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TW Cep is a mira in the SAAF's "50 Forgotten Miras" program. The star was discovered in 1914 by d'Esterre, an English amateur astronomer who had an observatory in Tatsfield, Surrey. The current period of 282 days seems fairly stable.

submitted 3 days ago • 0 comments

VZ CMi is a mira in the SAAF's 50 Forgotten Miras program. Discovered in 1927 by Frank E. Ross at Yerkes. The yellow dots are my observations, the green ones by other SAAF observers.

submitted 15 days ago • 0 comments

RS Ori is a Cepheid in the northern part of Orion. I started observing it in 2011 and so far I have made 133 visual observations. I find it easy to observe as it has 3 close companion stars of magnitude 8.0, 8.3 and 8.8.

submitted 20 days ago • 0 comments

GM Cam is one of the SAAF's 50 Forgotten Miras. It has not been a known variable for very long, having been discovered in 1999 by Kesao Takamizawa. Before SAAF began observing it, it had no known period. 13 years of our data have now given it a period of 368.7 days.

submitted 27 days ago • 0 comments

From my database of maxima for mira variables. W Dra is a mira with a clearly increasing period. Since 1895, the period has increased from 253 to 290 days, an average of 0.3 days per year. In addition, the star has normal random variations in its period. More miras at var.saaf.se/mirainfooc.php

submitted 37 days ago • 0 comments

YZ Cam is a mira in the SAAF's 50 Forgotten Miras program. It was discovered in 1949 by Balfour S. Whitney, Oklahoma University. From #DASCH data going back to 1895, its period appears to be fairly stable. The current period is 360.3 days. Since 1895, the average period is 360.12 days.

submitted 44 days ago • 0 comments

U Aql is a bright classical Cepheid discovered by Edwin Sawyer in 1886. I have observed it on 141 occasions since 2009. The diagram below is a phase diagram with my observations and the best period of 7.02429 days.

submitted 52 days ago • 0 comments

UZ Cam is one of the 50 forgotten miras. It is also on my list of meandering miras and has a period that has varied between 224 and 240 days. Discovered in 1934 by Sergei Beliavski. Gunnar Rynefors, a Swedish amateur astronomer, observed it extensively from 1971-1983.

submitted 58 days ago • 0 comments

From my database of maxima for mira variables. T Hya is a mira with a meandering period. The period has varied between 282 and 302 days. One gets the impression that the meandering behavior could be more of a temporary outburst than a permanent feature. More miras at var.saaf.se/mirainfooc.php

submitted 64 days ago • 0 comments

TT Cam is a mira that is said to have been discovered by a certain H. Gitz in Moscow in 1935. Does anyone know anything more about this astronomer? Gitz gave the period as 252.6 days and it seems to match quite well with what we have obtained after 13 years of observations.

submitted 68 days ago • 0 comments

V483 Aur is a mira that is part of the #SAAF observation program 50 Forgotten Miras. It was discovered by Kesao Takamizawa in 1999 and its period was unknown before we started observing it. The current period from our data is 303.4 days.

submitted 72 days ago • 0 comments

From my database of maxima for mira variables. R Cen is a long-period mira belonging to a small group that has two maxima per cycle in its light curve. Since 1870, its period has decreased from 570 to 500 days, although not at a steady rate. More miras at var.saaf.se/mirainfooc.php

submitted 78 days ago • 0 comments

The mira star DU Aur is part of the SAAF's observation program 50 Forgotten Miras. My observations are the yellow dots in this phase diagram. Current period is 275.0 days. Older data from #DASCH indicate that the period has been fairly constant since 1900 onwards.

submitted 87 days ago • 0 comments

Eta Aql is a bright classical Cepheid and the first discovered in its class. The variability was found in 1784 by Edward Pigott. A month later his friend John Goodricke found the next Cepheid, delta Cep, which gave its name to the class. Here are my visual observations of the star, 306 since 2009.

submitted 92 days ago • 0 comments

From my database of maxima for mira variables. T Ari is another mira in my meandering mira group. It has a fairly small amplitude of between 2.5 and 3 magnitudes and lies in the borderland between semi-regular red giants variables and miras. More miras at var.saaf.se/mirainfooc.php

submitted 96 days ago • 0 comments

Phase diagram of the color indices for the mira UZ Cam. Red dots: R-V magnitude, blue dots: B-V magnitude. This is typical behavior, R-V varies quite a lot and follows the cycle, while B-V has a significantly smaller variation that is not always clearly connected to the cycle.

submitted 101 days ago • 0 comments

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 104 days 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 109 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 112 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 116 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 120 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 122 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 124 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 128 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 131 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 134 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 135 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 138 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 142 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 144 days ago • 0 comments