⭐ Recommended observational targets

(Global participation)

This page lists variable stars well suited for long-term differential photometry within the Psi-Continuum observational pilot.

The targets are intentionally chosen to be:

• well-studied and physically smooth,
• observable with small to medium amateur telescopes,
• suitable for long-term, repeatable monitoring,
• easy to combine across different observers and locations.

The scientific goal is not stellar astrophysics, but testing the reproducibility and stability of observational data under realistic conditions.

🔴 RR Lyrae stars

RR Lyrae stars have short periods and relatively large amplitudes, making them excellent reference signals for consistency tests.

RR Lyrae

• Constellation: Lyra
• Magnitude range: V ≈ 7.1 – 8.1
• Period: ~0.57 days
• Visibility: observable from most northern latitudes

Comment:
A classical reference object. Suitable even for first test observations.

X Arietis

• Constellation: Aries
• Magnitude range: V ≈ 9.5 – 10.4
• Period: ~0.65 days
• Visibility: autumn–winter (northern hemisphere)

Comment:
Convenient for winter observing windows.

RV Ursae Majoris

• Constellation: Ursa Major
• Magnitude range: V ≈ 9.8 – 10.9
• Period: ~0.47 days
• Visibility: circumpolar for many northern observers

Comment:
Especially suitable for automated or semi-automated setups.

🔵 Classical Cepheids

Classical Cepheids have longer periods and exceptionally smooth light curves, ideal for long-term stability tests.

δ Cephei

• Constellation: Cepheus
• Magnitude range: V ≈ 3.5 – 4.4
• Period: ~5.4 days
• Visibility: northern hemisphere

Comment:
Very bright object. Short exposures or mild defocusing may be required.

η Aquilae

• Constellation: Aquila
• Magnitude range: V ≈ 3.5 – 4.4
• Period: ~7.2 days
• Visibility: summer months (both hemispheres)

Comment:
Well suited for testing long-period stability.

RT Aurigae

• Constellation: Auriga
• Magnitude range: V ≈ 5.0 – 5.8
• Period: ~3.7 days
• Visibility: winter–spring (northern hemisphere)

Comment:
Convenient for winter observing campaigns.

🌍 Choosing targets worldwide

Participants are not limited to the list above.

You may select any RR Lyrae star or classical Cepheid that:

• lies in the magnitude range V ≈ 7–12 (or brighter with short exposures),
• is well observable from your latitude,
• has 2–3 stable comparison stars in the same field,
• can be monitored repeatedly over several weeks.

If uncertain, participants are encouraged to contact the project coordinator to agree on a suitable target.

✅ Practical recommendations

• Choose one target per observing season
• Do not switch targets mid-series
• Regularity and repeatability matter more than phase coverage
• One well-observed object is more valuable than many sparse datasets

For automated systems:

• prefer targets with long visibility windows,
• minimize configuration changes during the campaign.

⚠️ Important notes

• Extremely high precision is not required
• Absolute photometric calibration is not necessary
• Realistic observing conditions are part of the experiment

🔎 If you would like to propose a different target
or need help selecting an object appropriate for your equipment and location,
please contact the project coordinator.

📬 Contact

Project coordinator:
Dmitry Vasilevich Klimov
Independent researcher

📧 d.klimov.psi@gmail.com
🌐 https://psi-continuum.org