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Matthew Templeton
October 8, 2010 - 1:45pm

GK Persei, or Nova Persei 1901, was a famous classical nova that nearly reached magnitude 0 in the first year of the last century.  It took GK Per several years to return to its faint state, but even now its quiescence is remarkably unquiet.  Within a few decades of outburst GK Per...

Matthew Templeton
August 23, 2012 - 10:31am

HT Cassiopeiae is an eclipsing dwarf nova of the SU Ursae Minoris (UGSU) subclass.  The UGSU typically undergo occasional short normal outbursts punctuated by rarer superoutbursts that are brighter and longer than usual.  HT Cas last underwent a superoutburst in late 2010, lasting...

Matthew Templeton
November 7, 2012 - 1:07pm

Here's a light curve that just looks cool -- the eclipsing dwarf nova IP Pegasi, where the eclipses were tracked during a recent outburst.  Dwarf novae consist of a pair of stars, one a normal dwarf star, and the other a degenerate white dwarf.  The stars orbit close...

Matthew Templeton
July 30, 2012 - 7:51am

IW Andromedae is a member of the Z Camelopardalis class of cataclysmic variables, which are dwarf novae with higher-than-average mass accretion rates.  These stars will occasionally get "stuck" in a high state between quiescence and full outburst, sometimes remaining there for...

Matthew Templeton
July 18, 2010 - 11:11am

Khi Cygni is one of the longest-studied variable stars, having been discovered in the 17th Century.  Khi Cyg (also spelled "chi Cyg") is a bright Mira variable, a pulsating star near the end of its life with a period of about 400 days, and an enormous amplitude of 10 magnitudes...

Matthew Templeton
July 30, 2012 - 7:39am

KR Aurigae is a cataclysmic variable of the VY Sculptoris class, characterized by long periods of time spent in a bright state punctuated by occasional time spent in a very faint low state.  The high state is characteristic of the novalike variables with high mass transfer rates, while...

Matthew Templeton
July 18, 2010 - 11:31am

KT Eri is a classical nova that erupted in late 2009.  This nova (Nova Eri 2009) reached magnitude 5.5 in mid-November.  It declined to about magnitude 11.5 by mid-February 2010, but remained fairly constant throughout the rest of the 2009-2010 season, with irregular flickering of...

Matthew Templeton
July 26, 2010 - 12:36pm

Mu Cephei (or "miu Cep") is a bright, red semiregular supergiant (type SRc) star, varying between 3rd and 6th magnitude.  It was dubbed "The Garnet Star" by William Herschel in 1783, and has been known to be variable since the mid-19th Century.  Mu Cephei is a...

Matthew Templeton
April 16, 2012 - 8:13am

OJ 287 is a bright BL Lac object, also known as a blazar. Blazars are supermassive black holes that reside at the centers of distant galaxies.  As the black hole accretes matter from the galaxy, some of this material is launched into space away from the...

Matthew Templeton
September 28, 2010 - 2:23pm

Omicron Ceti, also known as Mira, is justifiably one of the most famous of the variable stars, and dear to many variable star observers -- especially those who use our website, mira.aavso.org!  Omi Cet, discovered in 1596, was declared 'miraculous' by its early observers for...

Matthew Templeton
October 28, 2011 - 7:11am

A casual observer of R Aquarii over the past several decades might've noticed something slightly out of the ordinary with this Mira variable, as the depth of its minimum seems to undulate slowly over the course of many years.  An observer of the 1920s and 1930s would've seen...

Matthew Templeton
February 10, 2011 - 9:16pm

R Aurigae is a fine, bright, long-period Mira variable that's been well-observed by the amateur community for well over a century.  It's period of 450 days is high for the optically bright Miras, but periods can be much longer for some of the dust-enshrouded Miras and pulsating OH...

Matthew Templeton
November 7, 2012 - 2:50pm

R Caeli is a fine southern Mira with large amplitude and period just under 400 days.  It's one of our LPV Program stars, as well as being one of the LPVs with "humps".  In this stretch of the light curve, there's a shoulder during rising light, and it's also...

Matthew Templeton
November 6, 2012 - 10:52am

R Capricorni is an equatorial Mira accessible to most observers except those in the far northern hemisphere.  It's a carbon Mira with a strongly varying light curve and period close to one year -- about 343 days.  The AAVSO Bulletin predicts a...

Matthew Templeton
November 2, 2010 - 9:21am

R Centauri has long been identified as a peculiar Mira variable showing prominent double maxima.  The star reaches a local maximum -- one slightly fainter than the other -- with each pulsation cycle of around 550 days.  The physical cause of this isn't clear, but one...

Matthew Templeton
July 18, 2010 - 11:26am

R Coronae Borealis stars (or R CrB stars) are highly evolved stars whose light undergoes dramatic dimming events caused by dust around the star.  In mid-2007, the class prototype entered one of these dimming events, and has yet to return to its normal brightness.  Astronomers use the...

Matthew Templeton
May 14, 2013 - 10:12am

R LMi is a fine northern Mira variable with a substantial range, and a period just over one year (372 days).  R LMi shows cycle-to-cycle variations like many Mira variables do, and so it never quite puts on the same show from year to year.  The star is a known maser source, and it...

Matthew Templeton
April 7, 2011 - 1:36pm

R Normae is another famous Mira exhibiting the peculiar phenomenon of double maxima -- two bright maxima per pulsation cycle.  The reason for this behavior isn't known for certain, but two possibilities are (a) resonances between two pulsation modes, or (b) the formation of shocks in...

Matthew Templeton
August 6, 2010 - 12:09pm

R Scuti is a popular target for variable star observers and has been for well over a century (its observational record dates to the late 18th century).  R Scuti is an RV Tauri star, which are highly evolved pulsating giant stars having periods from  tens of days to 100 days or more....

Matthew Templeton
October 1, 2010 - 2:50pm

RR Pic (Nova Pictoris 1925) is an example of a slow nova, which are classical nova systems whose light output changes on timescales of months and years rather than the days and weeks of typical novae.  Slow novae are believed associated with lower-mass white dwarf primaries, perhaps as...

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