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Astrophyzix Digital Observatory Publication
Astrophyzix.com is an independent digital observatory publication offering unpaywalled, evidence‑driven analysis and real‑time monitoring of PHAs and NEOs.
Our tracking consoles and reporting systems use and provide access to official NASA CNEOS Scout, JPL CAD, NeoWs, JPL SBDB, Horizons and NOAA observational datasets, peer‑reviewed sources, and high‑precision numerical methods (IEEE‑754 Float64, RKN4).
Designed for students, educators, researchers, and the public, every console is uniquely designed and engineered by the Astrophyzix Digital Observatory.
How to use Astrophyzix PHA/NEO/SCOUT System
User Guide - NEO / PHA Asteroid Tracking System V8.0 - Astrophyzix CNEO Observatory
CNEO OBSERVATORY - OPERATOR USER GUIDE
DOCUMENTATION / FIELD REFERENCE
NEO / PHA TRACKING SYSTEM USER GUIDE V8.0
A plain-language reference for every number, badge, colour, and control
on the Astrophyzix CNEO Observatory console. Read this once and every
screen on the tracker becomes self-explanatory.
The console answers one question: what is passing close to Earth, and
how much should it draw your attention? It blends two official NASA
feeds into a single ranked list.
Source A - Confirmed close approaches (JPL CAD)
Objects with a known, fitted orbit. These come from the JPL Small-Body
Database Close-Approach Data service, fetched through the CORS-enabled
api.nasa.gov gateway. On a card these are tagged
JPL CAD.
Source B - Unconfirmed objects (CNEOS Scout)
Newly spotted objects still on the Minor Planet Center NEO Confirmation
Page. Their orbits are preliminary and they may later be confirmed,
renamed, or removed entirely. On a card these are tagged
SCOUT NEOCP and their name ends
with (NEOCP).
Why two sources? CAD tells you about objects we have
tracked and understand. Scout tells you about objects we found only hours
or days ago and are still pinning down. Seeing both gives you the full
picture, but they must be read differently - see section 14.
The faint single line under the sync controls is the audit trail for
the data currently on screen. Every value on the page can be traced to
exactly how and when it was fetched. A typical line reads:
Which path delivered the data. api.nasa.gov-direct is the fast primary path. Names like codetabs or allorigins-raw mean a public relay was used (normal for the Scout half).
CAD v / Scout v
The API version each feed reported. If NASA changes a format, this number changes - your early warning.
source
CAD + SCOUT ideal; CAD (Scout unavailable) means only confirmed data loaded; cache means the live fetch failed and stored data is shown.
fetched
The UTC timestamp the data was actually retrieved.
validation
PASS means internal sanity checks (unit constants and a known Apophis-scale ARI benchmark) succeeded. FAIL would flag a logic or data problem.
The Copy Provenance button copies this whole record to
your clipboard for citation or bug reports.
A schematic plot of the nearest objects. Earth is the dot at the centre.
The three rings are 10, 20 and 30 lunar distances. Distance from the
centre is real (closer to the middle = closer to Earth); the compass
bearing is not real sky position - it is just rank order
so points do not overlap.
Red - PHA-class object
Blue - ordinary confirmed NEO
Amber - unconfirmed Scout object
Read it as: "are there dots near the centre?" Anything
tight to Earth coloured red or amber is what the rest of the page then
quantifies.
Each row in the list is one object. Card border tints: a red tint marks
a PHA-class object, an amber tint marks an unconfirmed Scout object.
Header line
Name
The object designation. Tapping it opens the official NASA record (JPL SBDB for CAD, the Scout page for NEOCP).
Source pill
JPL CAD confirmed, or SCOUT NEOCP unconfirmed.
Date line
CAD: closest-approach date and time, labelled TDB. Scout: the time of the object's last Scout run, in UTC.
PHA badge
PHA meets the hazard threshold, Safe does not. "Safe" means "not PHA-class in this window" - not a guarantee of zero risk.
Main grid
Miss Distance
Closest approach distance. Colour signals proximity: red under 5 LD, orange under 15 LD, grey beyond.
Velocity
Approach speed in km/s. CAD uses v_rel; Scout uses v_inf. A Scout value of 0.00 km/s means Scout did not publish a velocity for that very short arc - not a real zero (see section 14).
Est. Size
Estimated diameter in metres. The label states the basis: JPL measured, or H-derived estimated from brightness.
Abs. Mag (H)
Absolute magnitude. Lower H = intrinsically brighter = usually larger. Drives the size estimate when no measured diameter exists.
Secondary grid (differs by source)
CAD: Distance Band
The 3-sigma minimum-to-maximum approach distance in AU. A wide band means the approach distance is uncertain.
CAD: Time Uncertainty
The 3-sigma uncertainty in the time of closest approach (JPL t_sigma_f). < 00:01 means well under a minute.
Scout: Scout Scores
NEO score (0-100, likelihood it is a genuine NEO) and PHA score (0-100, likelihood it is potentially hazardous).
Scout: Observation Arc
Number of observations and the arc length in days. A short arc (under a day, few observations) means the orbit is very preliminary.
Bottom bar
ARI bar + score
The Astrophyzix Risk Index as a coloured bar and a number. See the next section.
min(20, 10 * log10(speed km/s)). Logarithmic, so extreme speeds do not run away with the score.
3. Estimated diameterup to 20 pts
min(20, diameter_m * 0.05). Caps at 400 m of estimated size.
4. PHA-class bonus+18 pts
Added if the object is PHA-class (derived for CAD, Scout phaScore for Scout).
The four terms are summed and capped at 100. Higher means "look at this
one first", nothing more.
What ARI is not. It is not the Palermo Scale or the
Torino Scale. It does not use orbital covariance, observation-arc
uncertainty, or n-body perturbation. Two objects with the same ARI can
have very different real risk. For formal impact assessment, defer to
NASA CNEOS Sentry and ESA.
Near-Earth Object - an asteroid or comet whose orbit brings it close to Earth's.
PHA
Potentially Hazardous Asteroid - official class: orbit MOID under 0.05 AU and large enough (H about 22 or brighter).
PHA-class (derived)
This console's window-local proxy when the feed lacks the official flag: H not fainter than 22.0 and minimum approach in the window under 0.05 AU. Can differ from the official MPC list.
NEOCP
NEO Confirmation Page - the Minor Planet Center list of just-discovered objects awaiting confirmation. The Scout source.
LD
Lunar Distance. 1 LD = 384,400 km, the average Earth-Moon distance.
AU
Astronomical Unit. 1 AU = 149,597,870.7 km, the average Earth-Sun distance.
TDB
Barycentric Dynamical Time - the time scale JPL uses for orbits. Differs from UTC by about 69 seconds at present, far below monitoring resolution.
Absolute magnitude (H)
An object's intrinsic brightness. Lower H = brighter = generally larger. Used to estimate size when no measured diameter exists.
Albedo
How reflective the surface is. Size from H assumes a value: nominal 0.14, band 0.25 (bright, smaller) to 0.05 (dark, larger).
v_rel / v_inf
v_rel = speed relative to Earth at the close approach (CAD). v_inf = speed relative to Earth ignoring its gravity (Scout).
3-sigma
A statistical confidence band expected to contain the true value about 99.7% of the time.
MOID
Minimum Orbit Intersection Distance - the closest the two orbits themselves come, independent of where the bodies are.
This is a monitoring and education tool, not a planetary-defence
system. For any decision that matters, use NASA CNEOS Sentry and
ESA NEOCC directly.
Scout objects are provisional. They are based on hours
of observation. They can change dramatically or vanish from the next page
load. Treat amber cards as "watch this", never as settled fact.
Scout velocities of 0.00 km/s are missing data, not real
zeros. The Scout summary feed does not always publish a velocity
for very short observation arcs; the console shows what the feed returns.
Sizes marked H-derived are estimates, often uncertain
by a factor of two or more because surface reflectivity is unknown. Sizes
marked JPL are measured and far more reliable.
PHA-class is a derived heuristic. The close-approach
feed does not return the official MPC PHA flag or MOID, so the console
derives a window-local approximation. It can disagree with the official
list.
Approach times are TDB and not converted to UTC; the
roughly one-minute difference is immaterial for monitoring but matters if
you cross-reference other tools.
The Scout half depends on public relays. If they are
rate-limited the console falls back to confirmed data only and says so in
the provenance line - the core CAD list stays reliable regardless.
