
Long-lost U.S. military satellite found by amateur radio operator - wglb
https://www.npr.org/2020/04/24/843493304/long-lost-u-s-military-satellite-found-by-amateur-radio-operator
======
wrigby
I feel like "lost" is a bit of a misnomer here - this spacecraft was of course
being tracked still, and it only took a couple seconds of googling to pull up
the detailed info on the orbit from Celestrak[1]. There's even a nice
visualization available at [2].

1:
[https://celestrak.com/satcat/tle.php?CATNR=02866](https://celestrak.com/satcat/tle.php?CATNR=02866)

2: [https://celestrak.com/cesium/orbit-
viz.php?tle=/satcat/tle2....](https://celestrak.com/cesium/orbit-
viz.php?tle=/satcat/tle2.php?CATNR=02866&satcat=/pub/satcat.txt&orbits=1&pixelSize=3&samplesPerPeriod=90)

~~~
azernik
For a somewhat cooler visualization, which also gives you a comparison to the
GEO belt and other satellites but may be bad for browser performance, see
[http://stuffin.space/?intldes=1967-066E&search=1967-066e](http://stuffin.space/?intldes=1967-066E&search=1967-066e)

~~~
qubex
This kind of visualisation is fascinating, but it’s also (for reasons I shall
now explain) the root of a very serious misconception.

The misconception I speak of is the “junk in space” one. One sees images such
as these and clearly reaches the conclusion that we’ve immersed ourselves in a
thick fog of stuff which will soon become a barrier of fast-moving debris.

But... if one thinks about it, these objects are small, and if one were to lay
them all out upon the surface of the earth, they’d actually cover a tiny
fraction of it, and there’d be miles between each one. And furthermore, higher
altitudes define a larger sphere, and surface area depends on the square of
radius, so there’s actually far more distance available to these objects
(alternatively, to repeat the experiment on earth, one would need to
considerably scale down the already comparatively tiny objects and
satellites).

And on top of that, we have a whole third dimension to deal with, so it’s not
just one bigger sphere, but a continuum of spheres that all exist
independently of each other.

Which leads to my core contention: even visualising satellites as the smallest
graphical depiction possible (a single pixel) leads a viewer to vastly
overestimate their size, and therefore the density of objects that exist in
our sidereal neighbourhood.

And this irks me.

</rant>

~~~
tqkxzugoaupvwqr
What you did not consider is cascading collisions. If two high velocity
objects collide, a large cloud of high velocity debris orbits Earth. The cloud
expands and eventually parts of it collide with satellites, creating more
debris that collides with other satellites, creating even more debris.

~~~
qubex
Oh no I understand that very well, I’m well versed in statistical mechanics.
The thing is that the cross-section of the targets remain low, and therefore
the amplitude of the scattering matrix remains pretty low. It’s actually
pretty unlikely to successfully trigger off a divergent chain reaction. To use
a nuclear analogy, it’s the density is well below a critical density (or
rather, it’s far from a critical geometry).

------
jandrese
The "no comment" is really "everybody who worked on that has long since
retired and nobody is in the office to check the paper records, if they even
wanted to and were allowed to."

The communication protocols used by that old bird are probably still
classified.

~~~
jcrawfordor
A satellite of that age would have used a very simple analog repeater or
linear transponder, meaning that there is no communications logic occurring on
the satellite. Any digital modulation, and more so encryption, would be the
responsibility of the ground stations. This is still a common design pattern
for satellites, referred to as the "bent pipe" model since the space segment
is merely a "bend" with no logic, but it is subject to abuse by unauthorized
operators so there's usually some degree of at least authentication today.

Military satellites launched into the '80s continued to use analogue
transponders and, to some extent to this day, see unauthorized use. The only
real deterrent was the difficulty of obtaining inexpensive equipment for
satellite bands but the widespread use of DVB and VSATs changed that during
the '90s and '00s.

That said, all related documents may very well have been classified at the
time (owing especially to the lack of any authentication!) and even when
declassify-on dates pass there is often institutional resistance to going
through the motions of releasing this material, especially since Lincoln Labs
(a contractor) would not be authorized to do so and would have to forward the
request on to someone else. A more formal FOIA request, followed by appeals if
necessary, can often unstick these wheels since it creates a legal obligation
that a more casual media request does not.

~~~
unixhero
Dude out of curiosity who are you and how can I learn all the things you know.

~~~
dylan604
I knew a guy that was part of the beginnings of the cable frontier running
numerous cable headends. Any time he needs to align a new dish, he does it by
hand. He knows where a specific satellite is, and a particular signal coming
from it. Once he finds it, he pans the dish across the line of satellites
until he gets to the one needed. As you pan across the sky, you can use a
scope to see each of the birds come in and out of alignment. The
constellations are known, so you map out which ones are which. Some of the
signals are scrambled, but there's a lot to be learned, and if it is TV
broadcast, decoders are available. A lot of this gear is available
second/third/fourth hand now. With the right gear, it is possible to learn a
lot of this stuff on your own with some google searches. Learning to decode
what's already coming down is just a step on the way to learning about what
goes up.

Useless satellite trivia: from time to time, it becomes necessary to adjust
the orbit of the satellites (like a wandering disabled satellite). They do not
fire boosters to raise/lower the orbit directly as that requires too much
fuel. Instead, they speed up/slow down the horizontal speed to
increase/decrease altitude. With enough notice, they can do this very
incrementally and fuel efficiently.

~~~
JshWright
The necessary equipment is also crazy cheap at this point. You could easily
start listening to satellites with a $20 USB SDR dongle and a DIY antenna.

If someone wants a cheap way to learn orbital mechanics (like why you
accelerate/decelerate to raise/lower your orbit), pick up a copy of Kerbal
Space Program.

------
8bitsrule
I wonder if anyone's ever heard from SNAP-10. It was the first fission reactor
in orbit (1965). It had, uh, problems and was shut down after 43 days. In late
November 1979 it had a 'anomalous event', and it had 6 more in the next 6
years... releasing '50 trackable pieces'.

[0]
[https://web.archive.org/web/20170503083646/https://ston.jsc....](https://web.archive.org/web/20170503083646/https://ston.jsc.nasa.gov/collections/TRS//_techrep/TP-1999-208856.pdf)

~~~
emptybits
Great document. One of many eye-openers:

"The West German government sponsors a meeting called Safety Aspects of
Nuclear Reactors in Space, in Cologne. Nietrich Rex predicts that Soviet space
nuclear reactors will undergo 2-3 on-orbit collisions in the next 300 years.
Each will result in world-wide reentry of radioactive debris."

That's a prediction from November 1989.

~~~
Rebelgecko
I can't find a source after a cursory search, but IIRC the Soviet RORSATs are
still the second or third biggest source of space junk today (#1 being the
2007 Chinese test of an antisatellite weapon). A few of them had nuclear
reactors fail in dramatic ways, although a lot of their debris is just from
leaking coolant.

~~~
Ironlikebike
Per this document it appears that (frequent) Delta second stage explosions
were one of the most significant contributors. By 1981 27% of all tracked
debris (of orbital period under 225 minutes) were from Delta second stage
explosions. (I'm guessing these are considered high velocity debris). It's
quite interesting that NASA was surprised by this (asking McDonnell-Douglas to
find out why in May of 1981) considering how long they had been launching the
Delta rockets and tracking debris. From the document, NASA officials
continually approved work to track orbital debris, but often didn't give the
reports administrative attention.

------
themodelplumber
1965\. Wow. Watching and listening to that waterfall was fantastic. And by the
way, great use of links in the NPR article. I found a new blog to follow, a
lab I've never heard of, a Twitter account to check out, and _Gunter's Space
Page_, which we hopefully all know via intuition is a quality work to be saved
for later in-depth review. ;-)

~~~
raginalix
When I got my first rtlsdr dongle I spent hours just surfing the frequencies
looking for interesting signals and trying to decide them. It's a great hobby!

SDR has opened up a new frontier for me, it gives me the same excitement I got
when I discovered BBSs and then the internet.

I was lucky enough to have a project come up last year that required gsm/4G
and GPS simulation. I got budget to buy a bladerf and a nice SBC and built a
box that could simulate a GSM, 3G/4G basestation and simulate GPS.

~~~
themodelplumber
That's awesome! Especially since your work experience seems to integrate with
your hobby, and a very cool hobby at that.

Just to re-balance the universe a bit here, I almost stepped on my RTL-SDR the
other day, in a neglected corner of my workspace, and felt pretty guilty about
it ;-)

(Tangentially, I gave a cheap portable SW radio to my son the other day, after
not using it for a while. I was trying to find a favorite FM radio station to
demonstrate to him, and stumbled across one of the local emergency services
instead, in the 150 MHz range. Haha, no wonder the dial markings don't match
up at all. Now he's telling me what kind of makes & models he's hearing about
over the air...)

------
imjustsaying
This reminds me of another thing a lot of people have been noticing lately
with more time to look up.

What's been up with Venus? It's been really bright for weeks if not months
now.

~~~
teraflop
Venus is only a few weeks away from its inferior solar conjunction, which is
approximately the point in its orbit (recurring about every 19 months) where
it most closely approaches Earth: [https://in-the-
sky.org/news.php?id=20200603_11_100](https://in-the-
sky.org/news.php?id=20200603_11_100)

Interestingly, Venus' brightness is currently near its peak, even though the
conjunction itself is still several weeks away. At the point of closest
approach, the planet will be almost 3x bigger in angular area than it is
today, but we will be seeing a much smaller fraction of its sunlit side.

~~~
dcassett
That is one of Heinrich Dorrie's 100 Great Problems of Elementary Mathematics:

[https://www2.washjeff.edu/users/mwoltermann/Dorrie/MaxMinPro...](https://www2.washjeff.edu/users/mwoltermann/Dorrie/MaxMinProblems.htm)

------
CraigJPerry
I got interested in rf spectrum in 2014 and haven’t looked back. There’s just
so much fascinating stuff out there.

------
3fe9a03ccd14ca5
One of the satellites found by this sleuth:

> _Transit 5B5 was a US Navy navigation satellite launched by a Thor Able Star
> rocket. It carried a nuclear power source._

Wait what? Nuclear powered satellites? How do they safely dispose of these??

~~~
kjs3
Yes, it's a thing. Most of the deep space probes were radio-nucleotide
powered. Earth orbiting is less common for obvious reasons. One option is
boost to a parking orbit where it'll be stable and out of the way for a couple
of thousand years. But the stuff from the '60s was often "it'll burn up on
reentry (cross fingers) and it's a cost of doing Cold War business if a little
get's scattered around".

~~~
perl4ever
There are plenty of earth orbiting actual fission reactors, not like the RTGs
you have heard about.

There were quite a few sent up by the Soviets (from 1967-1988) and at least
one malfunctioned, failed to eject its reactor into a disposal orbit and
scattered radioactive waste across northern Canada.

Even the Soviets didn't _intend_ to send nuclear reactors to burn up on
reentry; I'd be surprised if that was anyone's plan.

[https://en.wikipedia.org/wiki/US-A](https://en.wikipedia.org/wiki/US-A)

[https://en.wikipedia.org/wiki/BES-5](https://en.wikipedia.org/wiki/BES-5)

[https://en.wikipedia.org/wiki/Kosmos_954](https://en.wikipedia.org/wiki/Kosmos_954)

[https://en.wikipedia.org/wiki/Kosmos_1402](https://en.wikipedia.org/wiki/Kosmos_1402)

"...44 kg of uranium had been dispersed into the stratosphere after the
incident..."

~~~
kjs3
I've more than "heard about" RTGs, and I'm well aware of the kind of reactors
that have been shot into space. We can argue the level of "intend", but in the
Cold War, the reentry of a nuclear reactor was considered an acceptable cost
of doing business.

------
sciurus
If you're intrigued by tracking satellites and their transmissions more
generally, check out [https://satnogs.org/](https://satnogs.org/)

------
tectonic
See also: [https://www.rtl-sdr.com/receiving-dead-satellites-rtl-
sdr/](https://www.rtl-sdr.com/receiving-dead-satellites-rtl-sdr/)

------
JoeDaDude
I guess that was before we had responsible satellite disposal.

[http://www.esa.int/ESA_Multimedia/Videos/2017/04/Space_debri...](http://www.esa.int/ESA_Multimedia/Videos/2017/04/Space_debris_2017_-_a_journey_to_Earth)

------
CalChris
Reconnecting with an old satellite has been done before. Perhaps it be done
again.

 _The International Sun-Earth Explorer (ISEE-3) satellite was launched on
August 12, 1978, and was originally meant to study the Earth 's magnetosphere
from the L1 Lagrangian point between the Sun and the Earth, where the gravity
of both bodies cancel each other out._

[https://www.vice.com/en_us/article/pga3m7/techno-
archaeologi...](https://www.vice.com/en_us/article/pga3m7/techno-
archaeologists-used-an-abandoned-mcdonalds-to-hijack-a-satellite)

------
analog31
This has me puzzled:

>>> Confirmation will occur at ~0445 UTC this evening when the satellite
should pass through eclipse.

Shouldn't it be stationary, if it's in geostationary orbit? Or is it just that
the satellite has drifted out of that orbit over time?

~~~
azernik
The article says GEO, but actual quotes _in_ the article say "GEO graveyard
orbit". What this means is that, at the end of the satellite's service life,
it was boosted into a lower (in this case [1]) or higher (also common) orbit
out of the way of the GEO line. There isn't much space in GEO, as it's a one-
dimensional space [2] - only true anomaly (position in the orbit) can be
varied. So you want to free up the slot once you're not using it anymore.

[1] This particular satellite is
[http://stuffin.space/?intldes=1967-066E&search=1967-066e](http://stuffin.space/?intldes=1967-066E&search=1967-066e).
Note the orbital period - it's shorter than a sidereal day of 1436 minutes,
which means this is a lower orbit. It's also slightly inclined to GEO, which
reduces the chance of collisions even further.

[2] By contrast, the set of Keplerian orbits is generally a six-dimensional
space, with singularities at eccentricity = 0 and inclination = 0. Well, also
technically at semi-major axis = 0, but that's not a physically possible
"orbit".

~~~
yellowapple
Are lower-than-GEO graveyard orbits common? I mean, I guess they are, judging
by stuffin.space, but my intuition would be that it wouldn't take any more
fuel to put a satellite in a higher-than-GEO graveyard orbit (and thus further
minimize the risk of collision), no?

~~~
azernik
No particular reason why a higher orbit is any better than a lower orbit. As
long as you're a good 1000 kilometers away from the GEO belt at closest, and
preferably a little inclined so that closest approach only happens ~2 times a
day, both high and low graveyard orbits are equally good for avoiding
collisions.

------
jplayer01
> "The reason this one is kind of intriguing is its telemetry beacon is still
> operating," Tilley says.

What exactly is a telemetry beacon, and what kind of data would it be
broadcasting?

~~~
merlincorey
It's at a minimum simply a high signal on a certain frequency indicating the
device is there and then you use math to gather telemetry data (position,
speed, etc).

At most, it's packets of data that indicate telemetry data such as position,
speed, temperature, and the current state of any instruments on board.

Telemetry data is typically pushed out at regular intervals to allow it to be
recorded and graphed in a time series.

------
anonymousiam
Rick Rhodes could really build ‘em!

