Southern targets guide: objects invisible from the UK

Adds TARGETS.md, a target guide for the southern iTelescope sites (Siding
Spring Q62, Deep Sky Chile X07) built around UK visibility: from lat 51.5°N
anything below dec -38° never rises and dec -25° to -38° culminates under
~15° altitude. Targets are tiered accordingly (never visible vs hopeless),
grouped by region (Magellanic Clouds, Carina/Crux, Centaurus, Ara/Scorpius
tail, far-southern galaxies, SNR/planetaries), and each is matched to the
best scope from TELESCOPES.md with the field-of-view reasoning in the notes.

Includes a seasonal booking calendar (evening sky by quarter from the
southern sites, with the Q62 30-35° minimum-elevation caveat), a suggested
first campaign for July-August (free T33 globulars, T71 narrowband on Ara/
Scorpius, T73 on NGC 6744, then T8 on the Magellanic Clouds in Oct-Nov),
and cost-shape notes (fast scopes for nebulae, dark-of-moon for LRGB).

README links the new guide; state/TODO.md records the addition.
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- **[TELESCOPES.md](TELESCOPES.md)**: the full review, grouped by observatory, with a
"choosing a telescope" guide at the end.
- **[TARGETS.md](TARGETS.md)**: southern-sky targets invisible from the UK, matched
to scopes and to the time of year to book them.
- **[data/itelescope-telescopes.csv](data/itelescope-telescopes.csv)**: snapshot of
the network's maintained specs sheet (source of truth for the numbers).
- **state/**: project state under the Default Workflow.

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TARGETS.md Normal file
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# Southern targets: what the UK can never show you
A target guide for imaging objects that are invisible (or hopeless) from the UK,
using the southern half of the iTelescope network: Siding Spring, Australia (Q62)
and Deep Sky Chile (X07). Companion to [TELESCOPES.md](TELESCOPES.md).
## The visibility rule from the UK
From latitude 51.5°N (southern England), an object's maximum altitude is
`90° - 51.5° + declination`:
- **Dec below about -38°: never rises.** These objects cannot be imaged from the UK
at all, ever.
- **Dec -25° to -38°: technically rises, practically hopeless.** Culminates under
~15° altitude, buried in atmosphere and murk.
- Dec -10° to -25°: imageable from the UK but always low and compromised; far better
from the southern sites.
Everything below is grouped by those tiers, then matched to scopes and to the time
of year when it is best placed from the southern sites.
## Tier 1: never visible from the UK (dec < -38°)
### The Magellanic Clouds (the headline act)
| Target | Dec | Best scope | Notes |
|---|---|---|---|
| Large Magellanic Cloud | -69° | T8 | The whole LMC just fits T8's 4 x 4 degree field |
| Tarantula Nebula (NGC 2070) | -69° | T73, T17 | Core detail; the finest emission nebula in either sky |
| Small Magellanic Cloud + 47 Tucanae | -72° | T8 | Both in a single T8 frame, a unique composition |
| 47 Tucanae (NGC 104) alone | -72° | T33 (free), T73 | Second-finest globular in the sky |
### Carina and Crux region
| Target | Dec | Best scope | Notes |
|---|---|---|---|
| Eta Carinae Nebula (NGC 3372) | -59° | T71 | Fills T71's 2.7 x 1.8 degree field perfectly; narrowband showpiece |
| Carina to Crux widefield | -60° | T70 | The richest stretch of the Milky Way in one 8-degree frame |
| Southern Pleiades (IC 2602) | -64° | T71, T75 | Bright open cluster |
| Running Chicken (IC 2944) | -63° | T71, T75 | Emission nebula with Bok globules |
| Wishing Well Cluster (NGC 3532) | -58° | T71 | Reportedly the best open cluster in the sky |
| Coalsack + Southern Cross | -60° | T70 | Dark nebula composition |
### Centaurus and the southern globulars
| Target | Dec | Best scope | Notes |
|---|---|---|---|
| Omega Centauri (NGC 5139) | -47° | T59, T17 | The largest globular cluster known; needs the ~40 arcmin fields |
| Centaurus A (NGC 5128) | -43° | T17, T32, T73 | Iconic dust-lane radio galaxy |
| NGC 4945 | -49° | T73 | Big edge-on spiral, underimaged |
| NGC 6752 (Pavo globular) | -60° | T33 (free) | Third-brightest globular |
### Ara, Norma and the Scorpius tail
| Target | Dec | Best scope | Notes |
|---|---|---|---|
| Fighting Dragons of Ara (NGC 6188) | -49° | T71 | Dramatic narrowband target |
| Prawn Nebula (IC 4628) | -40° | T71, T75 | Large, faint, great in Ha |
| NGC 6231 + Table of Scorpius | -42° | T71 | Rich cluster region |
### Far-southern galaxies
| Target | Dec | Best scope | Notes |
|---|---|---|---|
| NGC 6744 (Pavo) | -63° | T73, T17 | Milky Way lookalike spiral |
| NGC 1313 (Topsy-Turvy) | -66° | T73 | Distorted starburst spiral |
| NGC 1566 (Spanish Dancer) | -55° | T73 | Grand-design face-on spiral |
| NGC 2070 region galaxies | -69° | T17 | See Magellanic section |
### Southern nebulae, supernova remnants and planetaries
| Target | Dec | Best scope | Notes |
|---|---|---|---|
| Vela SNR | -45° | T70 | Huge filamentary shell, needs the 8-degree field |
| Gum Nebula | -43° | T70 | 36 degrees across; even T70 mosaics it |
| Southern Ring (NGC 3132) | -40° | T73 | Small bright planetary |
| Toby Jug Nebula (IC 2220) | -59° | T73 | Reflection nebula |
## Tier 2: hopeless from the UK (dec -25° to -38°), excellent from the south
| Target | Dec | Best scope | Notes |
|---|---|---|---|
| Cat's Paw (NGC 6334) | -36° | T71 | Narrowband showpiece |
| War and Peace (NGC 6357) | -34° | T71 | Pairs with the Cat's Paw in one T75 framing |
| NGC 1365 (Great Barred Spiral) | -36° | T73, T17 | The archetypal barred spiral, Fornax |
| Fornax cluster core | -35° | T17, T32 | Galaxy cluster field |
| M83 (Southern Pinwheel) | -30° | T73, T17 | Face-on spiral, superb from Q62/X07 |
| NGC 300 and NGC 55 (Sculptor) | -37°/-39° | T17, T75 | Nearby resolved spirals |
| NGC 253 (Sculptor Galaxy) | -25° | T17, T32 | Huge dusty starburst, low and ruined from the UK |
| Corona Australis dust complex | -37° | T71, T75 | Reflection nebula and dust river |
## When to book what (from the southern sites)
Seasons refer to what is well placed in the evening-to-midnight sky at Siding Spring
and Deep Sky Chile. Siding Spring scopes have 30-35 degree minimum elevation limits,
so aim within a few hours of culmination; T70 in Chile can go to the horizon.
- **Jan-Mar:** Tarantula and the LMC, NGC 1313, Vela SNR and the Gum Nebula, Carina
rising late evening.
- **Apr-Jun:** Eta Carinae at its best, Crux and the Coalsack, Omega Centauri,
Centaurus A, NGC 4945, the Musca dark nebulae.
- **Jul-Sep (now):** the Scorpius tail and Ara at the zenith: Cat's Paw, War and
Peace, Prawn, NGC 6188, NGC 6231; NGC 6744; Corona Australis; 47 Tucanae and the
SMC in the second half of the night.
- **Oct-Dec:** Magellanic Cloud prime time, 47 Tucanae, Sculptor galaxies (NGC 253,
55, 300), Fornax cluster and NGC 1365, NGC 1566.
## A sensible first campaign (July-August)
1. **Free warm-up on T33** (30 min/day, Siding Spring): 47 Tucanae or NGC 6752 in
LRGB across a few nights. Costs nothing, learns the booking system.
2. **T71 narrowband run** (Chile, f/2.8): NGC 6188 or the Cat's Paw + War and Peace
region. Fast optics keep the bill down; use the standard 300 s calibrated subs.
3. **T73 galaxy shot**: NGC 6744, currently well placed, as an LRGB target.
4. **Book ahead for October-November:** T8 for the LMC (or SMC + 47 Tuc in one
frame): the single most "you cannot do this from the UK" image on the network.
## Cost-shape notes
- Fast scopes (T71 f/2.8, T75 f/3.8, T70 f/3.5) reach depth in the least imaging
time, which is what you pay for: prefer them for nebulae.
- The two free scopes cover both hemispheres of this list poorly (T68 is northern)
but T33 covers southern globulars and compact targets well.
- Moonlight: narrowband targets (Carina, Ara, Scorpius nebulae) tolerate moon;
save galaxy and globular time (T73, T17, T8 LRGB) for dark-of-moon bookings.

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- 2026-07-17: specs sheet snapshotted to data/itelescope-telescopes.csv (24 scopes).
- 2026-07-17: TELESCOPES.md written: per-scope reviews for all 23 active telescopes
plus a choosing guide (T74 noted as in commissioning, no specs published).
- 2026-07-18: TARGETS.md written: southern targets invisible from the UK (dec tiers
from lat 51.5°N), matched to Q62/X07 scopes, seasonal booking calendar, and a
July-August starter campaign (T33 free, T71 narrowband, T73 galaxy, T8 LMC later).
## In progress