is to speed up Dimorphoss orbit, cutting the time it takes to travel around Didymos by 1015 minutes (see Destructive manoeuvre). DARTs During the secondary eclipse, Dimorphos is completely shadowed. P.A.T., A.D.S., P. Salas, W.P.A. Interestingly, large objects tend to stay afloat longer than small ones. J. Fahnestock, E. G. et al. The rapidly changing EarthDidymosSun geometry during this period ofDidymos close approach to Earth causes observable changes in the primary rotational lightcurve. After DART: using the first full-scale test of a kinetic impactor to inform a future planetary defense mission. The rotation period of Didymos is measured during the lightcurve analysis process and shows no variation from its pre-impact value of 2.260h to an uncertainty of approximately 5s (3). Prediction uncertainties are smaller than the resolution of the spectra. 3, 183 (2022). "You would want to avoid contact with surface rocks while gliding however, as they are likely to be sharp enough to snag your spacesuit, having never been smoothed by water or wind," says Naomi. We are planning the ambitious Hera asteroid deflection mission. At those speeds, Didymos is an asteroid "on the edge of stability," according to a recent preprint published on ArXiv. Cheng, A. F. et al. It became more difficult to detect Dimorphos after 4 October, as the distance to Didymos increased and the SNRs correspondingly decreased. Next, in October 2024, ESA's Hera mission will begin its own journey to Dimorphos, to gather close-up data including the size of the impact crater and the asteroid's mineral make-up and mass. ADS 616, A1 (2018). We attempted imaging with time delay resolutions of 0.5s and 1s (corresponding to range resolutions of 75m and 150m) and found that the 0.5-s setup yielded more consistent detections. J 143, 24 (2012). On average, our data have photometric accuracy of root mean square (RMS) about 0.006magnitudes. The motion of the two bodies is assumed to be Keplerian. NASA Astron. That heat is later radiated away, producing thrust. Didymos A change in orbital period of approximately 7min was expected if the incident momentum from the DART spacecraft was directly transferred to the asteroid target in a perfectly inelastic collision1, but studies of the probable impact conditions and asteroid properties indicated that a considerable momentum enhancement () was possible2,3. Advertisement. Effects of impact and target parameters on the results of a kinetic impactor: predictions for the Double Asteroid Redirection Test (DART) mission. led the data collection from the Las Cumbres Observatory Global Telescope network. B., Benn, C. R. & Seaman, R. L.) 91490E (SPIE, 2014). E.K. NASAs DART Mission Successfully Crashed Into Didymos Moon This large orbit period change suggests that ejecta contributed a substantial amount of momentum to the asteroid beyond what the DART spacecraft carried. The telescope was tracked at half of the ephemeris rate. The Double Asteroid Redirect Test (DART) mission was officially a success. As the two asteroids orbit the sun, Dimorphos also orbits Didymos, circling its larger twin every 11 hours and 55 minutes. Nature (2023). For an accurate decomposition of the lightcurve, we require adequate coverage of the primary lightcurve outside mutual events. We connect data from different telescopes by scaling them in relative magnitude compared with each other, which has no impact on the timing of the mutual events. In 2003, it passed only 0.048 AU from Earth. To model the photometric data of the binary asteroid system, we follow the decomposition methods defined in refs. The current estimate is that Pravec, P. et al. Dimorphos, at 160 m across is about the same size as the Great Pyramid of Giza, orbiting around the mountain sized Didymos asteroid, about 780-m across. 870403 (NEOROCKS). Astrophys. Icarus 181, 6393 (2006). The data collected suggests that Didymos is actively throwing material out into space, and there are likely millions of other small asteroids doing the same across the solar system, all the time. A satellite orbit drift in binary near-Earth asteroids (66391) 1999 KW4 and (88710) 2001 SL9 indication of the BYORP effect. Article J. Didymos: The Monster Companion Asteroid to Dimorphos, Target orbit When OSIRIS-REx touched down to take a sample, it sank nearly two meters into the loose surface like a child in a ball pit. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate. The minimum distance between the orbit of Earth and the orbit of Didymos is currently 0.04 AU (6.0 million km ), [1] but will change as the asteroid is perturbed. Photometric observations of the binary near-Earth asteroid (65803) Didymos in 20152021 prior to DART impact. To serve as a proof-of-concept for the kinetic impactor technique of planetary defence, DART needed to demonstrate that an asteroid could be targeted during a high-speed encounter16 and that the orbit of the target could be changed. P.L.-P. was partly funded by Programa de Iniciacin en Investigacin-Universidad de Antofagasta, INI-17-03. Instrumental aperture photometry was performed on every frame using the Python package SEP23. DARTs impact with the Dimorphos asteroid shifted its orbit around Didymos as well as casting debris thousands of kilometres across space. The green circle shows the location of the Dimorphos asteroid, which orbits the larger asteroid, Didymos, seen here as the bright line across the middle of the images. The current estimate is that The numerical model of the Didymos system in ref. Orbital period change of Dimorphos due to the DART kinetic impact. It presents no impact threat to Earth. We used these measurements in the determination of the orbital parameters of Dimorphos relative to Didymos. Planet. Lowell is a private, nonprofit institution dedicated to astrophysical research and public appreciation of astronomy and operates the LDT in partnership with Boston University, the University of Maryland, the University of Toledo, Northern Arizona University and Yale University. Didymos has been under scrutiny for a while now in preparation for DART and the European Space Agency's follow-up mission, Hera. Internet Explorer). Nair Trgolo et al, Lifted particles from the fast spinning primary of the Near-Earth Asteroid (65803) Didymos, arXiv (2023). For this dataset, separate decompositions are done for each Julian Day (JD). Hera will also deploy two 6-unit CubeSats for additional observations. googletag.cmd.push(function() { googletag.display('div-gpt-ad-1449240174198-2'); }); Last fall, when NASA's DART mission impacted Didymos' moon Dimorphos in a dramatic (and successful) attempt to change the object's orbit, DART got a quick look at the Didymos system before the probe was purposefully smashed to pieces. Because ofthe 11.9-h rotation period, a diameter of about 160m and a subradar latitude of 50 to 30 (ref. https://doi.org/10.1038/s41586-023-05805-2, DOI: https://doi.org/10.1038/s41586-023-05805-2. Ochsenbein, F., Bauer, P. & Marcout, J. Publishers note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. Astronomers have even seen asteroids rip themselves to pieces via the YORP effect, like asteroid P/2013 R3 in 2013. Relative photometry was calibrated using the procedure outlined in ref. The Danish Faint Object Spectrograph and Camera (DFOSC) instrument, with a field of view 13.713.7, was used in imaging mode. and G.W. This diagram shows the orbit of binary asteroid Didymos around the Sun. For our previous work4, we were able to combine data on the timescales of days to weeks. The Orbit of Asteroid Didymos Dunn, T. L., Burbine, T. H., Bottke, W. F. & Clark, J. P. Mineralogies and source regions of near-Earth asteroids. Didymos Plus in the ultra-low gravity environment it would be easy to generate significant ground motion, potentially triggering an avalanche of rocks. This animation showing a highly magnified view of how Dimorphos orbit around Didymos is seen from Earth, approximately one week after the DART impact. Figure 2 shows range-Doppler images and Extended Data Fig. Didymos and Dimorphos orbit the Sun once every 2.11 years, passing closer to the Earth at some points in the orbit than others. Enlarge Image. Time and Terms of Use. The study is published on the arXiv preprint server. Las Cumbres Observatory Global Telescope network. We assumed the equatorial extents of Didymos and Dimorphos to be 425m and 88m, respectively, and added an angular distance corresponding to 42588=337m (20m (1) uncertainty) in the direction of the limb-to-limb separations to estimate the distances between the COMs. NASA expects the impact to shorten Dimorphos orbit by about 1%. This document is subject to copyright. This document is subject to copyright. Libration-induced orbit period variations following the DART impact. For the 2 October 2022 data, the photometry was measured using the Canopus software package. CNET The NASA Double Asteroid Redirection Test (DART) mission is a planetary defense-driven test of a kinetic impactor on Dimorphos, the satellite of the binary asteroid 65803 Didymos. Dimorphos, which means "having two forms" in Greek, spans 525 feet or 160 meters in diameter. These conclusions are somewhat preliminary, as they are based on best estimates of the asteroid's size, composition, and shape, which the Hera mission should be able to corroborate when it arrives in 2027. Montegriffo, P. et al. While some asteroids fit this classification, just as many do not. Brace for impact: DART successfully slams into asteroid We experimented with summing data spanning a range of time intervals and found that the echo from Dimorphos was not clearly visible in all the data on any given day. ESA - Imagine walking on Heras asteroid - European Space Agency around the Sun. 2) at the 0.010.02-magnitude level. ASI/NASA/APL. The lightcurve analysis method described in ref. The Dimorphos rotational period has not been resolved because of its comparatively small size, the oblate shape of Dimorphos16 and the accuracy of the photometric observations necessary for such a detection. Meyer, A. J. et al. and E.V.R. Dimorphos completes an orbit around Didymos every 11 hours and 55 minutes. The SP22 pre-impact period was 11.9214780.000123(3)h. The SP22 model determines a post-impact period of 11.3720.017(3)h, corresponding to an orbit period change of 33.01.0(3)min. Didymos Didymos is not a danger to our planet. The orbit of the Earth and the orbit of the Didymos-Dimorphos system. Last September NASA's DART mission returned images of the boulder-strewn Dimorphos moonlet just before impacting it, in an audacious and ultimately successful attempt to shift its orbit around its parent asteroid Didymos. Comput. Astron. Li, J.-Y. As a result of the impact, Dimorphos orbit period was shortened and the mean distance from Dimorphos to Didymos was reduced. The couple chosen is the near-Earth asteroid Didymos (in Greek "twin") which has a diameter of 780 m and its satellite Dimorphos (in Greek "which has two shapes") which has a diameter of 163 m and which orbits in synchronous rotation around Didymos in 11 hours and 55 minutes at a distance of 1 180m. Sci. "At around 57 m across, the largest ones are typically house-sized.". Initial measurements of the system post-impact Gaia Data Release 2: summary of the contents and survey properties. B.S. Smaller particles can even escape the system, blown away forever by the solar wind. and T.P. The purpose of the cosmic collision? DART crashed into Dimorphos in a bid to change the moonlet's orbit. Daly, R. T. et al. Some of the floating rocks reach orbit, and some of those are likely to be deposited onto the moon, Dimorphos. Orbital period change of Dimorphos due to the DART kinetic impact, $${F}_{1}\left(t\right)={C}_{1}+\,\mathop{\sum }\limits_{k=1}^{{m}_{1}}\left[{C}_{1k}\cos \frac{2\pi k}{{P}_{1}}\left(t-{t}_{0}\right)+{S}_{1k}\sin \frac{2\pi k}{{P}_{1}}(t-{t}_{0})\right]$$, $$\begin{array}{c}M(t)={M}_{0}+{n}_{0}\left(t-{t}_{0}\right)+\frac{1}{2}\dot{n}{\left(t-{t}_{0}\right)}^{2}\,{\rm{for}}\,t < {t}_{{\rm{imp}}}\\ M(t)={M}_{{\rm{imp}}}+\left({n}_{{\rm{imp}}}+\Delta n\right)\left(t-{t}_{{\rm{imp}}}\right)\,{\rm{for}}\,t > {t}_{{\rm{imp}}}\\ n(t)={n}_{0}+\dot{n}\left(t-{t}_{0}\right)\,{\rm{for}}\,t < {t}_{{\rm{imp}}}\\ n(t)={n}_{{\rm{imp}}}+\Delta n\,{\rm{for}}\,t > {t}_{{\rm{imp}}}\end{array}$$, https://doi.org/10.1038/s41586-023-05805-2. The primary body of the binary system, Didymos, orbits the Sun at a distance of 1.0 to 2.3 AU once every 770 days (2 years and 1 month). Fang, J. Smashing success: NASAs first planetary defense test changes Four observatories contributed data that met the photometric requirements of the lightcurve dataset for the orbital period change (Extended Data Table 2): Las Campanas Observatory 1-m Swope Telescope, the Las Cumbres Observatory Global Telescope (LCOGT) network 1-m telescopes, the Danish 1.54-m telescope at the European Southern Observatorys La Silla site and the Lowell Observatory 1.1-m Hall telescope. 107070K (SPIE, 2018). 5 for estimating the orbital parameters M0, n0, \(\mathop{n}\limits^{. 5 is a less complicated approach compared with the methods presented in ref. Mommert, M. PHOTOMETRYPIPELINE: an automated pipeline for calibrated photometry. The information you enter will appear in your e-mail message and is not retained by Phys.org in any form. 37, 178183 (2006). part may be reproduced without the written permission. Dimorphos, at 160 m across is about the same size as the Great Pyramid of Giza, orbiting around the mountain sized Didymos asteroid, about 780 m across. 65, 12351279 (1993). Provided by Didymos Barbary, K. SEP: Source Extractor as a library. To model the separation of Dimorphos from Didymos in DRACO images, we used SPICE42 to subtract the RA and DEC of the COM of Didymos from those of the COM of Dimorphos as seen from the DART spacecraft. Didymos and Dimorphos are represented by ellipsoids with axial ratios of a1/c1=b1/c1=1.37, a2/c2=1.53 and b2/c2=1.50 (ref. We present 2 min read. If material is not included in the articles Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. We use 1 uncertainties of (T1.5T1)/2 and (T4T3.5)/2 for T1.5 and T3.5, respectively. DART will record images with the Didymos Reconnaissance and Asteroid Camera for Optical navigation. Publ. The Swope 4K CCD is a visible-wavelength, direct-imaging CCD with a 29.729.8arcmin field of view. Swope observations were taken in the Sloan-r filter and used sidereal tracking with one or two sky pointings each night. For general feedback, use the public comments section below (please adhere to guidelines). }\) is the linear drift in mean motion fromnongravitational effects and Mimp and nimp are the mean anomaly and mean motion at impact, respectively. DART was highly successful by all metrics. Apart from any fair dealing for the purpose of private study or research, no

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