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Record satellite launch allows Planet to image the planet daily

A record breaking launch by India, on February 15th, 2017, put 104 satellites into orbit, including some 88 ‘Dove’ satellites owned by satellite imaging company Planet. The previous record for ‘most satellites launched in one go’ was 39 satellites and was held by Russia. Read more about the launch here.


PSLV-C37 at launch. Image credit: Indian Space Research Organisation (ISRO)

Planet already had a large number of Doves in orbit, but this launch more than doubled their fleet. Planet has now achieved its goal of being able to image all of earth’s landmass every day. The Doves have a resolution of 3-5m per pixel. Planet also owns the five Rapid Eye satellites, which have a resolution of around 5m per pixel. In addition, Planet is in the process of acquiring Terra Bella from Google, which comes with 7 sub-metre resolution satellites, and plans to launch many more.

Exactly how many Doves Planet has is a little unclear. Their previous blog post on the Terra Bella purchase, stated that they had a fleet of 60 medium resolution satellites. The blog post for this launch of 88 satellites states the new total is 144. Then later on in the same post, they say the entire fleet totals 149 satellites. We assume this is including the 5 Rapid Eye satellites, but not Terra Bella’s. So maybe 4 satellites were deorbited recently?

Sale of Terra Bella to Planet now official

Last month we reported on a rumour that Google’s parent company, Alphabet, was selling their satellite imaging company Terra Bella to another satellite imaging company Planet. It is now official as announced on both the Planet Blog and Terra Bella’s home page (which directs you to the Planet Blog article). Terra Bella was formerly SkyBox Imaging and was acquired by Google in 2014.

The announcement says that the deal includes a multi-year contract between Planet and Google whereby Google will purchase Earth-imaging data from Planet. What we don’t know is what Google plans to do with the imagery. Do any of our readers know? We have not seen much in the way of Terra Bella imagery in Google Earth. We have seen some imagery from them in cases of disaster response. We assume Terra Bella has a number of corporate customers, but presumably those will stay with Terra Bella – becoming Planet customers.

Google Earth would actually benefit from Terra Bella imagery in areas where it doesn’t yet have high resolution imagery – which is actually quite a lot of places, typically hard to photograph areas such as the far north or tropical rain forests with near permanent cloud cover. Another opportunity would be more global mosaics, but this time using higher resolution Planet imagery rather than the relatively low resolution Landsat / Sentinel-2 imagery.

Over the last few years, Planet has become the world leader in medium resolution, high frequency satellite imagery. They have 60 medium resolution satellites (3-5m per pixel). That is set to more than double this Valentine’s Day when they plan to launch another 88 all at once. They also own the Rapid Eye satellites (five satellites with approx. 5m per pixel resolution) which they acquired in 2015. Terra Bella has 7 sub-metre resolution satellites and plans to launch many more. In contrast, the other major players in the Satellite imaging business have fewer satellites but higher resolution (down to 25cm per pixel in some cases).

Planet imagery for natural disaster response

Satellite imaging company Planet has a programme for gathering satellite imagery for natural disaster response. Read more about it on the Planet blog. Although direct and timely access to the imagery for first responders requires emailing Planet and getting special access, there is actually quite a lot of imagery publicly available on the ‘disaster data’ page. It includes a list of recent disasters and some associated imagery and in many cases the option to download sets of imagery for the affected areas.


Pamplona, Cagayan Region, Philippines. Before and after Typhoon Haima. Image credit Planet.

Planet’s imagery is medium resolution in the 3-5 metre range, higher resolution than Landsat and Sentinel-2 but lower resolution than DigitalGlobe and CNES / Astrium. For a list of satellites and resolutions see here.

DigitalGlobe has a similar programme called ‘FirstLook’ whose imagery often makes it into Google Earth and much of the imagery we look at on this blog comes from that programme.