Eclipsing binary star U Cep

[Dave Smith]

A lovely clear night on Thursday. I have been trying to get the light curve for the eclipsing binary U Cep for the previous four nights. Strangely it is because it is relatively bright that has caused me problems. What I did on Tuesday night was all discarded because the star images were saturated after just 30s. Fortunately the software rejects any such images to prevent false readings. Wednesday night I tried 3 and 5 sec images and most of the 5s were rejected. Fortunately nothing much was happening then. Thursday night I did 2s images and caught the primary minimum when the dimmer secondary star comes in front of the primary. The reason the bottom of the minimum is flat is that the secondary star is smaller than the primary and so once it is in front of the primary there is no more dimming and it then brightens up as it leaves. This type of eclipsing binary is called an EA type. (The A stands for Algol type). The arrival of dawn prevented any further play.

Dav

[DHEB]

Excellent and very interesting, Dave. What is the error margin of your measurements? Just curious.

[Dave Smith]

59 minutes ago, Cinco Sauces said:

Excellent and very interesting, Dave. What is the error margin of your measurements? Just curious.

Thank you Cinco. The error margin on these individual measurements seems to be 0.01 magnitude although the scatter of the readings would indicate more than that.

Dave

[DHEB]

Wow! That is an order of magnitude smaller than the usually quoted maximum visual acuity of 0.1 mag. Very neat!

[JeremyS]

Great result Dave!

Jeremy

[Dave Smith]

2 hours ago, Cinco Sauces said:

Wow! That is an order of magnitude smaller than the usually quoted maximum visual acuity of 0.1 mag. Very neat!

I haven't a clue how it is calculated, it is all done by the Muniwin software.

1 hour ago, JeremyS said:

Great result Dave!

Jeremy

Thanks Jeremy

Dave