GOES-17, A Fighter Among Weather Satellites, Faces Yet Another Health Hiccup

The weather satellite that monitors the Pacific Ocean and western North America went into safety mode and stopped transmitting data early Thursday morning. There's no public word on what's troubling GOES-17, which is also called GOES-West, aside from a statement that engineers are "aggressively troubleshooting" the issue and working toward a fix.

The satellite is the 17th member of the Geostationary Operational Environmental Satellite (GOES) program, and it serves alongside its twin GOES-16, which monitors the Atlantic Ocean and the eastern side of the Americas as GOES-East.

GOES-West and GOES-East work in tandem to provide breathtaking images that are a tremendous boon to meteorologists monitoring the skies above and what lies beyond the horizon.

We can get high-resolution images of a small area every 30 seconds, national images every 5 minutes, and full-hemisphere images every 10 minutes. The resolution and turnaround time are a vast improvement over past GOES generations.

GOES-West's view of North America on July 21, 2021. (NOAA)

GOES-17 is the little satellite that could. The spacecraft launched in March 2018 with a major flaw that threatened its existence before it even had a chance to shine.

We get our satellite imagery from a device called the Advanced Baseline Imager (ABI). This sensor uses visible and infrared radiation to create the vibrant images we see online and on television every day.

A geostationary satellite orbits at the exact same speed at which Earth rotates, giving the satellite the same view of Earth for its entire service life.

This fixed orbit exposes the ABI to hot sunshine when it's nighttime here in North America. While it's very cold in space, a hard-working mechanical device basking in direct sunshine gets dangerously hot and it needs a robust cooling system in order to function properly.

After reaching orbit, engineers discovered that one of the cooling pipes that served the ABI was clogged, preventing the sensor from cooling off effectively during times of peak heating.

An example of the interference in infrared satellite imagery caused by excess heat given off by the ABI. (NOAA)

This flaw causes the sensor to grow so hot that it gives off radiation that matches the wavelengths of some infrared and water vapor products, significantly degrading many of the products generated by the ABI during moments of peak warmth.

Engineers had to develop some significant workarounds to get the satellite working in the face of this unfixable flaw. There are still certain times of the day and year where the satellite's performance is degraded.

This isn't the first time GOES-17 unexpectedly shut down. A software glitch in August 2019 knocked the ABI offline for about 11 hours. Engineers solved the problem with the old "turn it off and on again" trick.

NOAA announced last month that they plan to launch GOES-18 in December and designate the new satellite as GOES-West in early 2022, sending GOES-17 into a well-earned retirement.

Fortunately, the previous generation of satellites stands by in case any of the operational satellites feel under the weather.

If GOES-17 requires prolonged downtime between now and the launch of the next satellite, the satellite that previously served as GOES-West (GOES-15) can be swapped in as an emergency substitute.

While the image resolution and speed at which we get new images would fall a bit from what we've grown used to, the substitution would still fill the gap and help meteorologists perform their jobs effectively.

[Top Image: The last satellite image transmitted by GOES-17 before it went down last night, via NOAA]

---

You can follow me on Twitter or send me an email.

Please consider subscribing to my Patreon. Your support helps me write engaging, hype-free weather coverage—no fretting over ad revenue, no chasing viral clicks. Just the weather.