How many satellites are orbiting the Earth in 2017?

Satellites orbiting the Earth

Artist’s rendition of satellites orbiting the Earth – rottenman/123RF Stock Photo

If you’d like to see the 2018 update, please click here.

This is our annual update on the satellites currently orbiting the Earth.

How many satellites are orbiting the Earth?
According to the Index of Objects Launched into Outer Space maintained by the United Nations Office for Outer Space Affairs (UNOOSA), there are 4 635 satellites currently orbiting the planet; an increase of 8.91% compared to last year.

So far in 2017, UNOOSA has recorded 357 objects launched into space. This is almost 50% more than have ever previously occurred in a single year, and there are still a significant number planned during the rest of the year.

This increase is fuelled by small satellites and cubesats. New technology has significantly reduced the cost to design, build and launch these, and this has been accompanied with an increase in commercial providers becoming involved in the market. A report issued earlier this month by the Satellite Applications Catapult predicted that 1 300 of these satellites will be launched over the next three years. If you consider that just under 7,900 objects have been launched into space, this would equate to 16.5% of the total launches over the last 60 years!

How many of these orbiting satellites are working?
The Union of Concerned Scientists (UCS) keeps a record of the operational satellites and you may be surprised to know that only 37.5% of the orbiting satellites are active, just 1 738 according to the August 2017 update.

This means that there are 2 897 pieces of junk metal hurtling around the Earth at high speed!

What are all these satellites doing?
According the UCS the main purposes for the operational satellites are:

  • Communications: 742 satellites
  • Earth observation: 596 satellites
  • Technology development/demonstration: 193 satellites
  • Navigation/Positioning: 108 satellites
  • Space science: 66 satellites
  • Earth science: 24 satellites
  • Space observation: 9 satellites

Although, it should be noted that some of the satellites have multiple purposes.We’ll examine the Earth observation category in more detail in a future blog.

What is Technology Development/Demonstration?
This is quite an intriguing purpose as it should give an idea of what is happening in the industry, and perhaps unsurprisingly the UCS data has little information on what these satellites are actually doing. However, some insights can be gained by looking at the operators of, and countries controlling, these satellites.

Looking at the uses for these satellites:

  • 33 have military uses with 80% of these being the USA, the rest from China, Russia and France.
  • 56 have government uses and most of these are operated by National Space Agencies, or associated bodies. China has 52% of these satellites, followed by USA.
  • 65 have Civil uses and these are mostly run by University’s or similar educational establishments.
  • 39 have Commercial uses.

There are 33 different countries operating technology development/demonstration satellites with the USA leading the way having 63, followed by China with 41 and Japan with 19. After this it is mostly just one or two satellites for each country.

Who uses the satellites?
The four categories of users in the previous section can also be reviewed for all satellites, such that:

  • 788 satellites are listed as having commercial uses
  • 461 with government uses
  • 360 with military user; and
  • 129 with civil uses

Although, it should be noted that almost 14% of the satellites are listed as having multiple uses.

Which countries have launched/operate satellites?
According to UNOOSA 70 countries have launched satellites, although this is slightly complicated by the fact that a number of satellites have also been launched by various institutions such as the European Space Agency.

Looking at the UCS database, there are 66 countries listed as currently operating satellites, which means around 25% – 33% of the world’s countries have eyes in space (depending on how you define a country/territory!) There is an interesting infographic on the UCS site showing the change in countries operating satellites between 1966 and 2016.

In terms of countries with the most satellites, the USA significantly leads the way with 803 satellites, almost four times as many as China who is next with 204 and followed by Russia with 142.

Interesting Facts!
Just a few of the interesting things we’ve pulled out of the UCS database:

  • The oldest active satellite is the Amsat-Oscar 7 communications satellite which was launched 43 years ago today! (15th November 1974)
  • Planet operates the largest number of satellites with their constellations accounting for 191 of current active satellites – although with Planet this could have gone up already! Second largest operator is Iridium Communications with 83 satellites.
  • 61.6% of operational satellites are in low-earth orbits (LEO), 30.6% in geostationary orbits, 5.6% in medium-earth orbits and 2.2% in elliptical orbits.
  • Of the LEO, 55.4% are sun-synchronous, 25.6% are non-polar inclined, 15.6% are polar, 1.9% are equatorial, 0.8% are elliptical and 0.1% are cislunar (and yes, we had to look that one up too!) The remainder did not specify an orbit type.

When you look up!
Next time you gaze up into the sky looking at that stars, think about the 4,500 or so hunks of metal twinkling up there too!

17 thoughts on “How many satellites are orbiting the Earth in 2017?

  1. Communications: 742 satellites
    Earth observation: 596 satellites
    Technology development/demonstration: 193 satellites
    Navigation/Positioning: 108 satellites
    Space observation: 66 satellites*
    Earth science: 24 satellites
    Space science: 67 satellites
    Space observation: 9 satellites*
    2 different space observations?

    • Hi,

      Great spot! You are correct, there should not be two space observations. The correct figures should be Space Science: 66 satellites and Space Observations: 9 satellites. The other figure of 67 satellites was an error. The breakdown now adds up to the total described. I’ve updated the blog accordingly. Thanks for letting us know!

  2. Great site for some fantastic information, Thank you. One question though… how far back does your data go? I am searching for a list or a graph that shows the number of active satellites in orbit by year, going back to the first launch. I can’t seem to find this information anywhere.

    • Hi Steve,

      Thanks for your comment. We’ve only been doing our annual snapshot of satellites in orbit since 2014. I don’t know anywhere where you can get the information you are looking for either. The UNOOSA register gives filters which allow you to easily get totals of objects launched per year, but not the active number or number of that came out of orbit for any reasons – although the latter information is in the database, you’d have to go through it line by line to get that. As you can’t download the UNOOSA database, it will be a lot of work.

      It might be worth contacting the Union of Concerned Scientists. They maintain their active satellite database, and although they only show the current version of the website, they obviously have historic versions. I don’t know how far back they might go, but it could be worth a try.

      Sorry we can’t give you any other suggestions! But if you do find somewhere to get this information, please let us know as we’d be interested too!

  3. Hi Andy, thank you for your reply. I will contact the UCS and see if they can help before I try the UNOOSA option.

    Fingers crossed I’ll find what I’m looking for. If I do, I will certainly let you know.


  4. Great information! Satellites are used almost everyday by everyone. Even though you can’t see it, there will probably be one traveling above you today. Satellites are used for many things such as communication, oceanography, astronomy, surveillance, and a variety of other things as well . They help many scientists get a perceptive view at all kinds of objects anywhere in the world.

  5. Can you explain the satellites that seem to “light up” briefly while traveling overhead. The brightness comes on and off and does not seem consistent in duration. It seems to be a cloudless sky, and the object seems bright even while not ‘light up”. When it does “light up” it is very brilliant. Thoughts on what this is?
    Thank you.

    • Hi John,

      We think it’s sunlight being reflected off the solar panels, which varies in brightness due to the changing orientation of the solar arrays and where the Earth’s shadow is. The International Space Station can be very bright because of its much larger solar arrays.

  6. How come none of the 3000 shiny tinboxes populating the LEO never get filmed by the 24/7 streaming camera of the iss?

    • That’s an excellent question, and to be honest, we’re not 100% sure of the answer.
      Our thoughts are that the ISS itself is in a fairly LEO compared to other LEO satellites, and obviously as all the satellites at this height will be orbiting at the same speed the ISS will never pass over any other satellite for it to be seen.
      There are probably a number of cubesats that are below the ISS height, but the problem is that would pass quickly through the cameras field of view and so could be difficult to see.
      These are our thoughts, but has anyone else got a better answer?

  7. I am glad to gain this remarkable information from you.
    I have found here lots of interesting information for my knowledge I need.
    All the details you provide to us, it was very helpful and useful.
    Thanks for sharing this amazing post.

    • Thanks for the question. According to the United Nations Office of Outer Space Affairs, there were 5,062 satellites orbiting the Earth as at the 13th March 2019.

      Although, you should note that the precise number changes frequently as new satellites are launched, and older satellites are deorbited.

      Hope this helps.

  8. hello,
    Found your post interesting to read. I cant wait to see your post soon. Good Luck for the upcoming update.This article is really very interesting and effective.

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