|
|
|
 Revise  New Search
|
|
Latest Details
|
|
|
Log in to retrieve additional aliases from SIMBAD. |
|
|
| Name |
alf UMi |
|
|
| AAVSO UID |
|
| Constellation |
|
| J2000.0 |
|
| B1950.0 |
01 48 44.92 +89 01 43.7 |
| Proper motion |
|
| Galactic coord. |
123.281 +26.461 |
Other names
(Internal only)
|
|
1 UMi |
3XMM J023145.5+891548 |
AAVSO 0122+88 |
|
ADS 1477 A |
BD+88 8 |
CCDM J02319+8915A |
|
CXO J023149.5+891550 |
CXOGSG J023150.1+891550 |
HD 8890 |
|
HIP 11767 |
HR 424 |
IRAS 01490+8901 |
|
Polaris |
RAFGL 273 |
SAO 308 |
|
TYC 4628-237-1 |
WDS J02318+8916Aa |
|
(Not logged in) Add name
|
| Variability type |
|
DCEPS |
|
|
| Spectral type |
F7Ib-F8Ib |
| Mag. range |
|
1.96 - 2.03 V |
|
|
| Discoverer |
Ejnar Hertzsprung (1911) |
| Epoch |
|
| Outburst |
-- |
| Period |
3.97204 d |
| Rise/eclipse dur. |
50% (47.7 h) |
|
|
|
|
Remarks
|
|
|
Some references may be clicked to view in new window. Roll over index number to view submission details.
|
|
|
|
1 |
Otero, Sebastian Alberto
|
Triple system. From RV variations, probably spotted with P ~120 d? (2024ApJ...971..190E). |
|
2 |
Riesen, Peter
|
Polaris is the current northern pole star. This will remain the case until about 3000 AD. |
|
3 |
Otero, Sebastian Alberto
|
Period increased (3.9696 d. in 1989-1993 Hipparcos data, 3.97204 d. in 2008-2023 AAVSO V data, but the trend reversed and it is decreasing again while the amplitude stopped increasing. Changes in pulsation behaviour over the last century may be related to the binary nature of the system, as they seem to occur near each periastron passage, when the secondary (F6V) comes within 29 stellar radii of the Cepheid in its eccentric orbit with P= 29.433 yr. (2023arXiv230903257T) |
|
4 |
Otero, Sebastian Alberto
|
Amplitude decrease during the 20th century. Currently, amplitude varies but always below 0.05 mag.
Period is increasing. |
|
5 |
GCVS Team |
VB A (B 8.20m, F3V, 18.3", 218deg); SB1 (Porb = 10969d, E = 0.655 [K.W.Kamper, N.R.Evans, R.W. Lyons, JRAS Can 78, N5, 173, 1984.]). P var. There is a non-linear term in the elements: +1.9877d*10**(-7)*E**2. The amplitude of light and radial velocity variation decreased in 1982. A(V) = 0.04m (1984). |
|
|
|
|
(Not logged in) Add remark
|
|
|
|
References
|
|
|
Click reference title/citation to view in new window. Roll over index number to view submission details.
|
|
|
|
1 |
Evans, N. R.; Schaefer, G. H.; Gallenne, A.; et al., 2024, The Orbit and
Dynamical Mass of Polaris: Observations with the CHARA Array |
2024ApJ...971..190E |
|
2 |
Torres, G., 2023, The Spectroscopic Orbit of Polaris, and its Pulsation
Properties |
2023arXiv230903257T |
|
3 |
A.Arellano Ferro, ApJ 274, 755, 1983. |
1983ApJ...274..755A |
|
4 |
Hertzsprung, E., 1911, Nachweis der Veränderlichkeit von alpha Ursae
minoris |
1911AN....189...89H |
|
|
|
|
|
|
External Links
|
|
|
Links open in a new window. Not all links may be valid for this particular target.
|
|
|
|
Location
|
Go
|
Select a Location for more details.
|
|
|
|
|
Catalog Data
|
|
|
Information from selected catalogs obtained by cross-matching to 2 arc seconds using the CDS X-Match Service. These data may not be complete.
|
|
2MASS
|
J = 0.80 | H = 0.46 | K = 0.46 | J - K = 0.34 |
|
AllWISE
|
W3 = 0.58 | W4 = 0.57 | W3 - W4 = 0.02 |
|
|
|
|
Images
|
|
|
Please review Digitized Sky Survey Acknowledgment and Copyright.
|
|
|
|
Image not downloaded. Click Retrieve Image to download and view. |
Retrieve image
|
|
|
|
|
Supporting Documents
|
|
|
Click document name to open or save. Browser plug-in or other software may be required for viewing.
|
|
|
|
|
|
|
|
(Not logged in) Add document
|
|
|
|
Revision History
|
|
|
Currently approved revision is checked. Click revision number to view details of that revision.
|
|
|
|
|
