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A nano-satellite that lets you take Earth images and "tweet" from space, then inflates a visible balloon, and de-orbits cleanly.
A nano-satellite that lets you take Earth images and "tweet" from space, then inflates a visible balloon, and de-orbits cleanly.
2,711 backers pledged $116,890 to help bring this project to life.

We Have Identified SkyCube

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I didn't expect to write this update.

For most of the past 3 weeks, there had been no definitive contact with SkyCube from any ground station. Although some 915 MHz signals were heard when a candidate object passed overhead, none of them were conclusive. We've been unsure which of the 5 objects released from ISS on Feb 28th is really SkyCube, and all information provided to us by other teams indicated that the official designation of 39569 = SkyCube is wrong.

On March 14th, a Russian amateur radio operator (Dmitry Pashkov, UB4UAD) reported a 915 Mhz signal which looked suspiciously like a SkyCube telemetry tweet. But the signal was not decoded, and the date/time it was received, plus the direction which his antenna was pointing, indicated that the signal came from the wrong satellite (specifically, 39569, identified as LithuanicaSAT-1).

On Friday, March 14th, we used the 60-foot radio dish at Stanford University to attempt contact. No response was received. We had been preparing to declare the satellite lost.

Back from the Dead

This all changed last night. While reviewing our server logs, we discovered that the Central California ground station had recorded a response from SkyCube on 27 March 2014 at 07:52:47 UTC. At that time, the station was pointed at object 39567, at an elevation angle of about 33 degrees and a range of 700 km.

The ground station received a 915 MHz signal, which was was digitized, decoded, and passed to our server along a secure SSL connection. It was an encrypted 16-byte sequence. Our server decrypted the sequence to the following meaning:

Battery voltage = 8250 mV
Solar panel current = 0, 0, 0, 1, 0 mA
Date/Time = 2014/01/27 14:55:15
System uptime = 2301542.12 seconds
Processor temperature = 16.7 degrees C

Here's what this means: the battery was near fully charged. The solar panel current readings, all near zero milliamps, make sense because the satellite was passing over the ground station at night. The low processor temperature is consistent with this - we see temperatures of 25 - 40 C when testing our satellite in sunlight.

SkyCube is programmed to think it's midnight, January 1st, 2014 when it first powers on. If this happened when SkyCube deployed on 28 Feb 2014 at 07:30 GMT, then it would think the current date is Jan 27th when the transmission was received on March 27th. (We never sent it a SET_TIME command to tell it the correct date.) The system uptime of 230154 seconds means that the processor has been running continuously for 26.7 days.

This data packet came over an SSL-secured connection from the IP address of the Central California ground station. To get passed to our server, its first 8 bytes had to be correct. The packet decrypted and passed CRC validation. The decoded data was sensible. There's just no way this could be anything but a response from the real SkyCube in orbit.

Why now? What's next?

SkyCube is still alive, in space, and has been operating for at least 27 days. And we know know, definitively, that it's NORAD object 39567. But why are we only hearing from it now?

Partly, it's because we've spent a lot of time listening to the wrong objects. Until now we could not prove which one was ours. And we now also suspect that only one or two of SkyCube's solar panels deployed on day 1. That would explain why so many initial contact attempts failed. Only one or two radio antennas were exposed, and the satellite had to be facing just the right way to pick up a signal from the ground.

Right now, we're sending commands to release the solar panels. Those may or may not work. If the solar panels & radio antennas remain stuck, then occasional, sporadic broadcasts may be all we ever get. But this is still a huge improvement from where things stood 24 hours ago. We now know definitively which satellite is ours, and where it's located at all times. We know that it's been operating for many weeks and survived hundreds of orbits. We know that the ground stations and server infrastructure designed to talk with SkyCube's C2 radio on orbit can actually do so; this had not been proven before.

And we also now know that an amateur team can build, manifest, and orbit a satellite that functions in space, on a shoestring budget funded by volunteers around the world, a few dollars at a time. No matter what happens next, that's groundbreaking history that you helped create, and you should all feel proud to be a part of it.

Thanks for making it happen.

-Tim, Rouslan, Scott, Kevin, Mark, and the rest of Team SkyCube

William Hector, Steve, and 78 more people like this update.

Comments

    1. Creator Montgomery A. Lee on June 12, 2014

      It's been over 3 months without an update. I'm guessing that it's dead and the SkyCube folks have disbanded, as no one is responding.

    2. Creator Tim DeBenedictis on April 20, 2014

      Greg, Francisco - You're due for an update soon. However, we'll be attending the CubeSat Developer's Workshop at Cal Poly University this coming Wednesday and Thursday, April 23-24. Conference preparation has consumed most of our time over the past 10 days.

      We continue to send "deploy solar panels" commands to SkyCube from all ground stations when the satellite is passing over them. One ground station is enhancing capabilities with a new 3-meter dish, and we're still awaiting results from that effort.

      I'll present a more complete update after next week's conference. Meanwhile, if anyone is near San Luis Obispo, California on April 23rd or 24th, I'd be glad to answer any questions you may have in person.

    3. Creator Francisco Eduardo M S Spuny on April 19, 2014

      Did the solar panels open ?

    4. Creator Greg Parikh on April 14, 2014

      Hi guys
      Any updates on progress?

    5. Creator Jason Creager on March 31, 2014

      116,890 congratulations Tim and SkyCube Team!

    6. Creator Idan Cohen on March 31, 2014

      Well done guys! This brought me back to my days as a satellite operator in the army. I still remember counting the first orbits and those ever growing numbers eventually getting into the thousands and tens of thousands. Exciting times!

    7. Creator Chris Felstead on March 31, 2014

      What a great post-your second last paragraph says it all-people power got it up there-lets hope it can open those damn solar panels:-)) i am in awe of your persistence-a great achievement no matter what happens next !!!

    8. Creator Alex on March 31, 2014

      Wow! That's really good day!
      We're waiting for the next updates

    9. Creator James Tacker on March 31, 2014

      Very good news indeed. We (through you all) put a satellite into orbit, and are receiving signals from it. I remember being a young boy and hearing the beeps from Sputnik long ago, and now we've been able to launch a satellite into orbit through donations by individuals. I'm sure you men and women who worked on this project have a real appreciation for the difficulties that a journey into space presents. If you can get it to deploy the solar panels and antenna, perhaps Sputnik will be far surpassed by SkyCube! Congratulations to all involved!

    10. Creator Terry Gray on March 31, 2014

      Well done, team! Every tiny step exploring our place in the universe is awesome. Just finished another viewing of Ron Howard's Apollo 13. I am always amazed at the accomplishments in space in the 1970's with all the computing power a warehouse can hold at their fingertips. Back when "booting up" really meant getting out the boots.

    11. Creator curtis on March 31, 2014

      That. Is. BIZARRE. That being said, all's well that ends well. I'm having a celebratory bowl. Good job, guys! Hats off to the technical team!

    12. Creator Jolea M Harrison on March 30, 2014

      That is good news indeed! Space is tricky, right? I'm so glad you didn't give up. Looking forward to the next update! Congrats!!!!

    13. Creator Matthew Cimone on March 30, 2014

      Amazeballs! That's fantastic. Good work, team! I hadn't lost hope!

    14. Creator Timothy Toler on March 30, 2014

      WONDERFUL! Congrats SC team :)

    15. Creator Keith Nealy on March 30, 2014

      Great! Now let's hope you can get its proverbial wheels unstuck from the sand. What effect would there be with only one panel deployed? Does the fact that it has been running for 27 days and the battery is nearly full indicate that the panels are in fact deployed? What can it do on reduced power?

    16. Creator Robert Craig Scharp on March 30, 2014

      When will we be able to follow it on Satellite Safari ?

    17. Creator Paul Giralt on March 30, 2014

      This is fantastic news! Congratulations to the team for the great accomplishment.