#halpha
Live, measured metrics for the hashtag #halpha from the open social web. Every number carries a named source and the time it was fetched. Nothing is estimated.
Own #halpha
This #name is available to claim. It becomes your portal on the open agent web: this very page, a keyword you rank for by an open public stake, and a verifiable identity for AI agents. Nobody else sells a page like this for every #name.
Day-by-day usage
measured · fosstodon.org (Mastodon public tags API) · fetched 2026-09-11 17:10 UTC0 uses by 0 unique accounts across the window. Real per-day counts, not estimates. Newest bar is today so far.
Related hashtags
measured · fosstodon.org (Mastodon public search API) · fetched 2026-09-11 17:10 UTCLive pulse
measured · fosstodon.org (Mastodon tag timeline) · fetched 2026-09-11 17:10 UTCEverything below is measured over the latest 40 public posts (spanning ~15283 hours).
Posting hours (UTC) — busiest: 15:00
Languages: English (21) · German (8) · French (1)
Avg boosts / post: 0.6
Top of the latest posts
Ein paar Impressionen der #Sonnenfinsternis Some impressions of the #SolarEclipse https://www.astropage.eu/bildergalerie/sonnensystem-bilder/sonne-bildergalerie/ #Sun #Moon #Sonne #Mond #Halpha #Astronomie #Astronomy #Astrofoto #AstroImagin
The Clamshell Nebula (Sh2-119) ======================== In the rich starfields of Cygnus, the massive star 68 Cygni bathes this cloud in fierce ultraviolet light, sculpting glowing hydrogen and delicate dark dust tendrils. I captured the sc
The Bubble Maker - WR134 in Cygnus. A Wolf-Rayet star sculpting a spherical emission bubble with its relentless stellar wind over millennia. Imaged in Hubble palette mapping (HOS). NGC 6883 and β² Cygni also in the field. https://adfr.io/as
What “halpha” means
WikipediaHydrogen-alpha, typically shortened to H-alpha or Hα, is a deep-red visible spectral line of the hydrogen atom with a wavelength of 656.28 nm in air and 656.46 nm in vacuum. It is the first spectral line in the Balmer series and is emitted when an electron falls from a hydrogen atom's third- to second-lowest energy level. H-alpha has applications in astronomy where its emission can be observed from emission nebulae and from features in the Sun's atmosphere, including solar prominences and the ch
“Hydrogen-alpha” on Wikipedia (CC BY-SA) →#halpha across platforms
every network with a public tag surfaceFollow #halpha straight to each platform’s own tag page. Where a platform publishes open data we measure it above; the rest lock their numbers behind paid APIs, so we link rather than guess.
Every number above is measured from a named public API at the shown fetch time. Nothing is estimated or extrapolated. Platforms that lock their data behind paid APIs are not shown. Agents: the same numbers, as JSON, at /api/hashtags/halpha