Deep-Space Observatory · Cerro Miranda, Chile · Est. 1987
HELIOS is a sky-survey institute. Four instruments on one ridge in the Atacama photograph, time, and measure the entire southern sky, again and again, until the universe has nowhere left to hide a change.
Four instruments share one ridge and one clock. Between dusk and dawn they run unattended. The mountain observes; the institute listens.
The flagship. A 3.2-gigapixel camera on the 8.4-metre reflector photographs the full southern hemisphere every 72 hours, to magnitude 24.6. Anything that moved, brightened, or vanished since the last pass raises an alert within 41 seconds.
Nine identical 0.4-metre telescopes stare at 240 000 nearby dwarf stars and wait for the 0.01 % dip that means a world crossed its sun. Three hundred and twelve planets confirmed; eleven of them small, rocky, and temperate.
Thirty-nine years of plates and pixels, reduced to one question: where is everything actually going? Parallax measures proper motions to eight micro-arcseconds a year: the width of a coin on the Moon, seen from Chile.
To know our own star’s temper, watch its twins. Corona-B takes nightly spectra of 1 150 Sun-like stars, tracing their spot cycles and flares across decades. A weather report for suns, including the one we live beside.
Conditions and targets over Cerro Miranda, refreshed from the summit weather mast and the scheduler queue. —
| Object | RA / Dec | Alt | Mag | Program |
|---|---|---|---|---|
| ω Centauri | 13:26:47 −47:28 | 72° | 3.9 | PARALLAX |
| SN 2026gz | 11:18:16 −32:48 | 54° | 17.2 | MERIDIAN |
| HD 118203 | 13:34:02 +53:43 | 18° | 8.1 | CORONA-B |
| TOI-4562 b | 07:29:36 −68:04 | 41° | 12.1 | TRANSIT-9 |
| NGC 5139 field | 13:27:00 −47:30 | 71° | — | MERIDIAN |
| Prox Cen flare watch | 14:29:43 −62:40 | 63° | 11.1 | CORONA-B |
ALTITUDES UPDATE LIVE · QUEUE DEPTH 214 TARGETS
EACH TILE = ONE 30 s EXPOSURE · 0/642 COMPLETE
What thirty-nine years of patience buys. Selected results from the survey archive, peer-reviewed and public.
In 2021 Meridian caught SN 2021qv lensed by a foreground cluster. Our models said its light would arrive again, by a longer gravitational path, in March 2026. It did, eleven days early, pinning the cluster’s dark-matter mass to 4 %.
READ THE PAPER →HEL 88712, a solar twin 41 light-years away, has not flared once in nineteen years of Corona-B spectra: the flattest activity record ever measured. If calm suns make habitable systems, this is where to look next.
READ THE PAPER →Data Release 6 publishes proper motions for 1.4 billion sources: the deepest map of how the southern sky drifts. Inside it: two new stellar streams, a hypervelocity white dwarf, and the slow unwinding of the Magellanic bridge.
EXPLORE DR6 →Cerro Miranda, 2 807 metres. Three hundred and twenty clear nights a year, eleven percent humidity, and the darkest legally protected sky in the hemisphere.
The road up switchbacks forty-one times. At the top there is no town, no glow on any horizon. Only four domes, a weather mast, and a low building where the night crew keeps coffee at exactly 61 °C, because Elena Miranda, who chose this ridge in 1984 with a borrowed theodolite and a notebook of humidity readings, insisted the coffee mattered.
She was looking for stillness. Not silence (the wind here never stops) but still air, the kind that lets a star stay a point instead of a smear. She found 0.6 arcseconds of it, a number most observatories only see a few nights a year. Here it is Tuesday.
The institute that grew on her ridge runs on a simple contract: the mountain observes, everyone shares. Every image Meridian takes is public within 24 hours. Every alert is broadcast free, worldwide, in real time. Forty-one countries have published from our archive; most of those astronomers have never seen the mountain. That is the point.
Elena Miranda surveys the ridge. Her notebook records 214 consecutive cloudless nights.
First light. A 1.2-metre reflector and a photographic plate of ω Centauri: plate 0001, still in the vault.
The Parallax program begins re-measuring every plate ever taken on the mountain.
The 8.4-metre Miranda Telescope is dedicated, two years after its namesake’s death.
Meridian begins the 72-hour cadence. The alert stream goes public, free, forever.
Data Release 6: 1.4 billion sources in motion. Pass 4 812 completes tonight.