31cm WorldView-3 Sends First Crisp Images

As we said in a last year’s post and another post about WorldView-3 replacing the GeoEye-2 sensor in launch priority, the new sensor is all about breaking new ground.  The current WorldView-3 sensor launched on August 31st, 2014, is a massive technological achievement as evident from following sample images released by DigitalGlobe. Please note that these images were acquired at 30 cm GSD but had to to be resampled to 40cm due to legal restriction. Customer can enjoy the details of full 30cm resolution after 21 Feb, 2015(note at the end of the post gives more clarification).

So, let us have a look at pre-calibration imagery released by DigitalGlobe:

40 cm resolution images from WorldView-3 Sensor. Courtesy: DigitalGlobe

Below is how imagery looks at optimum 40cm resolution:

WorldView-2 sensor imagery showing stunning details even though it is 40cm image. 30 cm images will be available from February 2015.
Image Courtesy: DigitalGlobe

You can also browse the large scene of the Madrid imagery below. 

We recommend using the following browsers: Chrome, Firefox or Safari.

 

As shown in our WorldView-3 samples, customers can more easily determine the type of vehicle (cars, trucks, sedans, mini vans) and its speed and direction, which is valuable for a range of industry vertical customers. With 30 cm super-spectral imagery, quantitative assessments of the state of highway networks — including surface wear — can provide valuable maintenance planning information to national, state, and local governments.

 Below is a recap of sensor specifications:

Panchromatic	Panchromatic: 450 – 800 nm
Multispectral (8 Bands)	Coastal : 400 – 450 nm Blue : 450 – 510 nm Green : 510 – 580 nm Yellow : 585 – 625 nm Red : 630 – 690 nm Red Edge : 705 – 745 nm Near-IR1 : 770 – 895 nm Near-IR2 : 860 – 1040 nm
SWIR Bands (8 Bands)	SWIR-1 : 1195 – 1225 nm SWIR-2 : 1550 – 1590 nm SWIR-3 : 1640 – 1680 nm SWIR-4 : 1710 – 1750 nm SWIR-5 : 2145 – 2185 nm SWIR-6 : 2185 – 2225 nm SWIR-7 : 2235 – 2285 nm SWIR-8 : 2295 – 2365 nm
CAVIS* Bands(12 Bands) *Clouds, Aerosol, Vapor, Ice, Snow	Desert Clouds : 405 – 420 nm Aerosol-1 : 459 – 509 nm Green : 525 – 585 nm Aerosol-2 : 620 – 670 nm Water-1 : 845 – 885 nm Water-2 : 897 – 927 nm Water-3 : 930 – 965 nm NDVI-SWIR : 1220 – 1252 nm Cirrus : 1350 – 1410 nm Snow : 2105 – 2245 nm Aerosol-3 : 1620 – 1680 nm Aerosol-3 : 2105 – 2245 nm

 

WorldView-3 has following other Design and Specification features. Particularly interesting are highest Pan resolution of 0.31m, 30m CAVIS bands and a locational accuracy of 3.5m CE90 comparable to the GeoEye-1

 

Orbit	Altitude: 617 km Type: SunSync, 1:30 pm descending Node Period: 97 min.
Life	Spec Mission Life: 7.25 years Estimated Service Life: 10 to 12 years
Sensor Resolution (or GSD, Ground Sample Distance; off-nadir is geometric mean)	Pan Nadir: 0.31 m(20° Off-Nadir: 0.34 m) Multispectral Nadir: 1.24 m(20° Off-Nadir: 1.38 m) SWIR Nadir: 3.70 m(20° Off-Nadir: 4.10 m) CAVIS Nadir: 30.00 m
Dynamic Range	11-bits per pixel Pan and MS 14-bits per pixel SWIR
Swath Width	At nadir: 13.1 km
Attitude Determination and Control	Type: 3-axis Stabilized Actuators: Control Moment Gyros (CMGs) Sensors: Star trackers, precision IRU, GPS
Pointing Accuracy and Knowledge	Accuracy: <500 m at image start/stop Knowledge: Supports geolocation accuracy given below
Retargeting Agility	Time to Slew 200 km: 12 sec
Max Contiguous Area Collected in a Single Pass (30° off-nadir angle)	Mono: 66.5 km x 112 km (5 strips) Stereo: 26.6 km x 112 km (2 pairs)
Revisit Frequency (at 40°N Latitude)	1 m GSD: <1.0 day 4.5 days at 20° off-nadir or less
Geolocation Accuracy (CE90)	Predicted <3.5 m CE90 without ground control
Capacity	680,000 km2 per day

Above specifications notwithstanding, following is an important note fro DigitalGobe:

“Note: DigitalGlobe formally notified the U.S. National Oceanic and Atmospheric Administration (NOAA) of WorldView-3’s IOC, which means that beginning on February 21, 2015, we will able to deliver 30 cm imagery to all of our customers. In the meantime, we will make 40 cm panchromatic and 1.6 m multispectral data available to our customers when WorldView-3 completes its validation and testing. Data from the satellite’s new shortwave infrared (SWIR) sensor will also be available to customers, however the resolution of this data will be restricted to 7.5 m while NOAA is conducting a six-month study of the capability.”

This post will be continued…