Poчetna     To Survive in the Universe    
Services
    Why to Inhabit     Top Contributors     Астро Фотографије     Колекција     Форум     Blog New!     FAQ(Често постављана питања     Улогуј се  
→ Adopt this star  

HD 209444


Садржај

Слике

Уплоадјуј своје слике

DSS Images   Other Images


Везани чланци

A magnitude limited stellar X-ray survey and the F star X-ray luminosity function
An X-ray survey has been conducted of stars brighter than visualmagnitude 8.5 that have serendipitously fallen into the fields of viewof the Imaging Proportional Counter of the Einstein Observatory. Thesurvey includes 227 separate 1 x 1 deg fields, containing 274 stars witha visual magnitude of no more than 8.5 and covering a wide range ofspectral types and luminosity classes. X-ray emission was detected from33 stars, and upper limits have been determined for the remainder of thesample. F type stars dominate the detected sample, and most of these areshown to be dwarfs. An X-ray luminosity function for dF stars has beendeduced, and reveals that the average 0.2-4.0 keV luminosity of thesestars is around 10 to the 29th erg/sec. Constraints have been placed onthe high luminosity tails and medians of the X-ray luminosity functionsfor other types of stars.

Додај нови чланак


Линкови у сродству са темом

  • - Нема линкова -
Додај нови линк


Чланови следећих група \:


Посматрања и Астрометриски подаци

Сазвежђа:Водолија
Ректацензија:22h03m30.07s
Deклинација:-05°41'33.4"
Apparent магнитуда:7.638
Даљина:143.678 parsecs
Proper motion RA:57.5
Proper motion Dec:23.7
B-T magnitude:8.916
V-T magnitude:7.744

Каталог и designations:
Proper имена
HD 1989HD 209444
TYCHO-2 2000TYC 5230-647-1
USNO-A2.0USNO-A2 0825-19532520
HIPHIP 108895

→ Захтевај још каталога од VizieR