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What is the biggest, by the means of satellite amount, satellite constellation in space right now?

uhoh
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VolkanOzcan
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    Please think out the question's clarity: "by satellite amount" ... what do you mean, of mass, or numbers of very small items? The total "constellation" mass of flock3p is less than 500kg. The mass of a single Iridium 1st generation satellite > 600kg which is greater than the whole total flock 3p mass. Then multiply by 98 launched, most still in orbit. Or... constellation of the ISS, 1 off, but amount (i.e. mass) > 400 tonnes. – Puffin Mar 23 '17 at 00:11
  • ...then there's Project West Ford, where the constellation size is hard to determine but may still count in tens of thousands. – SF. Aug 15 '21 at 10:10

2 Answers2

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Since 'right now' applies whenever this question is read,) even four years after the question was asked, the answer has to be Starlink, which has 1700 satellites deployed in its constellation. Authorization is for 4408 Ku and Ka band (12-18, 26-40ghz) satellites.

Update:

Just read an FCC filing that Starlink Gen2 plan is for 30,000 satellites operating in very low 320-270km orbits, each with 3x the data bandwidth (eband 60-90ghz) of the Gen1 satellites which are at ~550km.

Double Update:

Just read an article "Rwanda submits ITU filing for constellation of 327,320 satellites – 27 orbital shells at 550-640 km". Don't have ITU access so could not verify, but if anybody else can I'd like to know. Rwanda "launched" its first satellite in 2019, one of three cubesats carried on a JAXA supply mission to the ISS.

Pilothead
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    This is the right answer and is probably going to continue to be the right answer for quite a while! – uhoh Aug 15 '21 at 06:30
  • Also the biggest waste of orbital resource, for a while. If it is not sustainable financially, fortunately these satellites will fall back in a short while (being at 550Km). Already about 60 have fallen back. – Ng Ph Aug 15 '21 at 08:09
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    @uhoh Your comment about the future made me curious as to Starlink plans, so I looked into it and updated my answer. – Pilothead Aug 16 '21 at 17:57
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    @NgPh as someone with very bad rural internet service with no improvement on the horizon, it doesn't seem like the "biggest waste" to me. Genuine question: are the Starlink constellations interfering or impeding other operators? Are there other operators who would like to occupy these orbits, but can't? – f_n_lyre Aug 16 '21 at 18:15
  • @f-n-lyre, point taken. Likewise, somebody living in the Sahara, and rich enough, wouldn't find it extravagant to have a swimming pool in his backyard. As well, somebody in Saudi Arabia would find it normal to have an alpine ski resort there. But let's step back a bit. How many of you in rural areas really need 100+ Mbps Internet? Is your life so miserable w/o fast online gaming? The issue I alluded to is the increase of debris that Musk & Co are putting out there for your comfort in rural areas, which "out there" can be used better for mankind than broadband service everywhere. – Ng Ph Aug 16 '21 at 20:03
  • @Pilotahead, do you consider the authors of this paper part of the "fews" making up the issue of debris? In my opinion, 10mbps is a decent speed for broadband service. Ultra-broadband everywhere is a fabricated demand of the well-off fews. – Ng Ph Aug 16 '21 at 21:38
  • @NgPh Stack Exchange works best in the question post and answer post format which provide space to develop clear explorations and arguments of topics and for community feedback, whereas discussions in comments can sometimes spiral and diverge and often just get cleaned up by the moderators since it's not what comments are for. So to provide space for this interesting topic I've just asked How much could a full-blown Starlink constellation contribute to a future Kessler scenario? What would be the worst-case scenario? – uhoh Aug 17 '21 at 00:17
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Planet Labs' Flock 3p, a constellation of 88 Dove satellites, was recently launched aboard ISRO's PSLV-C37, the record-breaking launch of 104 satellites. Wikipedia says:

They head to a morning crossing time, sun-synchronous orbit (SSO) at an approximate altitude of 500 kilometres (310 mi).

According to the Wikipedia Planet Labs article, Flock 3p is the largest fleet of satellites to be launched in history.

called2voyage
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    The question is "constellation in space", not "fleet launched". Is Flock 3p a separate constellation from the other doves already deployed? They are not all orbit in a coordinated way? The following link is singular, not plural, but I don't know if that's necessarily indicative: https://en.wikipedia.org/wiki/Planet_Labs#Satellite_constellation Still, if the different "flocks" are deployed in a coordinated way, or spread out to improve coverage, wouldn't all flocks together represent a single constellation? – uhoh Mar 22 '17 at 22:34
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    @uhoh The Flock 1 fleet was considered a single constellation: https://www.nasa.gov/mission_pages/station/research/news/flock_1. I don't know if the other flocks were intended to join the same constellation or not. My guess is not, but if they are it is still certainly the largest constellation. – called2voyage Mar 23 '17 at 01:17
  • I can imagine the first flock was a pilot study as Planet Labs worked out how to manage and coordinate a group of satellites, and learned more about the hardware in space. I'll check the TLEs and see what's going on. – uhoh Mar 23 '17 at 03:30
  • I guess the problem is with the concept of constellation; it's usually understood as a set of satellites in specific rigidly defined orbits relative to each other. But once the number of satellites approaches a hundred, a stochastic approach becomes increasingly practical: have lots of satellites in semi-random orbits and the chance one is in optimal place at the right time is likely better than in case of traditional approach. Instead of 4 satellites taken to precise location, and equipped with fancy station keeping, launch 40 and just let them drift roughly where you want them. – SF. Mar 23 '17 at 18:01
  • Planet does perform stationkeeping within the orbital plane. See https://arxiv.org/abs/1509.03270 – pericynthion Mar 25 '17 at 04:41