Citizen Scientist Spots New Kreutz Sungrazer in CCOR-1 as Weather Satellite Reshapes Comet Science

Early Sunday morning, volunteer comet hunter Jiangao Ruan filed a candidate report at 9:04 a.m. UTC flagging a new Kreutz-group sungrazer in data captured by CCOR-1, the solar coronagraph aboard NOAA's GOES-19 weather satellite. Fellow citizen scientist Zesheng Yang co-signed the submission the same morning. The candidate now awaits confirmation from staff at the Naval Research Laboratory — the latest in a sequence that has quietly made a weather-monitoring coronagraph into the world's most productive sungrazing-comet finder, staffed almost entirely by people who do this for free.

That outcome was not planned. CCOR-1 was designed and funded as an operational space-weather tool: its job is to image the Sun's outer atmosphere and catch coronal mass ejections before they slam into Earth's magnetosphere. The fact that it can also detect faint comets on suicide trajectories toward the solar surface is, from NOAA's perspective, a side effect — one that Karl Battams and his team at NRL's Sungrazer Project have turned into an ongoing, real-time discovery pipeline. What this shows, beyond the specific discovery on November 1, 2026, is that the moment you build an operational space coronagraph and give volunteers access to the data, you do not just create a science instrument. You create a comet-hunting network that runs 24 hours a day, seven days a week, without a dedicated science budget.

What CCOR-1 Was Designed to Do — and What It Is Actually Doing

The Compact Coronagraph-1, built by NRL and launched aboard GOES-19 (formerly GOES-U) on June 25, 2024, is primarily a space-weather monitoring asset. It monitors the Sun's outer corona across a field of view extending from roughly 3.7 to 18.7 solar radii from Sun center — an annular window that CMEs must cross on their way to Earth. The instrument uses an external occulter to block the solar disk, creating an artificial eclipse that makes the far-dimmer corona visible. The detector is a 2,048 × 1,920 pixel active pixel sensor imaging in white light across a wavelength range of 450 to 750 nm, with a spatial resolution of approximately 33 arcseconds per pixel. Under nominal operations, CCOR-1 acquires one image every 15 minutes.

None of that description contains the word "comet." And yet by July 11, 2025 — roughly nine months after CCOR-1 began science operations — the Sungrazer Project had already logged more than 70 confirmed comets from its data. By November 2026, that number is considerably larger. The reason has everything to do with orbital mechanics and almost nothing to do with CCOR-1's design intent.

How a Weather Coronagraph Catches Comets It Was Never Meant to Find

A Kreutz sungrazer follows a steeply inclined orbit that carries it through the inner solar system on an almost radial trajectory toward the Sun. At perihelion — the closest approach — these comets pass within 50,000 kilometers (31,070 miles) of the solar surface, well inside the orbit of Mercury and well inside CCOR-1's inner field-of-view boundary. The corona they have to cross on the way in sits precisely inside the annular window CCOR-1 images continuously.

This is the mechanism: a Kreutz sungrazer inbound toward perihelion travels through the 3.7-to-18.7-solar-radii window that CCOR-1 is already watching. To the instrument, it appears as a faint, slowly brightening streak crossing the outer corona over the course of hours to days. The sungrazer is not the target — it is a visitor to a window the coronagraph was watching for other reasons.

The catch is detection. CCOR-1 acquires one image every 15 minutes, and a fast-moving comet near perihelion can travel several degrees of arc in that time. A faint sungrazer may appear in only two or three consecutive frames before it either passes out of the FOV or disintegrates. Automated algorithms, tuned for the slower, larger-scale motion signatures of CMEs, miss many of these brief transits. Human pattern recognition — specifically the pattern recognition of a volunteer who has spent months reviewing CCOR-1 images — is what catches them.

That is the citizen science layer, and it is not incidental to CCOR-1's comet productivity. It is the reason CCOR-1 is productive at all.

Jiangao Ruan and the Anatomy of a Discovery

The Sungrazer Project's submission workflow requires two layers of human validation before NRL scientists review a candidate. A volunteer submits a report identifying the candidate's location in a CCOR-1 frame — in Ruan's November 1 report, the object was flagged in the upper-left region of the coronagraph's field — and then a second registered volunteer must endorse the submission before it enters the NRL review queue. On Sunday, Zesheng Yang served as the endorser. NRL staff then assess the endorsed report, check adjacent frames, and determine whether to log it as a confirmed discovery.

Jiangao Ruan is, by any measure, the most prolific contributor in the CCOR-1 era. A review of the Sungrazer Project's 2026 comet table shows his name appearing dozens of times from January through October — a sustained pace of discovery that reflects both the volume of CCOR-1 data available and the depth of pattern recognition that comes from months of dedicated review. No automated system and no single NRL scientist can match the effective throughput of a global volunteer network scanning the same data around the clock from different time zones.

What Are Kreutz Sungrazers, and Why Do So Many Disintegrate?

The Kreutz family is what remains of a much larger fragmented comet — or possibly a sequence of progressively smaller fragments — that broke apart over a timeline stretching back roughly 2,000 years. Named after German astronomer Heinrich Kreutz, who established the family's shared orbital identity in the late nineteenth century, these objects share a characteristic perihelion argument and orbital inclination that places them on nearly identical paths to the same fatal encounter with the Sun.

Approximately 83 percent of SOHO sungrazers found by SOHO's LASCO instrument are Kreutz-group members. Most of the ones CCOR-1 detects are fragments too small and volatile to survive perihelion — they brighten as cometary activity increases with proximity to the Sun, then sublimate completely in the final hours of approach. What CCOR-1 sees is the death of a comet: the last brightening before the object ceases to exist.

Occasionally, a Kreutz member is large enough to survive. The Great Comet of 1843, the Great Comet of 1882, and Ikeya–Seki in 1965 were all Kreutz-group members that survived perihelion and became spectacular naked-eye objects. The small sungrazers CCOR-1 detects routinely — the ones Jiangao Ruan flags — are the far end of the same size distribution. They are scientifically valuable precisely because tracking the background fragmentation rate of the Kreutz family over years and decades tells researchers something about the parent body's structure and decay timeline.

CCOR-1, CCOR-2, and the Two-Coronagraph Era

A second NRL-built compact coronagraph, CCOR-2, is now operating at the Sun–Earth Lagrange 1 point aboard NOAA's Solar Wind Follow-On (SWFO-L1) spacecraft. SWFO-L1 launched on September 24, 2025, reached L1 orbit in January 2026, and CCOR-2's data went public in June 2026. The first Kreutz sungrazer discovered in CCOR-2 data came just twelve days later, on June 29, 2026 — spotted by citizen scientist Michael Stark.

CCOR-1 and CCOR-2 observe the Sun from different vantage points: CCOR-1 from geostationary orbit, CCOR-2 from L1. This means their FOV orientations differ, and comets that appear in one instrument's frame do not always appear in the other's. Two coronagraphs running simultaneously give the Sungrazer Project team — and the volunteer network that feeds it — overlapping data coverage and the beginnings of a stereoscopic solar coronagraph capability.

The most extensively observed Kreutz sungrazer in CCOR-1's history to date was C/2026 A1 (MAPS), discovered January 13, 2026. The comet was tracked continuously as it approached, brightened, and ultimately disintegrated near perihelion April 2026. It produced some of the highest-resolution inbound tracking data in Kreutz sungrazer history and demonstrated the full diagnostic value of CCOR-1's wide-area detector for extended comet monitoring.

2026's Pace and What Sunday's Report Adds

The year 2026 has been among the most active on record for Kreutz sungrazer detections in CCOR-1 data. The coronagraph comets table at sungrazer.nrl.navy.mil documents discoveries across every month of the year, with Jiangao Ruan accounting for a substantial share. Sunday's submission, if confirmed, adds to that count.

The Sungrazer Project reached a wider milestone on March 25, 2024, when the 5,000th comet was discovered in data from SOHO's LASCO instrument — a program that has run continuously since 1995 and represents the largest single database of solar comet discoveries in history. CCOR-1's rapid accumulation of discoveries since late 2024 suggests the total across both instruments will continue growing substantially.

NRL had not yet confirmed Sunday's Kreutz candidate as of this writing. Confirmation typically takes days, during which Sungrazer Project staff examine adjacent frames, check orbital consistency with the Kreutz family's known parameters, and rule out image artifacts. If confirmed, Sunday's object will enter the Sungrazer Project's official catalog and be assigned a formal designation.

Can You Participate?

The Sungrazer Project accepts volunteer reports from any registered participant at sungrazer.nrl.navy.mil. Real-time CCOR-1 imagery is publicly available through NOAA's Space Weather Data and Information (SWDI) portal. No prior astronomy experience is required to browse the images, though contributors note that calibrating the eye to distinguish comet candidates from artifacts takes time and repeated exposure to the data.

Jiangao Ruan's November 1 report is the result of exactly that kind of accumulated expertise — applied to a geostationary weather satellite's data in the early morning hours, on a Sunday, because the comets do not take days off and neither does he.

Frequently Asked Questions

What is a Kreutz sungrazer, and why do most of them disappear?

A Kreutz sungrazer is a member of a comet family that shares nearly identical orbital parameters, all of them tracing back to a single large comet that fragmented thousands of years ago. The family is named after German astronomer Heinrich Kreutz, who established the orbital relationship in the nineteenth century. At perihelion — their closest approach to the Sun — Kreutz sungrazers pass within roughly 50,000 kilometers (31,070 miles) of the solar surface. Most of the small ones CCOR-1 detects are too fragile and volatile to survive that encounter: intense heat and tidal forces sublimate them completely in the final hours of approach. About 83 percent of SOHO-found sungrazers are Kreutz family members. Occasionally, a larger Kreutz member survives perihelion and becomes a spectacular naked-eye comet — the Great Comet of 1882 and Ikeya–Seki comet in 1965 were both Kreutz members.

How does CCOR-1 detect comets when it was built to watch for solar storms?

CCOR-1 uses an external occulter to block the solar disk and image the much dimmer corona — the Sun's outer atmosphere — in search of coronal mass ejections heading toward Earth. That same annular field of view, spanning from roughly 3.7 to 18.7 solar radii from Sun center, is precisely the zone that inbound Kreutz sungrazers must cross on their way to perihelion. To CCOR-1, a comet is just another object transiting its coronagraph field. The instrument's 15-minute image cadence means fast-moving sungrazers may appear in only a handful of consecutive frames — human volunteers, scanning continuously, catch them at a rate automated algorithms cannot match.

What is the Sungrazer Project, and who runs it?

The Sungrazer Project is a citizen science program administered by Karl Battams and colleagues at the Naval Research Laboratory in Washington, D.C. It accepts comet candidate reports from registered public volunteers who review data from CCOR-1, CCOR-2, and SOHO's LASCO instrument. Submitted reports require a second volunteer endorser before they reach NRL staff for review, providing a two-layer quality filter. The project has accumulated more than 5,000 SOHO comets across the SOHO-era data since 1995, with CCOR-1 adding more than 70 confirmed finds in its first nine months of operation alone.

Can an ordinary person discover a comet right now?

Yes. The Sungrazer Project accepts new volunteer registrations, and real-time CCOR-1 imagery is publicly available through NOAA's Space Weather Data portal. No specialized equipment is required — only a computer, an internet connection, and the patience to learn what a real comet candidate looks like versus a common image artifact. Most contributors describe a learning curve of several weeks of regular review before confidence in recognizing comet signatures develops. Jiangao Ruan's November 1 discovery is the product of exactly that accumulated eye — applied to live federal space-weather data that any member of the public can access today.