0942-62 l Carinae

( Note to readers, ‘l’ is el, not one )

This is the first variable to be observed by me, some half a century ago. Like last month's variable, it is a naked eye star which makes it an ideal object for beginners.

l Car is a Cepheid of rather long period, 35.5 days. Its amplitude is one magnitude or rather more and its visual magnitude at maximum is 3.5 .

Cepheids are of course well known as distance indicators as was first pointed out by Henrietta Leavitt back in 1912 and elaborated on by Harlow Shapley in 1917.

It is worth looking at every few days. Compare it with the adjacent stars m, mag 4.5, h, mag 4.1 and upsilon, mag 3.1 (All these are shown in Norton's Star Atlas, amongst others). When you have found the period to your own satisfaction, you could calculate its distance, following the directions which Eben van Zyl gave a few years ago when he invited Johannesburg centre members to do just that.

Enjoy the exercise!
Danie Overbeek.

More on Nova Vela 1999

Canopus promised its readers a light curve of Nova Vel 1999, now known as V382 Vel.
Here is the raw data from 23^rd May through 17^th June plus a graphical representation thereof.
Cheers,
Danie.

-104051 V382 VEL Julian Day 322.2 Mag3.1 ( JD 322 is 1999 05 23 and so on)

322.3   2.7       323.2   3.9 324.2   3.5 326.2   4.3 327.2   4.3 329.2   5.2 330.2   5.4 331.2   5.4 332.2   5.5 334.2   5.8 335.2   5.8 336.2   5.8 337.2   5.8 338.2   6.0 339.2   6.0 341.2   6.4 343.2   7.4 344.2   7.0 346.2   7.0 347.2   6.9