In this answer there is a link to an amateur radio website listing what looks like satellites of interest to that community. The list is long (over 400 lines) and has a designator character in the last column. The key is

      Active (*)
  Deep space (d)
     Failure (f)
    Inactive (i)
 Non-amateur (n)
  Re-entered (r)
     Unknown (u)
 Weather sat (w)

I saw Deep space (d) and got curious! I searched and found four entries with the Deep space designator. They are listed below for convenience, but take a moment to view the original site because I may have missed something.

Are these really deep space amateur radio satellites?

note: you can scroll left and right in the gray boxes. The lines are about 121 characters long. --->>

Satellite               Number   Uplink            Downlink          Beacon      Mode                  Callsign
-----------------       -----    -----------       -----------       -------     -----------------     ------------
UNITEC-1                36578       .             5840.000          5840.000     1200bps AFSK,CW       JQ1ZUN           d
4M-LXS                              .              145.980              .        WSJT-JT65B            LX0OHB           d
SHIN'EN2 (FO-82)        40320    145.940-145.960   435.280-435.260   437.385/437.505 Transponder,WSJT/CW  JG6YIG        d
ARTSAT2-DESPATCH(FO-81) 40321       .                 .              437.325     CW                       JQ1ZNN        d
  • $\begingroup$ 30 seconds and a search engine got me this confirmation on the Unitec-1: unisec.jp/unitec-1/en/top.html $\endgroup$
    – Hobbes
    Commented Jul 26, 2016 at 11:32
  • 1
    $\begingroup$ @Hobbes If nobody wants to post a decent answer, then I'll write one - they have "the google" and "the interweb" where I live too. However I think there are some interesting, compelling, and... wait for it... SXSE stories here, and I'm lousy at writing about interesting stories. So there's a great chance someone can do it better. Cheese-shaped OSCAR at 4.7 million km - amazing! $\endgroup$
    – uhoh
    Commented Jul 26, 2016 at 12:01
  • 1
    $\begingroup$ At this link I find confirmation that there are indeed deep space HAM radio satellites. But I would love to know why. The only benefit I see is that the time during which it can be contacted will be longer. $\endgroup$ Commented Jul 26, 2016 at 13:57
  • $\begingroup$ Like the famous quote "...but because they are hard." Now why one of them is Cheese shaped - that deserves its own question. Luckily we have a space-art tag ready for it. $\endgroup$
    – uhoh
    Commented Jul 26, 2016 at 14:02

3 Answers 3


They are in fact in deep space, but there were all carried there by some other mission already heading to deep space as a secondary payload. They were all university payloads, thus operating on the amateur radio frequencies, but not of particular use to more amateur operators.

For reference, one of the easiest ways to tell an amateur satellite is to look for an OSCAR number. OSCAR was the first amateur satellite, Orbital Satellite Carrying Amateur Radio. FO-81 and FO-82 are OSCAR numbers (The first letter can vary, it depends on the organization that built it usually).

  • $\begingroup$ Eeeeeexcellent! $\endgroup$
    – uhoh
    Commented Feb 9, 2018 at 13:58

The answer is no they are not Ham Radio Satellites, but they are amateur built satellites. These satellites are indeed in deep space, however I would like to point out that there is a difference between 'amateur satellites' and 'amateur radio satellites.' I call them 'amsats' and 'hamsats' respectively. Amsats are built by amateurs, ie non-commercial, non-government, non-military. They are usually built by university teams. They often use amateur radio frequencies for their control and telemetry radios but they are not intended for amateur radio operators.

Hamsats, may have scientific experiments and payload, but they also have amateur radio beacons or transponders intended for amateur radio operators to carry out conversations or to transfer signals such as TV or data. All currently active amsats are in Low Earth orbits (LEO). Hamsats are often built by amateur radio operators in conjunction with university teams.


I think the problem here is not the question, nor the interpretation of the term "AMSAT". The problem we are facing is the definition and classification of "deep space" at the quoted source

This seems to be a website ran by an Radio Amateur with call sign "JE9PEL".

So the question "are these satellites really deep space" comes down to:

  • what is JE9PEL's definition of "deep space"
  • what criteria did JE9PEL use to classify those satellites as "deep space"

Without contacting this individual, one cannot reliable answer the question of the OP.

Based on internet searching you can guess and compile some initial conclusions:

  • UNITEC-1 was developed to be a competition between universities, to see who's computer would last the longest in harsh conditions of a Venus orbit. Given that it was deployed as such you may assume it has not entered back to any orbit near earth, and if you define a Venus orbit as "deep space" then the source is likely to be correct
  • 4M-LXS was a Lunar fly-by project. It is uncertain if this bird has re-entered into earth orbit, or that it has gone off on another/unknown trajectory. The project seems to have ended, and links are no longer working. However you can find a website which lists this satellite as active, which would confirm the premis of this answer: how much do you trust the source of the original question.

I did not search for the others, as I do believe that this would not add to the answer of this particular question.

The only conclusion I can give is: without further details; the source of the data of which is the basis of this question is dubious.

  • $\begingroup$ Actually, in this Stack Exchange site & space exploration in general, deep space has a fairly well definition; anything beyond cis-lunar space. So something bound to, and in orbit around the Earth, or the Moon, or the Earth-Moon Lagrange points would not be deep space. But something at the Sun-Earth Lagrange points (which are really modified heliocentric orbits) or in a plain vanilla orbit around the Sun would be deep space. So there really isn't a question about the term here. The question is where in space were the satellites when they were being used. That's what needs to be tracked down. $\endgroup$
    – uhoh
    Commented Feb 9, 2018 at 8:26
  • $\begingroup$ OK I will read your answer shortly. Thank you very much for taking the time to look into this and write up a nice post, this is great! $\endgroup$
    – uhoh
    Commented Feb 9, 2018 at 8:27
  • $\begingroup$ @uhoh It is not about what we, you, and experts on this site consider "deep space" it is about the source. So this is certainly a question about the term as you do not know how the source is defining and using that term. $\endgroup$ Commented Feb 9, 2018 at 8:31
  • $\begingroup$ I'm going to stick to the generally accepted definition. I'm interested if the spacecraft were in deep space when they were used. I only mention the source for background: "I saw Deep space (d) and got curious!" It doesn't matter what the source says, what matters is the trajectory that the spacecraft actually had at the time they were used. Just the facts, not the interpretation. $\endgroup$
    – uhoh
    Commented Feb 9, 2018 at 8:36
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    $\begingroup$ @uhoh, I think you misinterpreted my intention here. I know you know the definition of "deep space". I know that if you ask on this site; everyone knows. What I do not know is if JE9PEL uses the same definition. I do not know how JE9PEL has classified those satellites as (d). I do not question you, I do not question the general definition of "deep space" on this site. I do question the source. I would also be interested to know what sources the source has used. $\endgroup$ Commented Feb 9, 2018 at 8:49

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