Pico Balloon Serial #8 and #9
August 19, 2025
Location & Direction
The balloon has shifted from west to east and south to north over the past three days.
Aug 15: Position in the CL23–CL33 grids (west-central Mexico).
Aug 16: Moving eastward into the CL52–CL63 grids.
Aug 17: Entered the DM00–DM23 grids, tracking northeast toward the U.S. border region.
Overall Path: A steady North/Easterly track, consistent with summertime subtropical winds.
Altitude & Stability
Altitude has remained consistently between 12,580–12,740 meters (≈41,270–41,800 ft).
Variations are minor (±20 m), indicating stable flight conditions.
No significant altitude oscillations or descent patterns have been detected.
Speed
Aug 15: Very light winds, speeds of 0–12 mph.
Aug 16: Picked up to 20–30 mph.
Aug 17: Increased further, averaging 40–60 mph, confirming entry into a faster eastward flow.
Solar Power & Voltage
Voltage steady at 4.3–4.65 V, indicating the solar/battery system is working flawlessly.
No evidence of power drops at night or during early morning passes.
The solar array is functioning normally with no anomalies.
Temperature & System Health
Ambient readings range -10°C to -17°C at altitude.
No unusual thermal shifts that would suggest envelope strain.
Telemetry appears clean, with no corrupted or missing data bursts.
Overall Condition
Stable altitude, solid power, consistent data.
Balloon is eastbound with a northerly component, currently traveling faster than earlier in the week.
All systems remain nominal as it completes its 19th day in flight.
📍 Current Status (as of Aug 17, 16:54 UTC)
Grid: DM23
Altitude: ~12,640 m (41,470 ft)
Speed: ~55 mph, moving east/northeast
Voltage: 4.15 V
Condition: Stable, fully operational
Serial #9, a high-altitude pico balloon, appears to have been brought down by Hurricane Erin. Its final transmission was logged on August 15.
Flight data indicates the balloon’s altitude began fluctuating wildly during its last hours, suggesting it encountered unstable atmospheric conditions. Although the balloon was positioned some distance from the storm’s eye, one of Erin’s outer bands likely reached far enough to disrupt its flight.
It remains unclear whether the balloon was directly downed by the storm or if a failure in the envelope contributed to its loss. Without recovery of the balloon or additional telemetry, the exact cause cannot be confirmed.
Updated August 14, 2025
Pico Balloon Serial #8: Launch- Harlingen, Texas (July 30, 2025 )
Current Area: Central Pacific Ocean, south of Hawaii, near 23°N and ~130°W.
Pattern: The balloon is now traveling in slow, looping circles, caught in the trade wind circulation.
Altitude: Very stable around 41,500 ft (12.65 km), ideal for long-duration flights.
Speed: Generally 18–27 mph, depending on wind currents.
Movement: Over the past day, the latitude/longitude changes indicate it’s drifting within a small area, confirming it’s looping rather than heading in a straight path.
Environmental & System Health
Voltage: Around 4.4–4.8 V, consistent for solar-powered electronics — suggests good sunlight and battery performance.
Temperature: Between -15°F (early morning, higher altitude) and ~83°F (daytime at altitude). These swings match diurnal heating/cooling at that height.
TX Power: Steady at 13 dBm, no indication of transmitter issues.
Reception: Max RX distances reported over 7,100 miles, meaning ground stations thousands of miles away are still decoding signals clearly.
Signal Quality (SNR): Peaks up to +9 dB, but often negative when received at extreme distances — still entirely usable.
Recent Flight Behavior
Between Aug 12–13, balloon showed:
Stable altitude with only ±130 ft variation.
Speeds mostly 21–25 mph, slowing to 18 mph at times.
Small position shifts consistent with a circular path.
Voltage drops slightly before sunrise, then peaks midday.
No evidence of rapid altitude loss or erratic movement, so the envelope is likely intact and holding helium well.
Simple Conclusion
Pico Balloon #8 is healthy, stable, and trapped in a Pacific trade wind loop.
It’s maintaining altitude, power, and transmission strength, so barring envelope failure or bad weather, it could keep circling in this region for weeks or even months. This is a classic long-duration flight profile after a transoceanic leg — essentially a “marathon in place.”
Pico Balloon Serial #9: Launch- Harlingen, Texas (Aug 10, 2025 )
Altitude: Generally between ~10,840 m and ~11,140 m (35,500–36,500 ft). Balloon stayed mostly in a stable band around 11,000 m. Small oscillations ±100–200 m.
Vertical Speed: Mostly small climbs/descents, ±20–40 ft/min; occasional sharper changes (e.g., 644 m/min, likely a burst or rapid ascent phase).
Temperature: Around -30 °C to -15 °C at cruise altitude. Cooler at higher altitudes as expected.
Voltage: Mostly stable 3.7–4.0 V, slight drops over time, as would occur with a solar powered balloon.
Speed: Horizontal GPS speed ~20–50 mph (32–80 kph), mostly around 25–45 mph.
Distance: The balloon moved steadily, covering several hundred kilometers over the two-day span.
It is now over the Atlantic , Northwest of Bermuda. The winds show it should soon start moving back north into Canada. By the current wind patterns it looks to be making several "S" turns as it crosses the Atlantic to the European coastline.
— K5RGV Rio Amateur Radio Club
Updated August 11, 2025
Serial #9: Yesterday, Rio Amateur Radio Club member Tom, WT5TX, launched a second Pico Balloon from his home around 7:00 AM. This marks the first time two balloons have been aloft simultaneously since he began building and launching them. This balloon is Pico Serial #9. Unlike its predecessor, it has been slowly drifting northeast. At the last report, it remained within 150 miles of the launch site here in Harlingen, Texas, having started transmissions at 8:48 AM.
The balloon steadily gained altitude throughout the morning, eventually reaching approximately 35,000 to 36,000 feet (about 10,900 meters). It traveled at an average speed of 15 to 20 MPH (25 KPH) during the day.
Serial #9 passed over Raymondville heading north, then shifted to a northeasterly course. Its final report yesterday came from roughly 150 miles from Harlingen. The balloon is now well beyond South Padre Island and out over the Gulf of Mexico.
What sets this balloon apart is that it actually consists of two balloon envelopes connected at the nozzles, with the payload suspended from that junction. Additionally, this is the first balloon in the series to operate on the 20-meter band. Its dipole antenna measures just over 32 feet—ironically close to 20 meters in length. This frequency band tends to be more open than the 10 and 17 meters used by previous balloons. Tom hopes to determine if this makes a difference, and the balloon will need to prove itself over the coming days.
Serial #8: This balloon has now officially set the record for the longest flight launched by Tom (WT5TX). It lifted off on July 30, 2025, and has impressively remained aloft for 13 days. Hopefully, this longevity continues to favor the resilient balloon.
Overall, Serial #8’s journey has been both steady and insightful. From the very beginning, it took an unusual course—heading southwest into Mexico rather than east. It passed over Monterrey, then ventured out into the Pacific Ocean just south of the Gulf of California. From there, it traveled nearly due south to a point approximately 150 miles west of Puerto Vallarta.
The balloon spent the day circling in that area before making its way back into the Gulf of California, where it hovered again for another day. It then drifted just off the coast of Cabo San Lucas, lingering in that region for an additional day.
After these stops, it moved slowly in a broad arc—first south-southwest, then west—descending to around 7 degrees latitude before turning northward. Over several days, it traveled west-northwest before shifting course eastward. At the last report, it remained a couple hundred miles off Baja California, south of Ensenada, Mexico.
The upper-level winds over the Pacific appear to be swirling at the balloon’s current altitude of 41,000 to 42,000 feet. It is expected to resume transmitting around 12:20 PM today, and it will be interesting to track where it drifts during the evening hours.
Updated August 8 , 2025
Pico Balloon Serial 8 Daily Report
After a long night of silence due to its solar-only power system, Pico Balloon Serial 8 reawakened this morning as the sun’s rays reached its panels. The first signal came in at 16:44 UTC (11:44 AM Harlingen time), reporting from DJ38xa at 8.02°N, -112.04°W at an altitude of 41,270 feet.
During the overnight hours, the balloon drifted unreported across the Pacific in total darkness, as its electronics were inactive without sunlight. Based on the last known heading from yesterday and today’s first signal, the balloon has shifted direction — moving more toward the north, instead of the previous west-northwest track. This course change could be influenced by high-altitude wind pattern shifts.
It is currently about 1,550 miles southwest of Harlingen, Texas, and roughly 660 miles from the nearest landmass in Central America. Speed at last report was around 16 mph with a climb/descent rate of zero, indicating steady altitude flight.
Reception this morning was from 3,303 miles away, with a maximum signal-to-noise ratio of -8 dB, meaning its tiny signal is still reaching far-flung amateur stations with remarkable clarity.
Summary of the last 24 hours:
Direction change: Shift from WNW to NNE heading.
Distance traveled since yesterday: ~380 miles.
Current status: Stable altitude, slow drift NNE over the Pacific.
— K5RGV Rio Amateur Radio Club
Updated August 7, 2025
Pico Balloon Serial 8 — Day 8 Report
Builder: WT5TX
Launched from: Harlingen, TX
Flight Day: 8
After drifting quietly through the night, Pico Balloon Serial #8 came back to life shortly after sunrise and has been transmitting steadily throughout the day. It continues to perform well as it floats over the eastern Pacific Ocean.
As of 18:04 UTC, the balloon was located at:
Latitude: 10.40° N
Longitude: 118.38° W
Approximate distance from Harlingen, TX: 2,036 miles (3,276 km)
Direction of travel: West-Northwest (296° azimuth)
Maidenhead Grid Square: DK00tj
Flight Performance:
Altitude: 41,540 ft
Vertical speed: Stable (0 to ±7 ft/min — essentially level)
Ground speed: 21–22 mph
External temperature: -11°F
Voltage (solar): 4.80 V and holding steady under sunlight
Power source: Solar only (no onboard batteries)
Transmission Status:
Number of ground stations receiving signal: 25 (at time of report)
Maximum receive range: 3,465 miles
Best signal-to-noise ratio (SNR): -2 dB
Transmit power: ~13 dBm
Sun angle: 13°, sufficient for continued solar operation
Pico Balloon #8 continues to perform reliably with stable altitude, consistent solar voltage, and good signal reception across a wide area. With no sign of descent and strong sunlight keeping it powered, the balloon appears set for an extended flight.
— K5RGV Rio Amateur Radio Club
Updated The Evening of August 6, 2025
Pico Balloon Serial 8 — Evening Report
Last heard: 22:44 UTC (5:44 PM CDT)
Current Location: 7.73° N, 113.38° W — Grid DJ37hr
Distance from Harlingen, TX: ~1,570 miles southwest
Direction of travel: Consistently westward
After a quiet overnight period and a successful reappearance earlier today, Serial 8 maintained steady performance into the evening hours. As of the latest packet at 22:44 UTC, the balloon is cruising at an altitude of 41,400 ft, with no significant vertical movement detected. This consistent altitude suggests stable atmospheric conditions and well-regulated internal pressure.
Flight Stats
Speed: 23 mph at last update
Battery Voltage: 4.35V — slightly lower than mid-day but still healthy
Temperature: –8°F (a dip from this morning’s –6°F)
Climb Rate: 0 ft/min — stable at float
Sun Angle: 44° — nearing late afternoon light
Reception and Signal
Number of Receivers (RX): 13 at last transmission
Maximum Reception Range: 3,376 miles — impressive for WSPR reception
Signal-to-Noise Ratio (SNR): –10 dB — typical for long-range weak signal propagation
At its peak this afternoon, a total of 22 stations simultaneously received its signal. The farthest ground station during today’s run was 6,529 miles away — a testament to the efficiency of WSPR's low-power, long-distance communication protocol.
Location Insights
Latitude/Longitude: 7.73° N, 113.38° W
Distance from Harlingen, TX: ~1,570 miles
Azimuth from Harlingen: ~228° (SW direction)
Closest mainland coast: Over 800 miles northeast (likely Mexico's southern coast)
Nearest major city: Guatemala City, approx. 1,250 miles to the northeast
Technical Notes
Voltage levels have gradually decreased through the afternoon but remain in safe operating range. This is expected as solar angle drops into late afternoon.
The balloon showed occasional small vertical oscillations, likely due to solar heating/cooling and minor atmospheric waves. These ranged between –20 and +26 ft/min, all within typical float tolerance.
Temperature fluctuations across the afternoon ranged from –13°F to 10°F, indicating high-altitude thermal cycling and likely occasional cloud cover.
Flight Summary
Serial 8 is now deep into the eastern Pacific on its 8th consecutive day aloft, with no signs of distress or power failure. It continues to benefit from favorable upper-atmosphere winds, maintaining a steady west-southwest trajectory. The slow but persistent drift suggests the balloon is riding easterly tropical winds near the equator, likely part of the tropical easterly jet stream.
If conditions hold, it should remain trackable well into Day 9. We'll continue watching for the overnight power-down and hope for another successful sunrise wake-up tomorrow.
Stay tuned for tomorrow’s first signal — expected between 11:30 AM and 12:00 PM CDT if patterns continue.
— K5RGV Rio Amateur Radio Club
Pico Balloon Serial 8 – Morning Report
August 6, 2025 | First signal received at 11:44 AM CDT
After what felt like an eternity of radio silence overnight, Serial 8 finally came back to life around 11:44 AM local time. It was first picked up at grid DJ38XA, which corresponds to coordinates near 8.02° N, -112.04° W—still well over the eastern Pacific Ocean, south-southwest of the Baja Peninsula.
At first contact today:
Altitude: ~41,270 ft
Speed: 16 mph
Temperature: –6°F
Battery Voltage: 4.75V
Sun Angle: 48° (strong solar exposure)
Total Receivers: 16 ground stations picked it up during this pass, with the farthest being 3,303 miles away.
Position & Distance Details
Current Lat/Lon: 8.02° N, 112.04° W
Direction: It continued heading westward, with steady progress.
Distance from Harlingen, TX:
Approx. 1,456 miles southwest, over the Pacific Ocean.
Overnight Activity
The balloon likely lost contact after sunset yesterday due to solar power drop-off, a common occurrence for pico balloons. Based on projected trajectory and current data, it drifted west overnight across lower Central America latitudes without transmitting.
Since its last known position on August 5th, it has traveled roughly:
~215 miles west during the dark hours.
Ascent/Descent: No major altitude shifts, with cruising altitude holding steady around 41,000–41,200 ft.
System Health
Voltage: Strong recharge at 4.75V suggests full solar panel exposure.
Temperature: Warmer today (–6°F) compared to yesterday's –17°F.
GPS speed: Confirmed consistent motion (~16 mph) indicating the balloon is catching strong easterly winds at its cruising level.
Max SNR: –8 dB at the furthest receiver (typical for long-range WSPR).
Closest Landmarks
Still hundreds of miles offshore from any major coastline.
Nearest notable landmass: Southwestern Mexico, but it's over 700 miles northeast.
Nearest major city: Guatemala City is ~1,100 miles to the northeast.
Summary
On its 8th day aloft, Serial 8 continues its Pacific crossing. The balloon remains stable, with excellent system performance and a healthy voltage level. It’s now pushing deeper westward and holding a clean altitude—an encouraging sign for continued long-distance propagation and reception.
We’ll continue monitoring for its next transmission window.
— K5RGV Rio Amateur Radio Club
Pico Balloon Serial #8 – Full Flight Synopsis
Updated The Evening of August 5, 2025
Serial #8 of the Rio ARC pico balloon program continues its high-altitude adventure, gracefully drifting westward through the upper atmosphere. As of sunset, the balloon was last heard from at 11.5°N, 109.0°W—hovering above the open Pacific Ocean at 41,340 feet. That’s roughly 1,185 miles (1,907 km) southwest of Harlingen, Texas, where its journey began nearly a week ago.
Throughout the day, the balloon covered approximately 152 miles (245 km) during daylight hours. It maintained a steady cruise altitude between 40,880 and 41,340 feet, floating serenely on stratospheric winds. Ground speed peaked at around 16 mph, though for much of the day it leisurely coasted at speeds between 12–14 mph.
Temperatures aloft varied from -23°C to -2°C (-9°F to 28°F), a reminder that even in August, the stratosphere isn't exactly beach weather. Voltage held strong throughout, climbing to 4.95V during peak sun.
The balloon’s signal was heard by up to 77 ground stations simultaneously, a new daily high. The furthest receiver to detect it today was an impressive 6,160 miles (9,910 km) away, once again showing just how good WSPR can be when you give it altitude and sunshine.
Its overall heading remains south-southwest, still offshore and roughly 650 miles from the nearest landmass—Mexico’s Pacific coast near Manzanillo, though the closest major city is still Puerto Vallarta, about 730 miles northeast.
As day fades into night, Serial #8 settles in for another dark and silent stratospheric drift, systems ready for another sunrise check-in. With luck—and no nasty squalls up there—it’ll chirp back to life sometime after 10:30 AM CDT tomorrow.
Stay tuned. The little balloon that could is still going strong.
We now wait to see how far it will travel across the Pacific before night falls again.
— K5RGV Rio Amateur Radio Club
Updated The Morning of August 5, 2025
Morning Report – August 5, 2025 | Serial 8 Pico Balloon
Time First Heard:
Serial 8 was first received at 11:14 AM CDT (16:14 UTC), marking the start of its seventh day aloft.
Location at First Reception:
It was flying over the eastern Pacific near coordinates 12.23°N, 109.21°W, in grid square DK52jf, maintaining an altitude of 40,940 feet and moving westward at a gentle pace of 5 mph.
Distance Traveled Overnight:
From its last report the previous evening (approx. 14.65°N, 109.21°W), the balloon drifted about 145 miles south-southwest overnight. This puts its average nighttime speed at roughly 10 mph, consistent with gentle nocturnal stratospheric winds.
Reception Details:
Number of receiving stations: 18
Furthest receiver: A ground station recorded reception from 1,835 miles (2,956 km) away.
Receiver with best signal-to-noise ratio: 5 dB
This strong reception range is impressive, considering the balloon's tiny transmission power and the low solar angle early in the day.
Distance from Harlingen, Texas:
The balloon is now approximately 1,135 miles southwest of Harlingen, Texas, following a long westward arc since launch.
General Status on Day 7
Serial 8 remains healthy and operational. Voltage at first light measured 4.30V, slightly lower than previous mornings but still sufficient for reliable transmission. The outside temperature was a crisp -17°F, within normal expectations for its cruising altitude.
Its vertical speed remains flat — no gain or loss in altitude — suggesting stable lift and no balloon degradation. With each passing day, it's proving itself capable of long-duration Pacific travel, and today it's squarely in open ocean with no land in sight.
As daylight increases and solar input rises, we expect improved transmission strength and additional data throughout the day.
We now wait to see how far it will travel across the Pacific before night falls again.
— K5RGV Rio Amateur Radio Club
Pico Balloon Serial #8 – Full Flight Synopsis
Updated The Evening of August 4, 2025
End of Day Report — Serial 8 Pico Balloon
Today marked the sixth day aloft for Serial 8, continuing its resilient westward push across the Pacific. The day began with the balloon transmitting from a position at 16.23°N, 108.71°W, roughly 247° (west-southwest) from its launch point near Harlingen, Texas, and now more than 1,075 miles distant from that origin.
Throughout August 4, the balloon maintained a consistent cruising altitude between 40,680 and 40,940 feet. Winds at that level carried it in a generally west to west-southwest direction, with only slight oscillations in heading. Over the course of the day, it traveled approximately 410 miles, maintaining an average ground speed between 14 and 25 mph.
Temperatures in the flight corridor ranged from a low of -17°F to a high of 0°F, reflecting typical stratospheric variation with time of day and sunlight angle. Voltage levels began strong at 4.95V and gradually settled to around 4.40V as the sun angle lowered late in the day.
At one point during the day, 42 ground stations across the globe simultaneously received telemetry from the balloon — a testament to good solar exposure and strong propagation conditions. The last report received came in at 22:24 UTC (5:24 PM CDT) at 14.65°N, 109.21°W, placing the balloon over open water, approximately 525 miles west of the Baja California coastline. Its nearest major land reference is La Paz, Mexico, lying about 545 miles to the east-southeast.
Technically, the flight appears stable, with no signs of excessive altitude drift or power instability. The slow decline in voltage toward the end of the day is expected as the sun angle drops and onboard solar input decreases.
Serial 8 is now well into its transoceanic phase, having cleared continental landmass since the early hours of Day 5. It will likely spend the next 24–48 hours over open ocean. Overnight tracking will again pause until sunrise powers up the transmitter.
We await the morning signal with cautious optimism as Serial 8 heads deeper into the Pacific.
— K5RGV Rio Amateur Radio Club
Updated The Morning of August 4, 2025
Pico Balloon Serial #8 – Day 7 Report
After its sixth consecutive night aloft, Pico Balloon Serial #8 reported in from Grid DK56pf at 11:14 AM local time, cruising at 40,682 feet above the Pacific and about 1,200 miles west of Harlingen, Texas. Overnight, it covered approximately 333 miles, averaging 18.5 mph as it continued its steady westward drift.
Conditions at altitude were brisk, with temperatures around -4°F. The balloon moved along at 25 mph and maintained a healthy 4.40 volts from its solar panels. A total of 42 stations picked up its signal, a reliable showing for its seventh morning check-in.
— K5RGV Rio Amateur Radio Club
Pico Balloon Serial #8 – Full Flight Synopsis
Updated The Evening of August 3, 2025
Pico Balloon Serial #8 – End of Day Report
After its sixth consecutive night aloft, Pico Balloon Serial #8 reported in from Grid DK56pf at 11:14 AM local time, cruising at 40,682 feet above the Pacific and about 1,200 miles west of Harlingen, Texas. Overnight, it covered approximately 333 miles, averaging 18.5 mph as it continued its steady westward drift.
Conditions at altitude were brisk, with temperatures around -4°F. The balloon moved along at 25 mph and maintained a healthy 4.40 volts from its solar panels. A total of 42 stations picked up its signal, a reliable showing for its seventh morning check-in.
As the sun now sets on Day 7, the balloon slips back into radio silence, riding the night winds toward tomorrow’s unknown. If all goes well, we’ll hear from it again when the sun hits its panels.Day 6 is in the books, and Pico Balloon Serial #8 has officially slipped into another night flight—its sixth straight evening drifting above the world, whispering telemetry by sunlight, and now gliding silently into the darkness once more.
Its last transmission came in shortly after 5:00 PM local time, just as the solar panels began to lose their grip on the sun. It had made good time today, crossing out over the Baja Peninsula and heading deep into the eastern Pacific Ocean. That puts it roughly 870 miles southwest of Harlingen, Texas, cruising at over 40,700 feet.
Let’s pause here to appreciate just what’s doing all this heavy lifting.
The payload weighs 23 grams—about the same as four U.S. quarters.
It includes a full dipole antenna, a GPS module, a WSPR transmitter, and just enough solar power to hit 4.95 volts when the sun’s shining.
The balloon itself weighs in at 70 grams, comparable to a C-cell battery.
All told, we’re talking about a setup that weighs less than a slice of bread—yet it’s logging thousands of miles from the edge of space and being heard around the world.
Final Readings Before Sunset (August 3):
Last confirmed position: Grid DL42vm
Altitude: 40,755 feet
Speed: 12 mph
Voltage (last): 4.65 V
Temperature: -7°F
Ground stations listening: 37
Last transmission: Just after 5:00 PM (local time)
Today’s performance was picture-perfect. Voltage dipped slightly in the evening, which is normal as the sun moves west and power generation slows. The altitude stayed rock steady throughout the day, and dozens of stations were still receiving its signal right up until the lights went out.
Now it’s all eyes on the morning sky.
Will it rise again with the sun?
Will the panels wake back up and shout a cheerful “I’m alive!” back to Earth?
We’ll know tomorrow.
Until then, Pico Balloon Serial #8 floats alone in the dark—still weightless, still silent, and still on one of the most efficient and elegant journeys ever launched with pocket change and a whole lot of optimism.
— K5RGV Rio Amateur Radio Club
Updated The Morning of August 3, 2025
Pico Balloon Serial #8: Mid-Morning Check-In from the Edge of the Pacific
As of 11:24 AM (local time) on August 3, Pico Balloon Serial #8 was still sailing high above the Earth, reporting in from grid DL42vm, just off the coast of Baja California. It’s riding the skies at an impressive 40,755 feet, roughly the same altitude as cross-country airliners—minus the beverage cart.
Speed & Steady Progress
Still chugging along at 12 miles per hour, this little floater isn’t built for speed—it’s built for distance. And every hour, it adds a few more miles to its journey, just cruising west with no rush and no complaints.
Power Report
The balloon’s voltage dipped slightly to 4.65 volts, down from 4.80 volts just 20 minutes earlier—likely due to a slight change in sun angle or light cloud cover. Still, plenty of juice to keep transmitting, with 37 ground stations listening in. Not bad for something drifting silently over the ocean.
Brrr Forecast
Up where the air gets thin, it’s a frosty -7 degrees Fahrenheit—definitely not hoodie weather. But Serial #8 continues to glide through it like it was born for this.
Five Nights Strong
As of this morning, the balloon has now survived five full nights in the upper atmosphere, and it’s working into its sixth day. It hasn’t missed a beat, hasn’t dropped out, and shows no signs of slowing down.
Still Westbound
Continuing its graceful journey out over the Pacific, it’s heading further from Texas with every passing hour. It’s not fast—but it’s relentless.
— K5RGV Rio Amateur Radio Club
Updated The Evening of August 2, 2025
Pico Balloon Serial #8: The High-Flying Texan Still Going Strong (and Cold)
Launched by Tom (WT5TX) of the K5RGV Rio Amateur Radio Club, Pico Balloon Serial #8 took off from Harlingen, Texas on July 30, 2025. What began as a balloon about the size of a beach ball has become a high-altitude traveler with surprising endurance and personality.
Altitude? Consistent. Temperature? Not So Much.
From 17:00 to 22:54 UTC on August 2, the balloon floated between 40,680 and 40,940 feet, cruising above the Pacific west of Baja California. Temperatures ranged from -15°F to -2°F — pretty chilly for anything that isn’t a popsicle.
Solar Power Superstar
The onboard electronics peaked at 4.95V while the sun was high. It transmitted every 10 minutes during daylight, sipping power like a champion. Voltage started to dip when the sun angle dropped below 45°, proving it prefers high noon like a true Texan.
Signal, Speed & Style
With a speed of around 7–12 mph, it’s not winning races, but it is winning hearts — broadcasting with signal-to-noise ratios up to 12 dBm. As of August 2 at 22:54 UTC, it was cruising in grid DL54xf (about 24.23°N, -108.04°W) near the west coast of Mexico.
Where Is It Now?
After logging over 2,400 miles, Serial #8 continues to glide, transmitting only in daylight and staying silent at night to conserve energy. Not bad for a balloon that weighs less than your average Twinkie.
Tiny Package, Big Presence
Fueled by sunlight and determination, this tracker continues reporting back from the stratosphere, outlasting commercial airliners and ignoring frigid winds with style.
Final Thoughts: The Little Balloon That Could (And Still Does)
Thanks to the creative work of Tom (WT5TX) and support from the K5RGV Rio Amateur Radio Club, Pico Balloon Serial #8 is proving how far a little helium, solar power, and amateur radio spirit can go. It's still transmitting. Still soaring. Still making the Rio Grande Valley proud.
— K5RGV Rio Amateur Radio Club
Updated August 2, 2025
"The High Life of Pico Balloon Serial #8: A Stratospheric Saga"
In the quiet afternoon of July 30, 2025, somewhere just outside Harlingen, Texas, a small but determined pico balloon—known officially (and somewhat bureaucratically) as Pico Balloon Serial #8—shook off the shackles of Earth, flapped its solar-powered wings (figuratively), and began its journey skyward with the grace of a caffeinated goose.
This wasn’t just any balloon. It was the handiwork of Tom (WT5TX), a member of the K5RGV Rio Amateur Radio Club, whose careful soldering, clever design, and firm belief in “why not?” gave birth to this high-altitude wanderer. Tom didn’t just launch a balloon—he launched a dream (wrapped in Mylar and lifted by helium).
It started humbly enough, at a breathless altitude of 2,760 feet, still closer to mosquitoes than meteorites. But within two hours, Serial #8 climbed to an impressive cruising height of over 40,000 feet, which is where it decided to settle. Why? Because that’s where the cool balloons hang out. Literally—it was 90°F on the ground, but up there it was a frosty -4°F to -11°F. A floating popsicle with a solar panel.
Cruising Altitude and High-Class Views
From July 31 through August 2, Serial #8 held a steady altitude between 39,000 and 41,000 feet, like it had autopilot and altitude loyalty. It floated over northern Mexico, waved politely to Durango and Sinaloa (probably not seen), then took a graceful westward turn and headed out over the Pacific Ocean.
While you might think it’d be zipping around like a jet stream junkie, Serial #8 was more of a sky-snail—gliding gently at 5 to 7 mph over open water. It's not in a rush. It’s a balloon. It floats. Like enlightenment.
Solar-Powered Superstar
Now, Serial #8 is no night owl. It's a strictly daylight creature, transmitting only when its solar panels have enough juice to send out position, altitude, speed, temperature, and the occasional "wish you were here" in digital form.
* Transmission Power: Peaked at a mighty +12 dBm, with some weaker squeaks at -6 dBm
* Battery Voltage: Mostly between 4.65V and 4.95V—think of it as a caffeine drip for the electronics
* Best Signal Times: Late morning to early afternoon, when sun angles hit that sweet spot between 45° and 80°
* Radio Reception: Heard up to 8,319 miles away. We can neither confirm nor deny alien reception.
At night? Silence. Serial #8 goes full Garfield mode—no sunlight, no transmissions.
It’s Cold Up Here, Bro
Altitude comes at a price: frigid temperatures. Once it hit the stratosphere, the balloon was floating in air as cold as -11°F, with occasional balmy spells around 0°F. Yet it thrived. Mostly because microcontrollers don’t complain about frostbite.
The World According to Serial #8
By August 2, 15:54 UTC, Serial #8 had logged approximately 2,396 miles—and was hovering around 23.50°N, -109.00°W, in grid DL53, southwest of Baja California. That’s not vacationing in Cabo; that’s floating alone in the mid-Pacific like a philosophical beach ball.
Its altitude wasn’t recorded in the last transmission, but the prior one clocked in at 40,680 feet, so we assume it’s still up there, doing a high-altitude backstroke.
The Balloon Diaries (Data as Drama)
* Fastest Pace: 30 mph (on day one, fresh out the gate)
* Slowest Pace: 0 mph (once, on Aug 1—maybe taking a siesta)
* Best Voltage: 4.95V (basically running a clean power grid)
* Temperature Swings: From a warm-blooded +61°F on ascent to an icicle-worthy -11°F
* Most Listeners in One Burst: 69 stations—Serial #8 has fans!
* Most Distant Reception: Over 8,000 miles—eat your heart out, ham radio.
Where To Next?
If prevailing winds allow, Serial #8 could:
* Drift further west, entering even more remote Pacific airspace
* Catch a polar vortex, if it feels adventurous
* Circumnavigate Earth, if it's feeling extra spicy and the helium holds up
Realistically, it’ll continue coasting slowly until the envelope degrades or the sun forgets to shine for a day.
Closing Thoughts
What started as a hobby project by a dedicated ham in South Texas became an elegant, solar-powered dance across the sky. Pico Balloon Serial #8, built and launched by Tom (WT5TX) under the banner of the K5RGV Rio Amateur Radio Club, floats on—slow, steady, and freezing cold—but with a signal strong enough to whisper across continents.
May it continue its noble float, basking in the sun, whispering telemetry to the world, and reminding us all that even the tiniest balloon can aim for the stratosphere.
— K5RGV Rio Amateur Radio Club