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Alert Notice 621: Optical monitoring of NSV 24045 = HD 163296

March 15, 2018: Evan A. Rich (Ph.D. candidate, University of Oklahoma), and Drs. John Wisniewski (University of Oklahoma), John Tobin (University of Oklahoma), Carol Grady (Goddard Space Flight Center), and Mike Sitko (University of Cincinnati) have requested AAVSO assistance in monitoring the bright (6.9 V) Young Stellar Object NSV 24045 (HD 163296) from now through September 2018.

Alert Notice 590: V1117 Her observations requested

August 7, 2017: AAVSO Young Stellar Object (YSO) Section leader Michael Poxon (Great Plumstead, Norfolk, UK) requests coverage of the YSO V1117 Her.

He writes: "The peculiar YSO V1117 Herculis has undergone a second, rapid fade and recovery only a few days after its recovery from another rapid fade. Observations, both visual and multiwavelength, are encouraged, since the behaviour of this star's historical fading episodes may indicate rapidly-changing evolution of the protoplanetary clumps in the circumstellar disc.

Alert Notice 574: Monitoring of EPIC 204278916 requested

April 25, 2017: Dr. Carlo Manara (ESA Science and Technology SCI-S, the Netherlands) and colleagues have requested AAVSO assistance in monitoring the young, disk-bearing low-mass (M type) pre-main-sequence star EPIC 204278916 (2MASS J16020757-2257467).

The YSO Zoo

...and welcome to the Zoo!

Part of the reason why a YSO section is needed is to try and make some sense of how the different types of variable star fit into some sort of scheme. Should we view the various types as distinct, or should we look at behaviour instead? Pursuing the zoo theme for a while, how do the various types of YSO fit into the interstellar ecosystem?

The What and Why of YSO's!

This page will present a brief introduction to Young Stellar Objects and Star Formation. What it is and why we are so darn interested by the whole thing - and what we, as amateur astronomers, can do in helping to discover more about the amazing, violent processes that are going on, as you read this, in deepest space (at least that's what most of us are; apologies to you lucky visitors who actually get paid for doing astronomy)

Special Notice #209: Nightly monitoring of TW Hya in support of HST observations

May 17, 2010: Dr. Michael Sitko (U. Cincinnati) requests observations of the young stellar object TW Hya in support of upcoming Hubble Space Telescope observations. TW Hya is believed to be a T Tauri star that varies between magnitudes 10.5 and 12.2. TW Hya will be observed with the HST STIS instrument as part of a larger program to study the properties of potentially planet-forming disks around young stars. The star will be observed in the ultraviolet to search for time-variability in the gas in the inner accretion disk.

Alert Notice 488: Observations of AA Tau requested to schedule XMM-Newton

August 1, 2013: Dr. Hans Moritz Guenther (Harvard-Smithsonian Center for Astrophysics) has requested nightly observations of the classical T Tauri star AA Tau in order to schedule x-ray observations with XMM-Newton that have been planned for between 2013 August 15 and September 15.

Alert Notice 478: Transformed photometry of young stars in Cha requested

January 16, 2013: Dr. Péter Ábrahám (Konkoly Observatory, Budapest, Hungary) has requested the assistance of AAVSO observers in monitoring eight young stars in Chamaeleon in support of photometry he and his colleagues will be obtaining with the VLT/ISAAC (infrared) and Herschel Space Observatory (far-infrared) during January-February 2013.


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