#astrophysics

Live, measured metrics for the hashtag #astrophysics from the open social web. Every number carries a named source and the time it was fetched. Nothing is estimated.

hashtag.org network · sponsored

Own #astrophysics

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.

$5.00/ year · 12-character #name
Claim #astrophysics$5.00/yrBuy on hashtag.space (web3)
card via hashtag.org · tokens via hashtag.space
97
Uses / 7 days
Mastodon
51
Accounts / 7 days
Mastodon
40
Recent posts
Mastodon
~0.5/hr
Recent pace
Mastodon · last 40
3.1
Avg reactions / post
Mastodon · last 40
Reddit posts / month
Reddit search
Open-web mentions
hashtag.org Firehose

Day-by-day usage

measured · mastodon.online (Mastodon public tags API) · fetched 2026-09-07 22:58 UTC
12
09-01
18
09-02
15
09-03
14
09-04
8
09-05
13
09-06
17
09-07

97 uses by 51 unique accounts across the window. Real per-day counts, not estimates. Newest bar is today so far.

Related hashtags

measured · mastodon.online (Mastodon public search API) · fetched 2026-09-07 22:58 UTC

Live pulse

measured · mastodon.online (Mastodon tag timeline) · fetched 2026-09-07 22:58 UTC

Everything below is measured over the latest 40 public posts (spanning ~74 hours).

Posting hours (UTC) — busiest: 14:00

00:0012:0023:00

Languages: English (30) · French (1)

Avg boosts / post: 5.9

Top of the latest posts

  • In 1925, 24-year-old graduate student Cecilia Payne calculated that the Sun and other stars were composed overwhelmingly of hydrogen and helium—a result so contrary to accepted astronomy that senior astronomer Henry Norris Russell called it

    Project Gutenberg@[email protected]1161612026-09-07 08:11 UTCView post →
  • Welcome to a Comet, from Lander on Surface The Philae lander of the European Space Agency Rosetta mission is safely on the surface of Comet 67P/Churyumov-Gerasimenko, as these first two images from the lander CIVA camera confirm. One of the

    astropic@[email protected]242026-09-05 06:00 UTCView post →
  • Dark Moon, Dramatic Plume Below a darkened Enceladus, a plume of water ice is backlit in this view of one of Saturn most dramatic moons. This image was captured by NASA Cassini spacecraft. More: https://images.nasa.gov/details/PIA14599 Cred

    astropic@[email protected]112026-09-07 22:00 UTCView post →

What “astrophysics” means

Wiktionary · Wikipedia

astrophysics

  • nounThe branch of astronomy or physics that deals with the physical properties of celestial bodies and with the interaction between matter and radiation in celestial bodies and in the space between them.
Full entry on Wiktionary →

Astrophysics is a science that applies the methods and principles of physics and chemistry in the study of astronomical objects and phenomena including the universe. As one of the founders of the discipline, James Keeler, said, astrophysics "seeks to ascertain the nature of the heavenly bodies, rather than their positions or motions in space—what they are, rather than where they are", which is studied in celestial mechanics. Astrophysics is also used when designing and plotting courses for space

Astrophysics” on Wikipedia (CC BY-SA) →

#astrophysics across platforms

every network with a public tag surface

Follow #astrophysics 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/astrophysics