Around-the-World #1 (ATW-1) Project Helios David (Alex) W. has been flying weather balloons with his father Tim for years. This past November, Alex made a friendly wager with his friend, that Alex could send a balloon around the world before their upcoming high school graduation.  Alex's wagerAlex code named his first attempt of his Project Helios, Around-The-World #1 (ATW-1) NSL-78 was a brief test of this flight's hardware, a LightAPRS-W tracker. This is a solar-powered computer, GPS, and two radio transmitters -- frequency adjusting 2m APRS, and long-range 20m WSPR. After NSL-78, the hardware was rebuilt and attached to a specially constructed, superpressure "pico" balloon. A small amount of H2 was added to achieve just a few grams of free lift. The system was launched from Cardinal Gibbons High School on the afternoon of January 29, 2020.  Alex prepping for launch from Cardinal Gibbons High SchoolPowered exclusively by horizontally mounted solar panels, this balloon would only transmit from mid-morning to mid-afternoon. A super capacitor buffered the power load for the LightAPRS-W board which would wake-up, gather GPS data, and then transmit tracking data on a specific schedule. At specified times, the tracker would send out 20m WSPR packets. These took considerable time to transmit and only contained basic information -- namely transmitted power and a 4-character Maidenhead Grid Square coordinate. This gave the flight's location within 1° latitude by 2° longitude (70 mile x 100 mile rectangle). In between WSPR packets, the transmitter would also send APRS packets. APRS telemetry provided exact location, altitude, solar voltage, board temperature, speed, heading, and GPS coverage. Different countries use different APRS frequencies in the 2m band, and a few countries prohibit it entirely. The computer had to figure out, from its GPS location, what APRS frequency to use, if any. From January 29th through February 8th, we tracked the payload daily as it made its way successfully around the world! Flight notes  Day 1 Initial flight projection Day 2 over the Atlantic via WSPR Day 3 APRS data shows nearing Ireland Day 4 Over Hungary and Romainia Day 5 APRS data over Turkey Note the strong winds across Middle East and China Day 6 Plotting WSPR locations over Afghanistan Day 7 Daylight over China APRS telemetry still looking good Day 8 Morning wake-up off the coast of Japan Day 9 Pacific between Hawaii and Dutch Harbor Day 10 Approaching North America Prediction for the following three days Day 11 Wyoming and Colorado Will it miss Colorado storms? Day 12 Completed first trip around the world ! 12 Feb, 2020: Flight has since continued on to England and then down to Morocco and over to Egypt. 17 Feb, 2020: Flight has come ashore in North America again. Currently floating over Mexico 29 Feb, 2020: Flight completed third full trip around the world. 11 Mar, 2020: Flight completed fourth trip around the world. 29 Mar, 2020: Flight completed fifth trip around the world. 10 Apr, 2020: It's been 10 days since last confirmed contact.  The last APRS packet was received as the balloon past the Canary Islands approaching the coast of Morocco midday on 31 Mar. 2020-03-31 11:27:14 Position: 30°11.70' N 10°24.24' W WSPR packets continued until sunset as it made landfall and flew over Marrakesh, Morocco. No further APRS packets have been received at this time. Assuming flight consistent with the previous trips, the balloon should have followed its usual patch across the Mid-east, China, and over the Pacific.  But a few days later, a single WSPR packet was received in an unusual location! 2020-04-03 14:50 Grid square: QP58 This location is in northern Siberia (roughly 68.5N, 151.0E). Which seams way off of the expected path. Only a single packet was received. Was there some sort of GPS or data corruption that led to this strange packet? Or did the balloon really drift towards the north pole? If the balloon did travel far north, then it makes sense that we haven't heard from it. The sun angle would be too low in the sky illuminate the solar panels sufficiently.  ·Payload:
This all may be overkill but we did a test flight (NSL-78) with designs shown elsewhere and at 12km while the balloon was entering the jet-stream the panels and the antennas got ripped off. It was a worst-case scenario in that we had an ascent rate of 6+m/s. We had a backup TX that allowed us to recover the payload. There was nothing left but the LightARPS-w on a string. Fill info:
Three things currently concern me.
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