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<p class="MsoNormal">As well as this one.<o:p></o:p></p>
<p class="MsoNormal">carlos<o:p></o:p></p>
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<p class="MsoNormal"><b><span style="font-size:12.0pt;color:black">From: </span></b><span style="font-size:12.0pt;color:black"><faculty-talk-bounces@physics.tamu.edu> on behalf of nsuntzeff <nsuntzeff@tamu.edu><br>
<b>Date: </b>Wednesday, April 25, 2018 at 12:42 PM<br>
<b>To: </b>announce <announce@physics.tamu.edu><br>
<b>Subject: </b>[Faculty-talk] [Announce] more on Gaia<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Dear All, <o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">One of the early puzzles from Gaia is the following diagram. You are looking at the velocity components of the stars within 200pc, in the coordinate system of x (toward the Galactic center which has the “U” component which should be defined
positive in the direction of the Galactic Center) and the y component toward the direction of rotation at the solar position. Since the sun is rotating into a non-rotating halo, the halo and thick disk stars will have highly negative velocities on the lower
half of the diagram. The clumpiness near U=0 and V=-20 appears to be significant structure in the *disk* of our Galaxy. A good friend of mine, now passed away, Olin Eggen, discovered “moving groups” of stars which had similar kinematical properties. For many
years he fought to get his ideas into the literature, and finally did, but with many astronomers skeptical of his results. I wish he were here to see this. <o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Some of these clumps must be the Hyades and the Pleiades groups which have been known for many years. But the others?<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><img width="527" height="473" id="_x0000_i1025" src="cid:image002.png@01D3DCC4.12A59AA0"><o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">much more cool stuff at <a href="https://urldefense.proofpoint.com/v2/url?u=https-3A__www.cosmos.esa.int_web_gaia_home&d=DwMGaQ&c=oqyuZuih6ykib6aKiBq22_bich4AVfYGoLertJN0bEc&r=hjwEO_XYlnwAQWUGeaCrW47w4mK-Al28-BKyRvaivBs&m=9AwsXA3lLRmvfUCHyPpv-WHMJZWjusjcqb6tz3n9duE&s=iyJqLK5VRdnze1u_0-bzrBhr_Ja_Cj-OOtUykC1Vh_I&e=">https://www.cosmos.esa.int/web/gaia/home</a>,<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">cheers nick<o:p></o:p></p>
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