Ham Hears Mars Orbiter 45 Million Miles From Earth

Richard L. James writes "As reported on the Mars-net email list Flight Refuelling Amateur Radio Society's resident satcom + WLAN guru Paul J. Marsh (M0EYT) has managed to detect and receive NASA's Mars Reconnaissance Orbiter on X band at a staggering range of 45 million miles from Earth using a home made receiver setup and a RFspace SDR-14 software radio."

Comments

So...

[ToasterofDOOM]

...how soon can I get this sort of range/reliability for my home Wifi?

Re:So...

[rossdee]

Even if you could, ping times would suck. 8 minutes or so for the round trip.

Re:So...

[pnewhook]

That pisses me off too. We can get beautiful hi-res pictures from the moons of Saturn, but I can't get a decent cellphone connection downtown.

Nice ...

[Anonymous Coward]

and here I can't get a decent fucking picture from DirecTV.

Obligatory

[Anonymous Coward]

"Can you hear me now?"

Re:Obligatory

[ToasterofDOOM]

Give me a couple of minutes, we're getting some crazy high lag. So much for pwning those martian gamers.

Re:Obligatory

[aarku]

More obligatory: "Mmmmmm.... orbiting ham.... *garalrahhararar*"

Security risk?

[nonother]

We better start encrypting our space chats or the aliens will surely hear us.

Re:Security risk?

[user9918277462]

All NASA communications are encrypted. One of the highest priorities during recovery of the Columbia wreckage was to find and secure the NSA "black box" that encrypted radio traffic between the shuttle and ground control.

Can you imagine the damage some antisocial radio vandal could do to the Mars Rovers, for instance, if the command traffic was sent in the clear?

Re:Security risk?

[mboverload]

Oh, nevermind. You were refering to a civilian finding and keeping it then reverse-engineering it.

Though your point is still mute. I doubt they use the same scheme for all their assets. That would be retarded.

Re:Security risk?

[Lehk228]

apparantly they use the same symmetric key for more than one vehicle.

Re:Security risk?

[Anonymous Coward]

you're ... moot.

/me out

Re:Security risk?

[MegaFur]

Though your point is still mute.

"mute" is not the same word as "moot". They have different meanings and different pronunciations.

Re:Security risk?

[cyclone96]

I'm sort of splitting hairs here, but only the command link is secured on most NASA satellites. The telemetry back to the ground isn't necessarily encrypted (it isn't on the shuttle and ISS), although you'd definitely need to have some pretty expensive equipment and know-how to decode the carrier into anything useful (like voice and data). Then again, it's only fun because it's hard...

There's a few more details on how it works for ISS in a NASA training manual here. (It's a 6 Mb pdf, communications is section 4).

Re:Security risk?

[mwilliamson]

You'd think they'd be using some form of PKI, not simply relying on a symmetric cipher. Revoke keys...

Re:Security risk?

[Detritus]

All NASA communications are encrypted.

Bullshit. You have absolutely no idea as to what you are talking about.

Can you imagine the damage some antisocial radio vandal could do to the Mars Rovers, for instance, if the command traffic was sent in the clear?

More bullshit. Many spacecraft command uplinks are not encrypted. You need to know a lot of things and have some very expensive hardware before you are going to be able to command a spacecraft. Just knowing the uplink frequency is a small piece of the puzzle.

Re:Security risk?

[bombadier_beetle]

As someone who consulted at JPL and helped develop a good amount of DSN protocols, I can second this.

Re:Security risk?

[nacturation]

Someone just learned a hard grammer lesson on slashdot for EVERYONE to see - how humiliating.

Meanwhile, in another post, a humiliating spelling lesson is underway.

Re:Security risk?

[dr_d_19]

All NASA communications are encrypted.

I broke that encryption years ago. According to my findings, proximity and movement correction data was sent as YARDS and not METERS.

Re:Security risk?

[Lehk228]

more concerned with someone finding the key from the crashed shuttle and changing all the satellite imagery data to gaping anus imagery

Transcript

[coolraul]

Orbiter: "Beep beep beep bo beep" Base station: "Da deet da da deet deet da"

Re:Transcript

[mboverload]

Base Station: 01000111011011110010000001100110011101010110001101 10101100100000011110010110111101110101011100100111 0011011001010110110001100110

Orbiter: 01000101011101110111011100100001001000000010000001 0011100110111100100000011101110110000101111001

Base Station: 01101111011011010110011100100000011011000110111101 10110001111010

Re:Transcript

[dogwelder99]

Orbiter:

Dear Sir,

Confidential Interplanetary Business Proposal

Having consulted with my colleagues and based on the information gathered from the Martian Chambers Of Commerce And Industry, I have the privilege to request your assistance to transfer the sum of $47,500,000.00 (forty seven million, five hundred thousand Earth dollars) into your accounts. The above sum resulted from an over-invoiced contract, executed, commissioned and paid for about five years (5) ago by an alien contractor. This action was however intentional and since then the fund has been in a suspended account at The Central Bank Of Mars...

Re:Transcript

[TubeSteak]

Base Station: Go fuck yourself
Orbiter: Eww! No way
Base Station: omg lolz

My Response: 01010010011011110110011001101100011011000100001101 10111101110000011101000110010101110010011110100010 00010010000100100001001100010011000100110001011001 01011011000110010101110110011001010110111001101111 0110111001100101

Figure it out yourself
http://nickciske.com/tools/binary.php

Re:Transcript

[pharwell]

Orbiter: "Beep beep beep bo beep" Base station: "Da deet da da deet deet da"

Sting: "De do do do, de da da da"

Re:Transcript

[NeuroManson]

Are you sure it wasn't "Bah-weep-granna-weep-nini-bohn"?

Re:Transcript

[hazem]

And THAT's why we don't want to give Haliburton the Mars contracts too...

Re:Transcript

[tnsimonson]

Base Station: So what're you wearing?

Orbiter: I've got on a slinky little number.

Base Station: Aight, I put on my robe and wizard hat.

WHAT LINK!?!

[Anonymous Coward]

Jesus fucking christ! What link do they want me to click?! My slashdot honed senses are confused by the lack of more then one link in the article summary!!!

Oh, wait, nevermind, since when did I read articles? Crisis averted! :)

Re:WHAT LINK!?!

[ValiantSoul]

Just open them all in new tabs and then close them after checking if theres pictures - thats what I do : )
/. effect!

Re:WHAT LINK!?!

[Pollardito]

you must be new to WikiDot

Re:WHAT LINK!?!

[Anonymous Coward]

Please keep your language clean and a little bit less offensive. The generally good taste in communicating is what makes /. such a good forum. What you wrote was way over the top and not even close to acceptable.

How long before he is silenced?

[pawstar]

So, how long will it take for this guy to be reprimanded for space war driving of satellites ?

That is actually pretty cool

[Talisein]

I bet he's getting high-fives and beers from all his geeky friends. ... I wish I were one of those friends. ;)

Re:Slashdotted

[Jeng]

Which one?

So?

[Voltageaav]

So what? This guy's basicly just taking his work home for fun. Yeah, he tinkered and built one on his own, but he should be able to if he's the NASA expert on it.

Re:So?

[uhfsatcom]

Hi Voltageaav, you have misread the context of the article, I built the receiver and have no connection with nasa at all - it was done out of technical curiosity just to see if it was possible with simple equipment to hear anything, the answer turns out to be a "yes".

regards
Paul (www.uhf-satcom.com contributor)

Just like Apollo

[Anonymous Coward]

How many of you remember the articles in QST and Ham Radio from the 1970's about the ham radio operators that received and decoded the pulse-coded modulation transmissions directly from the moon during the Apollo missions? Yeah, I think we really did go there.

This new feat comes on the heels of the success of ham radio in Louisiana. I've been licensed since high school in the early 1970's. These new-fangled computers are nice and convenient, but nothing beats ham radio! It works where nothing else will.

Ray

Re:Just like Apollo

[JourneyExpertApe]

How many of you remember the articles in QST and Ham Radio from the 1970's about...

I'm willing to wager: not many. For most slashdotters, the first season of Friends is retro kitsch.

"H3y, r3m3mbr wh3n w3 w3r3 k1d5 wh3n 7hey 1nv3n73d dvdburn3rs?"
"n0, dvdbyrn3rs h4ve 4lw4y5 3xis73d. PWN3D!!!!11"
"0h y34h, i f0rg0t."

Re:Just like Apollo

[Kadin2048]

You do know that the license exam is -- for anyone with a basic understanding of electricity -- pretty simple these days. In fact it's probably somewhat easier than the one you studied for in the past, especially if you spent a lot of time practicing the Morse code. You'd just need to memorize the band plan and you'd probably be able to go down and take the test. You could do it in a weekend, quite easily.

I'm very surprised that more geeks don't go and take the test, if you're even moderately interested in messing around with radio or wifi stuff. At the very least, you can legally boost the power on your 802.11b setup (on certain channels).

Although I'm not sure if it's totally up to date, here is a site where you can take sample tests:
http://www.qrz.com/testing.html

The question pools aren't that big, so if you take it a few times over you can basically exhaust all the available questions for any given test (or at least you'll start seeing repeats or very similar questions).

Re:Just like Apollo

[John Hasler]

> "How many of you remember the articles in QST and Ham Radio from
> the 1970's about..."

> I'm willing to wager: not many.

At least one.

Space Modulator

[tlynch001]

The article doesn't mention how he also needed a Uranium PU-36 Explosive Space Modulator

Whick link to click ?

[gibodean]

It's nice having so many links embedded in the summary, but which one links to where it's actually reported ? I'd expect a link on the "reported" word.....

Re:Whick link to click ?

[Anonymous Coward]

I opened them all in separate tabs, realized how many there were, and then proceeded to read none of them.

When is too much references too much ?

[RedVortex]

Can somebody point me the correct HREF to click on ?

You made your point dude, you're good at linking sites to your posts... :-)

RedVortex

Start eating your chips...

[postbigbang]

because that's one helluva Pringle's can. Defcon contests, you're over.

Re:That is actually pretty cool-Geek Cred.

[icepick72]

You're absolutely right. Money isn't the most important thing in life ... but it's sure WAY ahead of whatever's in first place!

The problem...

[staticsage]

The problem with this layout is that there's too much shit to click on. Seriously, who's ever going to click on all those links? The worst blogs are the ones that make every other word a hyperlink to another website so by the time you finish reading this sentence, you've forgotten what you were reading, or why you were reading it in the first place. Hey, this article is great but you know what would make it better? If I could read another article in the middle of it. Great design, morons.

Are you insane?

[955301]

The guy, a human being with clothes and bad breath and pimples as a kid and all of those things that level the playing field for all of us, is communicating with something 45 million miles away!

Even the most boring, predictable, well-funded case of this occurring should be celebrated with what is left of the adverturer in you.

"So what". Puh! Why exactly are you at Slashdot then?

Re:Are you insane?

[Ibby]

Exactly. If we can communicate with it, we can hack it. I wonder if it's interested in some v1agra...

Worked All Planets Yet?

[wa2flq]

Gonna need a lot fo postage on that QSL Card....

Yay for Amateurs!

[drwho]

I think this is great. It shows what's possible, even without a huge budget. I wish I could read more about it, but the sites have all been slashDOSed.

But just because they guy isn't paid to do this, and didn't spend a million dollars on the equipment, doesn't mean that anyone can do it -- setups like these are tricky. I imagine he had ot capture a lot of data, and use some really powerful computer for signal processing.

Now, if he can send signals BACK to mars, and have them interpreted by beings or equipment there, I'd be even further impressed.

I'd like to claim that this is a victory for ham radio. In a way it is, as it is a radio accomplishment and the fellow is not paid for this. But as it doesn't involve any transmission, it's more of an SWL (ShortWave Listener) accomplishment than an Amateur Radio accomplishment.

Re:Yay for Amateurs!

[uhfsatcom]

HI,

Yep its probably a victory for ham radio - since I'm licensed and operate >1GHz only, its experience with building ham transmitters / receivers etc that gave me knowledge etc, to build an 8.4GHz rx. The whole project was done to see if it was technically possible to build a receiver - I've not really got the time / interest to delve into the telemetry formats or to work out how to decode the tt&c data.

Next, I'm waiting for the 'New Horizons' mission to pluto, that will provide an interesting signal to track for a number of years.....

regards,
Paul (uhf-satcom.com contributor)

Whoa!

[dookus]

Pigs' hearing is *that* good?

Not quite

[slightlyspacey]

As with most things in life, the correct answer is "it depends". All NASA communcations to/from the shuttle are NOT necessarily encrypted but can be. Uplink from the ground to the shuttle always is encrypted (we don't want someone sending bogus commands). In addition, the crew has the option of disabling all commands coming from the ground. Direct downlink from the shuttle to the ground can be encrypted but that is not always done. It depends on the mission configuration. DOD-based classified missions back in the 80s always were encrypted on both the uplink and downlink.

There are also other communications paths between the shuttle and the ground. Indirect communications, known as forward and return links via, TDRSS are always encrypted.

Re:Not quite

[slightlyspacey]

You are correct of course. In the case of the space shuttle, it's just easier, cheaper, and safer to encrypt the entire uplink using the existing crytographic device and its corresponding hardware key. The cost of the integration of a command authentication mechanism using a crypto signature with the existing shuttle hardware and software would be prohibitive.

Power being wasted?

[Ruff_ilb]

If we're broadcasting a signal so strong that some random dude can pick it up at home with homemade equipment, isn't that an unnecessary amount of power being wasted on transmissions? I don't know about the actual power consumption, but seriously, when your launch costs are in terms of millions (if not billions) of dollars, you shouldn't have this sort of ineffeciency.

Re:Power being wasted?

[NixieBunny]

Perhaps you meant to say "some random microwave receiver expert", not "some random dude". This is not everyday work - I build stuff like this for radiotelescopes. But I'm surprised that he used a tiny 1 meter diameter dish to receive the signal - I was expecting at least a standard old-fashioned 3 meter satellite dish to have been used to improve the signal level at the receiver.

I am waiting patiently for the equipment webpage to load so that I can see what sort of filters he used. That's the main tricky part for doing such an experiment - you need to build a custom filter to reject everything that isn't in the spacecraft's frequency band. The rest of the equipment is apparently a modified satellite TV receiver and a generic software radio.

Re:Power being wasted?

[uhfsatcom]

Hi, re the bpf, its only a 2 cavity filter made in wg16, cf=8420 with about 50MHz bandwidth, and RF coupled in and out via the standard probed with appropriate matching screws. Using that dish, the signal isnt that strong, its detectable though on an FFT as per the article. There is a nice page on x-band space probe reception with some example audio at http://www.setileague.org/photos/probes.htm
The next plan is to try to hear the orbiters that are currently at Mars, but that will need the 3.7m dish.
regards,
Paul (uhf-satcom.com contributor)

Communication mode

[earthstar]

I have always wondered,what type of commmunication is to communicate with far far away missions like Hubble? How does the signal reach earth?When signals are travelling through millions of miles through space ,wont it weaken to nothing?

Re:Communication mode

[rusty0101]

There is a bit mroe to it than just ading more power gets you a higher data rate. If you send a .25 watt signal with all the power in a .5 khz bandwidth signal, you are not going to get more than about 300 bits per second data transfer. Increasing your power level does not improve the data rate, though it may improve your receive capability over a longer distance. I.e. increasing the power from that original .25 watt to say 25 megawatts doesn't improve the data rate, but it may mean you can receive the signal somewhat further away.

If you want to increas the data rate, you need to expand the transmited bandwidth. Most of the comercial handheld 2-way radios out there use about a 2.5 khz bandwidth, which is OK for voice, though Hams and older (much older actually) comercial equipment uses a 5 khz bandwidth for voice. This bandwidth also works fairly well for slow scan vidio, which is basically single images sent over a period of between 5 and 20 minutes, depending upon the data rate, (1200 bps, or 9600 bps are common on ham frequencies) and image resolution and color depth.

If you want to send live video, you have to step up the bandwidth significantly. Standard TV uses a channel separation of 6 mhz, You can do a lot better with compression, and by reducing the frame rates. If you are video conferencing over your dsl or cable modem line, with an uplink cap of 128kbps, the signal your video chat partner receives is going to be somewhat less impressive than they get off the air for TV.

Now if you want to reach the same distances with the higher bandwidth signal as you would with that .5khz wide signal, you are going to need more power spread across that bandwidth. Going to a 2.5 khz signal means you will need a 1.25 watt signal. 5khz means a 2.5 watt signal. For that uncompressed live video feed, if you use a 5mhz wide signal (this gives a comfortable 1 mhz separation for most people, which is probably sufficient to toss in an audio stream of some sort) you are going to need a 2500 watt signal to start with. If you need to be able to receive it at a significant distance, you will need to be able to either increase the radiated power, or the gain of the signal in the direction the receiver is located in. Gain is measured in db, and for the purposes of this posting are compared to an omnidirectional signal. If you can get an effective four times the power radiated in the direction of your receiver, you have effectively increased the gain by 6db. (3db is double the signal.) You can also improve the signal reception by increasing the gain of the receiving antenna. In the case of the article the improvement in gain was done via a 1 meter offset sattelite dish.

For the most part the desire is to get the gain of the desired signal to be some power level over the noise floor of the environment you are working. The noise floor is generated by background radiation, as well as radiation of the environment you live in. If you happen to have mountains between you and all the local cities, or can work from an island over the horizon from significant RF sources, you can improve your separation somewhat. That doesn't help with the univeral background radiation, so he had to add some filtering to lower the signal level for signals outside of the desired bandwidth. As he was able to reduce those sigals by an effective 50db with his waveguide filter, he significantly improves his ability to receive the desired signals.

Granted he still has to be able to point the receiving system at the sending system. Sounds like he was able to.

The radiated power that the Mars Express transmits with is published data, as well as the effective gain of its transmitting antennas. The range between earth and Mars is reasonably easily calculable. It sounds like M0EYT got the rest of the calculations to work out as well.

Some of the above is not exact. Feel free to do more research to learn more about it yourself.

-Rusty - kc0vcu

Smirnoff

[slashdotmsiriv]

In Soviet Russia the orbiter hears you. oh..wait...hmmm

Muppets?

[Jah-Wren Ryel]

Did anyone else read that title as:
"Ham Nears Mars Orbit 45 Million Miles From Earth"

I thought it was going to a story about Piiiigs in Spaaaaace!

Re:Muppets?

[tokul]

> Did anyone else read that title as:
> "Ham Nears Mars Orbit 45 Million Miles From Earth"

With sufficient thrust, pigs fly just fine. (rfc 1925)

I understand

[Anonymous Coward]

Slashdot is a public forum where everything is dicussed in far too much depth and 90% of it is pointless

FAKE!

[Linker3000]

Working on the (alleged by some) premise that we never went to the moon - how do we know that NASA isn't pumping out a fake, weak signal from a research lab just to fool us!!? I won't believe it until we get some triangulation on that signal!

The real question is...

[mtec]

Was the antenna in a Spiral or was it flat and Deli thin?

Oh, and I'll bet all he could hear was 'The Cure'.

I'm very very sorry. I'm such a ha... never mind.

Betting time again....

[Moggie68]

How long until this guy receives more than the Mars orbiter signal...a visit from FBI? I give it 14 days, tops.

Re:Heretic!

[The_Wilschon]

Mars still moves in a geocentric view. So you would still achieve a different relative Earth/Mars position.