{
    "id": 12754,
    "url": "https://svs.gsfc.nasa.gov/12754/",
    "page_type": "Produced Video",
    "title": "Landsat sensors: pushbroom vs whiskbroom",
    "description": "Landsat collects images in long narrow strips called “swaths.” Each swath is 185 kilometers (115 miles) wide and is 2,752 kilometers (1,710 miles) from the next adjacent swath taken that day. It takes 16 days for the swaths to overlap enough to image the whole Earth.Previous Landsat sensors swept back and forth across the swath like a whisk broom to collect data. The sensor looked at a calibration source at the end of every row, which means that measurements were consistent from orbit to orbit. But this sensor design requires fast-moving parts, which are more likely to break.—and which did on Landsat 7.In contrast, the instruments on Landsat 8 view across the entire swath at once, building strips of data like a pushbroom. This approach requires no moving parts and gives the sensor detectors greater dwell time. The pushbroom instrument is smaller and lighter than previous whisk broom instruments, but its calibration is much more complex given the large number of detectors.“It was a natural step to evolve to a pushbroom sensor. The technology was proven on other satellites, and we knew we could get better accuracy. The pushbroom has no moving parts. It is a newer and more reliable technology.” explains Terry Arvidson, senior project engineer.For more information on the future of Landsat instruments, read https://landsat.gsfc.nasa.gov/landsat-9/instruments/. || ",
    "release_date": "2017-10-31T00:00:00-04:00",
    "update_date": "2023-05-03T13:47:15.499665-04:00",
    "main_image": {
        "id": 410035,
        "url": "https://svs.gsfc.nasa.gov/vis/a010000/a012700/a012754/pushbroomTIFF_00620_print.jpg",
        "filename": "pushbroomTIFF_00620_print.jpg",
        "media_type": "Image",
        "alt_text": "The instruments on Landsat 8 have linear detector arrays, also called \"pushbroom\" detectors, which collect data across the entire image swath at once. ",
        "width": 1024,
        "height": 576,
        "pixels": 589824
    },
    "main_video": {
        "id": 410030,
        "url": "https://svs.gsfc.nasa.gov/vis/a010000/a012700/a012754/Landsat_8_pushbroom_sensor-prores.mov",
        "filename": "Landsat_8_pushbroom_sensor-prores.mov",
        "media_type": "Movie",
        "alt_text": "The instruments on Landsat 8 have linear detector arrays, also called \"pushbroom\" detectors, which collect data across the entire image swath at once. ",
        "width": 1920,
        "height": 1080,
        "pixels": 2073600
    },
    "main_credits": {
        "Produced by": [
            {
                "name": "Matthew R. Radcliff",
                "employer": "USRA"
            }
        ]
    },
    "progress": "Complete",
    "media_groups": [
        {
            "id": 328704,
            "url": "https://svs.gsfc.nasa.gov/12754/#media_group_328704",
            "widget": "Basic text with HTML",
            "title": "",
            "caption": "",
            "description": "Landsat collects images in long narrow strips called “swaths.” Each swath is 185 kilometers (115 miles) wide and is 2,752 kilometers (1,710 miles) from the next adjacent swath taken that day. It takes 16 days for the swaths to overlap enough to image the whole Earth.<br><br>Previous Landsat sensors swept back and forth across the swath like a whisk broom to collect data. The sensor looked at a calibration source at the end of every row, which means that measurements were consistent from orbit to orbit. But this sensor design requires fast-moving parts, which are more likely to break.—<a href=\"http://landsat.usgs.gov/products_slcoffbackground.php\">and which did on Landsat 7</a>.<br><br>In contrast, the instruments on Landsat 8 view across the entire swath at once, building strips of data like a pushbroom. This approach requires no moving parts and gives the sensor detectors greater dwell time. The pushbroom instrument is smaller and lighter than previous whisk broom instruments, but its calibration is much more complex given the large number of detectors.<br><br>“It was a natural step to evolve to a pushbroom sensor. The technology was proven on other satellites, and we knew we could get better accuracy. The pushbroom has no moving parts. It is a newer and more reliable technology.” explains Terry Arvidson, senior project engineer.<br><br>For more information on the future of Landsat instruments, read <a href=\"https://landsat.gsfc.nasa.gov/landsat-9/instruments/\">https://landsat.gsfc.nasa.gov/landsat-9/instruments/</a>.",
            "items": [],
            "extra_data": {}
        },
        {
            "id": 328705,
            "url": "https://svs.gsfc.nasa.gov/12754/#media_group_328705",
            "widget": "Video player",
            "title": "",
            "caption": "",
            "description": "The instruments on Landsat 8 have linear detector arrays, also called \"pushbroom\" detectors, which collect data across the entire image swath at once. ",
            "items": [
                {
                    "id": 254312,
                    "type": "media",
                    "extra_data": null,
                    "title": null,
                    "caption": null,
                    "instance": {
                        "id": 410035,
                        "url": "https://svs.gsfc.nasa.gov/vis/a010000/a012700/a012754/pushbroomTIFF_00620_print.jpg",
                        "filename": "pushbroomTIFF_00620_print.jpg",
                        "media_type": "Image",
                        "alt_text": "The instruments on Landsat 8 have linear detector arrays, also called \"pushbroom\" detectors, which collect data across the entire image swath at once. ",
                        "width": 1024,
                        "height": 576,
                        "pixels": 589824
                    }
                },
                {
                    "id": 254313,
                    "type": "media",
                    "extra_data": null,
                    "title": null,
                    "caption": null,
                    "instance": {
                        "id": 410036,
                        "url": "https://svs.gsfc.nasa.gov/vis/a010000/a012700/a012754/pushbroomTIFF_00620_searchweb.png",
                        "filename": "pushbroomTIFF_00620_searchweb.png",
                        "media_type": "Image",
                        "alt_text": "The instruments on Landsat 8 have linear detector arrays, also called \"pushbroom\" detectors, which collect data across the entire image swath at once. ",
                        "width": 320,
                        "height": 180,
                        "pixels": 57600
                    }
                },
                {
                    "id": 254314,
                    "type": "media",
                    "extra_data": null,
                    "title": null,
                    "caption": null,
                    "instance": {
                        "id": 410037,
                        "url": "https://svs.gsfc.nasa.gov/vis/a010000/a012700/a012754/pushbroomTIFF_00620_thm.png",
                        "filename": "pushbroomTIFF_00620_thm.png",
                        "media_type": "Image",
                        "alt_text": "The instruments on Landsat 8 have linear detector arrays, also called \"pushbroom\" detectors, which collect data across the entire image swath at once. ",
                        "width": 80,
                        "height": 40,
                        "pixels": 3200
                    }
                },
                {
                    "id": 254307,
                    "type": "media",
                    "extra_data": null,
                    "title": null,
                    "caption": null,
                    "instance": {
                        "id": 410030,
                        "url": "https://svs.gsfc.nasa.gov/vis/a010000/a012700/a012754/Landsat_8_pushbroom_sensor-prores.mov",
                        "filename": "Landsat_8_pushbroom_sensor-prores.mov",
                        "media_type": "Movie",
                        "alt_text": "The instruments on Landsat 8 have linear detector arrays, also called \"pushbroom\" detectors, which collect data across the entire image swath at once. ",
                        "width": 1920,
                        "height": 1080,
                        "pixels": 2073600
                    }
                },
                {
                    "id": 254308,
                    "type": "media",
                    "extra_data": null,
                    "title": null,
                    "caption": null,
                    "instance": {
                        "id": 410031,
                        "url": "https://svs.gsfc.nasa.gov/vis/a010000/a012700/a012754/Landsat_8_pushbroom_sensor_large.mp4",
                        "filename": "Landsat_8_pushbroom_sensor_large.mp4",
                        "media_type": "Movie",
                        "alt_text": "The instruments on Landsat 8 have linear detector arrays, also called \"pushbroom\" detectors, which collect data across the entire image swath at once. ",
                        "width": 1920,
                        "height": 1080,
                        "pixels": 2073600
                    }
                },
                {
                    "id": 254309,
                    "type": "media",
                    "extra_data": null,
                    "title": null,
                    "caption": null,
                    "instance": {
                        "id": 410032,
                        "url": "https://svs.gsfc.nasa.gov/vis/a010000/a012700/a012754/Landsat_8_pushbroom_sensor.webm",
                        "filename": "Landsat_8_pushbroom_sensor.webm",
                        "media_type": "Movie",
                        "alt_text": "The instruments on Landsat 8 have linear detector arrays, also called \"pushbroom\" detectors, which collect data across the entire image swath at once. ",
                        "width": 960,
                        "height": 540,
                        "pixels": 518400
                    }
                },
                {
                    "id": 254310,
                    "type": "media",
                    "extra_data": null,
                    "title": null,
                    "caption": null,
                    "instance": {
                        "id": 410033,
                        "url": "https://svs.gsfc.nasa.gov/vis/a010000/a012700/a012754/frames/1920x1080_16x9_30p/pushbroomTIFF/",
                        "filename": "pushbroomTIFF",
                        "media_type": "Frames",
                        "alt_text": "The instruments on Landsat 8 have linear detector arrays, also called \"pushbroom\" detectors, which collect data across the entire image swath at once. ",
                        "width": 1920,
                        "height": 1080,
                        "pixels": 2073600
                    }
                },
                {
                    "id": 254311,
                    "type": "media",
                    "extra_data": null,
                    "title": null,
                    "caption": null,
                    "instance": {
                        "id": 410034,
                        "url": "https://svs.gsfc.nasa.gov/vis/a010000/a012700/a012754/pushbroomTIFF_00620.tif",
                        "filename": "pushbroomTIFF_00620.tif",
                        "media_type": "Image",
                        "alt_text": "The instruments on Landsat 8 have linear detector arrays, also called \"pushbroom\" detectors, which collect data across the entire image swath at once. ",
                        "width": 1920,
                        "height": 1080,
                        "pixels": 2073600
                    }
                },
                {
                    "id": 254315,
                    "type": "media",
                    "extra_data": null,
                    "title": null,
                    "caption": null,
                    "instance": {
                        "id": 851469,
                        "url": "https://svs.gsfc.nasa.gov/vis/a010000/a012700/a012754/GSFC_20171031_Landsat_m12754_pushbroom.en_US.vtt",
                        "filename": "GSFC_20171031_Landsat_m12754_pushbroom.en_US.vtt",
                        "media_type": "Captions",
                        "alt_text": "The instruments on Landsat 8 have linear detector arrays, also called \"pushbroom\" detectors, which collect data across the entire image swath at once. ",
                        "label": "English",
                        "language_code": ""
                    }
                }
            ],
            "extra_data": {}
        },
        {
            "id": 328706,
            "url": "https://svs.gsfc.nasa.gov/12754/#media_group_328706",
            "widget": "Video player",
            "title": "",
            "caption": "",
            "description": "Landsat 7, and previous Landsat satellites, had detectors that swept back-and-forth, like a whisk broom, as they collected data across the image swath.",
            "items": [
                {
                    "id": 254321,
                    "type": "media",
                    "extra_data": null,
                    "title": null,
                    "caption": null,
                    "instance": {
                        "id": 410043,
                        "url": "https://svs.gsfc.nasa.gov/vis/a010000/a012700/a012754/whiskbroomTIFF_00625_print.jpg",
                        "filename": "whiskbroomTIFF_00625_print.jpg",
                        "media_type": "Image",
                        "alt_text": "Landsat 7, and previous Landsat satellites, had detectors that swept back-and-forth, like a whisk broom, as they collected data across the image swath.",
                        "width": 1024,
                        "height": 576,
                        "pixels": 589824
                    }
                },
                {
                    "id": 254316,
                    "type": "media",
                    "extra_data": null,
                    "title": null,
                    "caption": null,
                    "instance": {
                        "id": 410039,
                        "url": "https://svs.gsfc.nasa.gov/vis/a010000/a012700/a012754/Landsat_7_whiskbroom_sensor-prores.mov",
                        "filename": "Landsat_7_whiskbroom_sensor-prores.mov",
                        "media_type": "Movie",
                        "alt_text": "Landsat 7, and previous Landsat satellites, had detectors that swept back-and-forth, like a whisk broom, as they collected data across the image swath.",
                        "width": 1920,
                        "height": 1080,
                        "pixels": 2073600
                    }
                },
                {
                    "id": 254317,
                    "type": "media",
                    "extra_data": null,
                    "title": null,
                    "caption": null,
                    "instance": {
                        "id": 410040,
                        "url": "https://svs.gsfc.nasa.gov/vis/a010000/a012700/a012754/Landsat_7_whiskbroom_sensor_large.mp4",
                        "filename": "Landsat_7_whiskbroom_sensor_large.mp4",
                        "media_type": "Movie",
                        "alt_text": "Landsat 7, and previous Landsat satellites, had detectors that swept back-and-forth, like a whisk broom, as they collected data across the image swath.",
                        "width": 1920,
                        "height": 1080,
                        "pixels": 2073600
                    }
                },
                {
                    "id": 254318,
                    "type": "media",
                    "extra_data": null,
                    "title": null,
                    "caption": null,
                    "instance": {
                        "id": 410041,
                        "url": "https://svs.gsfc.nasa.gov/vis/a010000/a012700/a012754/Landsat_7_whiskbroom_sensor.webm",
                        "filename": "Landsat_7_whiskbroom_sensor.webm",
                        "media_type": "Movie",
                        "alt_text": "Landsat 7, and previous Landsat satellites, had detectors that swept back-and-forth, like a whisk broom, as they collected data across the image swath.",
                        "width": 960,
                        "height": 540,
                        "pixels": 518400
                    }
                },
                {
                    "id": 254319,
                    "type": "media",
                    "extra_data": null,
                    "title": null,
                    "caption": null,
                    "instance": {
                        "id": 410038,
                        "url": "https://svs.gsfc.nasa.gov/vis/a010000/a012700/a012754/frames/1920x1080_16x9_30p/whiskbroomTIFF/",
                        "filename": "whiskbroomTIFF",
                        "media_type": "Frames",
                        "alt_text": "Landsat 7, and previous Landsat satellites, had detectors that swept back-and-forth, like a whisk broom, as they collected data across the image swath.",
                        "width": 1920,
                        "height": 1080,
                        "pixels": 2073600
                    }
                },
                {
                    "id": 254320,
                    "type": "media",
                    "extra_data": null,
                    "title": null,
                    "caption": null,
                    "instance": {
                        "id": 410042,
                        "url": "https://svs.gsfc.nasa.gov/vis/a010000/a012700/a012754/whiskbroomTIFF_00625.tif",
                        "filename": "whiskbroomTIFF_00625.tif",
                        "media_type": "Image",
                        "alt_text": "Landsat 7, and previous Landsat satellites, had detectors that swept back-and-forth, like a whisk broom, as they collected data across the image swath.",
                        "width": 1920,
                        "height": 1080,
                        "pixels": 2073600
                    }
                },
                {
                    "id": 254322,
                    "type": "media",
                    "extra_data": null,
                    "title": null,
                    "caption": null,
                    "instance": {
                        "id": 851470,
                        "url": "https://svs.gsfc.nasa.gov/vis/a010000/a012700/a012754/GSFC_20171031_Landsat_m12754_whiskbroom.en_US.vtt",
                        "filename": "GSFC_20171031_Landsat_m12754_whiskbroom.en_US.vtt",
                        "media_type": "Captions",
                        "alt_text": "Landsat 7, and previous Landsat satellites, had detectors that swept back-and-forth, like a whisk broom, as they collected data across the image swath.",
                        "label": "English",
                        "language_code": ""
                    }
                }
            ],
            "extra_data": {}
        }
    ],
    "studio": "gms",
    "funding_sources": [
        "PAO"
    ],
    "credits": [
        {
            "role": "Producer",
            "people": [
                {
                    "name": "Matthew R. Radcliff",
                    "employer": "USRA"
                }
            ]
        },
        {
            "role": "Technical support",
            "people": [
                {
                    "name": "Aaron E. Lepsch",
                    "employer": "ADNET Systems, Inc."
                }
            ]
        },
        {
            "role": "Scientist",
            "people": [
                {
                    "name": "James R. Irons",
                    "employer": "NASA/GSFC"
                }
            ]
        },
        {
            "role": "Animator",
            "people": [
                {
                    "name": "Tyler Chase",
                    "employer": "USRA"
                }
            ]
        }
    ],
    "missions": [
        "Landsat",
        "LDCM: Landsat Data Continuity Mission"
    ],
    "series": [
        "Landsat",
        "Landsat 7",
        "LDCM"
    ],
    "tapes": [],
    "papers": [],
    "datasets": [],
    "nasa_science_categories": [
        "Earth"
    ],
    "keywords": [
        "Engineering",
        "Landsat",
        "Orbit",
        "Satellite",
        "Spacecraft",
        "Swath",
        "Technology"
    ],
    "recommended_pages": [],
    "related": [
        {
            "id": 13259,
            "url": "https://svs.gsfc.nasa.gov/13259/",
            "page_type": "Produced Video",
            "title": "Landsat 9 Spacecraft Animations and Stills",
            "description": "Landsat 9 is a collaboration between NASA and the U.S. Geological Survey, and will continue the Landsat program’s critical role in monitoring, understanding and managing the land resources needed to sustain human life. The mission will provide moderate-resolution (15 meter to 100 meter, depending on spectral frequency) measurements of the Earth's terrestrial and polar regions in visible, near-infrared, short wave infrared, and thermal infrared wavelengths. There are two instruments on the spacecraft, the Thermal InfraRed Sensor 2 (TIRS-2) and the Operational Land Imager 2 (OLI-2).Landsat 9 will provide continuity with the nearly 50-year long Landsat land imaging data set. In addition to widespread routine use for land use planning and monitoring on regional to local scales, support of disaster response and evaluations, and water use monitoring, Landsat measurements directly serve NASA research in the focus areas of climate, carbon cycle, ecosystems, water cycle, biogeochemistry, and Earth surface/interior.The Landsat program is the only U.S. satellite system designed and operated to repeatedly observe the global land surface at a moderate scale that shows both natural and human-induced change. || ",
            "release_date": "2019-07-26T00:00:00-04:00",
            "update_date": "2024-06-23T23:22:51.648131-04:00",
            "main_image": {
                "id": 394538,
                "url": "https://svs.gsfc.nasa.gov/vis/a010000/a013200/a013259/Landsat9_still_SW2_print.jpg",
                "filename": "Landsat9_still_SW2_print.jpg",
                "media_type": "Image",
                "alt_text": "An artist's conception of the Landsat 9 spacecraft, the ninth satellite launched in the long-running Landsat program, high above the Western US.",
                "width": 1024,
                "height": 576,
                "pixels": 589824
            }
        },
        {
            "id": 11491,
            "url": "https://svs.gsfc.nasa.gov/11491/",
            "page_type": "Produced Video",
            "title": "Landsat 8 Onion Skin",
            "description": "Landsat satellites circle the globe every 99 minutes, collecting data about the land surfaces passing underneath.  After 16 days, the Landsat satellite has passed over every spot on the globe, and recorded data in 11 different wavelength regions.  The individual wavelength bands can be combined into color images, with different combinations of the 11 bands revealing different information about the condition of the land cover.The data for this video was collected by Landsat 5 on November 10, 2011. || ",
            "release_date": "2014-02-24T19:00:00-05:00",
            "update_date": "2023-05-03T13:51:09.742322-04:00",
            "main_image": {
                "id": 458057,
                "url": "https://svs.gsfc.nasa.gov/vis/a010000/a011400/a011491/G2014-020_Onion_Skin_MASTER_nasaportal_print.jpg",
                "filename": "G2014-020_Onion_Skin_MASTER_nasaportal_print.jpg",
                "media_type": "Image",
                "alt_text": "Landsat satellites circle the globe, recording data in 11 different wavelengths.  The individual wavelength bands can be combined into color images, with different combinations of the 11 bands revealing different information about the condition of the land cover.For complete transcript, click here.Watch this video on the NASA Goddard YouTube channel.This video is also available on our YouTube channel.",
                "width": 1024,
                "height": 576,
                "pixels": 589824
            }
        },
        {
            "id": 11481,
            "url": "https://svs.gsfc.nasa.gov/11481/",
            "page_type": "Produced Video",
            "title": "Landsat Orbit Swath",
            "description": "This visualization of the orbit of Landsat 8 is narrated by Jim Irons, LDCM Project Scientist at NASA's Goddard Space Flight Center.As a Landsat satellite flies over the surface of the Earth the instruments aboard the satellite are able to view a swath 185 kilometers wide and collect images along that swath as the satellite proceeds through its orbit. The spacecraft travels at approximately 4.7 miles per second. The satellite travels from north to south while it's over the sunlit portion of the Earth, and travels south to north over the dark side of the Earth. One orbit takes about 99 minutes, so that's about approximately 15 orbits in a 24 hour period. The orbit's maintained such that after 16 days, the entire surface of the Earth has come within view of the Landsat instruments, while sunlit, and then on day 17 the first ground path is repeated. So we get to view the entire surface once every 16 days. || ",
            "release_date": "2014-02-11T10:00:00-05:00",
            "update_date": "2023-05-03T13:51:14.032859-04:00",
            "main_image": {
                "id": 458276,
                "url": "https://svs.gsfc.nasa.gov/vis/a010000/a011400/a011481/G2014-016_LDCM_orbit_swath.png",
                "filename": "G2014-016_LDCM_orbit_swath.png",
                "media_type": "Image",
                "alt_text": "As a Landsat satellite flies over the surface of the Earth the instruments aboard the satellite are able to view a swath 185 kilometers wide and collect images along that swath as the satellite proceeds through its orbit. The spacecraft travels at approximately 4.7 miles per second. The satellite travels from north to south while it's over the sunlit portion of the Earth, and travels south to north over the dark side of the Earth. One orbit takes about 99 minutes, so that's about approximately 15 orbits in a 24 hour period. The orbit's maintained such that after 16 days, the entire surface of the Earth has come within view of the Landsat instruments, while sunlit, and then on day 17 the first ground path is repeated. So we get to view the entire surface once every 16 days.For complete transcript, click here.Watch this video on the NASA Goddard YouTube channel.",
                "width": 1280,
                "height": 720,
                "pixels": 921600
            }
        }
    ],
    "sources": [],
    "products": [
        {
            "id": 11166,
            "url": "https://svs.gsfc.nasa.gov/11166/",
            "page_type": "Produced Video",
            "title": "Landsat 8 Overview",
            "description": "The Landsat Data Continuity Mission (LDCM) is a collaboration between NASA and the U.S. Geological Survey that will continue the Landsat Program's 40-year data record of monitoring Earth's landscapes from space. LDCM will expand and improve on that record with observations that advance a wide range of Earth sciences and contribute to the management of agriculture, water and forest resources.The Landsat Program is a series of Earth-observing satellite missions jointly managed by NASA and the U.S. Geological Survey. The first Landsat satellite launched in 1972 and the next satellite in the series, the Landsat Data Continuity Mission — LDCM, is scheduled to launch on February 11, 2013 || ",
            "release_date": "2013-01-10T10:00:00-05:00",
            "update_date": "2023-05-03T13:52:29.532886-04:00",
            "main_image": {
                "id": 469173,
                "url": "https://svs.gsfc.nasa.gov/vis/a010000/a011100/a011166/Screen_Shot_2013-01-10_at_10.14.41_AM.png",
                "filename": "Screen_Shot_2013-01-10_at_10.14.41_AM.png",
                "media_type": "Image",
                "alt_text": "The Landsat Data Continuity Mission (LDCM) is a collaboration between NASA and the U.S. Geological Survey that will continue the Landsat Program's 40-year data record of monitoring Earth's landscapes from space. LDCM will expand and improve on that record with observations that advance a wide range of Earth sciences and contribute to the management of agriculture, water and forest resources.For complete transcript, click here.",
                "width": 1239,
                "height": 691,
                "pixels": 856149
            }
        }
    ],
    "newer_versions": [],
    "older_versions": [],
    "alternate_versions": []
}