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RX Aur is a cepheid near epsilon Aurigae. I captured it in the same images I took of eps Aur with my DSLR camera. 309 observations between 2008 and 2018. The measurements are transformed to V from the green channel of the images and corrected for airmass.

submitted 22 hours ago • 0 comments

From my database of maxima for mira variables. TY Cas is a mira with one of the longest known periods. Its period also has great variations. Much of its older history comes from #DASCH and has not been known before. More miras at var.saaf.se/mirainfooc.php

submitted 5 days ago • 0 comments

RT Aur is a Cepheid variable located on the border between Auriga and Gemini. I have observed it since 2008 and made 285 observations, here plotted in a phase diagram with a period of 3.728 days. The brightness varies between magnitude 5 and 6 and for this star I have used a 10x50 binocular.

submitted 9 days ago • 0 comments

From my database of maxima for mira variables. U CMi is part of a small group of dual maxima miras. That is, it has two maxima per cycle. It is also a meandering mira, with the period varying between 396 and 427 days since 1880. More miras at var.saaf.se/mirainfooc.php

submitted 12 days ago • 0 comments

The mira star YY Aur is part of the SAAF's observation program 50 Forgotten Miras. The program started in 2012, where we adopted 50 miras that had barely been observed since their discovery. My observations are the yellow dots in the phase diagram.

submitted 16 days ago • 0 comments

From my database of maxima for mira variables. The mira BH Cru is famous for the extremely rapid increase of its period 1970-2000. From 417 to 530 days. New data from DASCH shows that it had a similar increase during 1920-1940. More miras at var.saaf.se/mirainfooc.php

submitted 18 days ago • 0 comments

In 2009-2011, an eclipse of epsilon Aurigae occurred. Eps Aur is an eclipsing variable with an unusually long period, 27 years. The star has small irregular variations in addition to the eclipse. I observed it photometrically with my DSLR camera. Light curve from SAAF, the yellow dots are mine.

submitted 20 days ago • 0 comments

From my database of maxima for mira variables. T CMi is a meandering mira, i.e. a mira where the period varies greatly but has no long-term tendency. Light blue dots are maxima from AAVSO, red ones determined by myself and dark blue are from other sources. More miras at var.saaf.se/mirainfooc.php

submitted 24 days ago • 0 comments

From my database of maxima for mira variables. The period of T Lyn has both increased and decreased over the years, but mostly decreased. The star is on my list of miras with continuous period change. The average period decrease is -0.184 days/year. More miras at var.saaf.se/mirainfooc.php

submitted 27 days ago • 0 comments

Global temperature from berkeleyearth.org/data. I made a moving average chart with data up to 2024 and then the current trends going forward. 1.5 degrees will be exceeded sometime between 2025 and 2028. 1970-2010 average increase was 0.019 deg/year, 2010-2024 0.036 deg/year.

submitted 30 days ago • 0 comments

V2331 Cyg was classified as an irregular variable (L) in the GCVS catalog before members of the SAAF discovered its true nature as an eclipsing binary in 2012. The diagram shows observations from 2012 to 2025.

submitted 31 days ago • 0 comments

RS Aql is a long-period meandering mira. Since 1895, the period has varied between 398 and 430 days. For this star, the period fluctuations have increased over time. For other stars, it may be the other way around. Could meandering be a temporary state a mira goes through?

submitted 34 days ago • 0 comments

Something strange happened to HT Cam after its short outburst in 2023. Something resembling superhumps appeared after the outburst, something that intermediate polars are not known to have. My meassured period was 2.3% higher than the stated orbital period.

submitted 38 days ago • 0 comments

From my database of maxima for mira variables. R Hya was discovered by Maraldi as variable in 1704, the period was then 495 days. Since the beginning of the 1800s, the period has with some interruptions decreased, and is now about 360 days. More miras at var.saaf.se/mirainfooc.php

submitted 41 days ago • 0 comments

The mira V603 Per has the longest known period of about two years. Its long period was discovered by members of #SAAF in 2017. It recently had its sixth maximum since SAAF began observing the star in 2013.

submitted 43 days ago • 0 comments

V405 Aur, an intermediate polar cataclysmic variable star, has had an increasing spin period since 2015. For the past two years, the rate of increase has tripled. This means that the rotation of this white dwarf is slowing down.

submitted 44 days ago • 0 comments

From my database of maxima for mira variables. Miran Z Vel in the constellation Vela, the Sail, has a meandering behavior. Its period has varied between 405 and 438 days since the 1890s. Right now, the period seems to be stable around 415-417 days. More miras at var.saaf.se/mirainfooc.php

submitted 46 days ago • 0 comments

CV Vir is a short period mira variable near M87. By using data from the #COAST telescope on Tenerife, I have got this nice phase diagram and recalculated its period. More info at var.saaf.se

submitted 48 days ago • 0 comments

From my database of maxima for mira variables. R Aql is a mira whose period has been decreasing ever since it was discovered in the 1850s. The decrease has occurred at about the same rate throughout. How long will its period continue like this? More miras at var.saaf.se/mirainfooc.php

submitted 50 days ago • 0 comments

From my database of maxima for mira variables. S Ori is a well-known meandering mira whose period varies regularly and with large amplitude. Since 1870 its average period is 421 days, but has varied between 403 and 443. More miras at var.saaf.se/mirainfooc.php

submitted 54 days ago • 0 comments

From my database of maxima for mira variables. Z Sco is a meandering mira with a highly variable period. It has varied between 340 and 375 days. The period seems to vary quite randomly and not as regularly as RU Tau does. More miras at var.saaf.se/mirainfooc.php

submitted 55 days ago • 0 comments

From my database of maxima for mira variables. DO Her is another mira with a decreasing period. It is very similar to WX Her in its behavior, but for DO Her the time series is 26 years longer. More miras at var.saaf.se/mirainfooc.php

submitted 56 days ago • 0 comments

From my database of maxima for mira variables. WX Her is a poorly observed mira with a slow but clearly decreasing period discovered by me. I don't think it has received any attention in research. More miras at var.saaf.se/mirainfooc.php

submitted 59 days ago • 0 comments

From my database of maxima for mira variables. Z Tau is a mira variable with a continuously decreasing period, although with regular plateaus. From 1886 to the present, the period has decreased from 510 to 450 days. More miras at var.saaf.se/mirainfooc.php

submitted 60 days ago • 0 comments

From my database of maxima for mira variables. RU Tau is an example of a meandering mira, where its period varies more than can be explaind by chance, but where the period is neither increasing nor decreasing in the long term. More miras at var.saaf.se/mirainfooc.php

submitted 61 days ago • 0 comments