![]() It helped the Ancient Greeks, 2,200 years ago, to understand the size of our planet with remarkable accuracy. The June summer solstice has another interesting claim to fame. The situation is reversed for those living south of the equator, where it’s the shortest day of the year, during the cool months of winter. More hours of sunlight, in addition to the more direct angle of the Sun overhead, translate into warmer summertime temperatures for our planet’s summer hemisphere. For the north, it’s the longest day of the year, as the Sun traces its highest, longest path across the sky. June 21 is the Summer Solstice for the Northern Hemisphere, and Winter Solstice in the Southern Hemisphere. Credit: NASA/JPL-Caltechįacing southward early on June evenings, you’ll notice two particularly bright stars high in the sky. This sky chart for June 14 shows Jupiter with the Moon in the east before sunrise, with Saturn farther up the sky toward the south. And you’ll find Jupiter rising with the crescent Moon on June 14th. Early risers will find them on the eastern side of the sky before sun-up all month long. Turning to the morning sky, Saturn and Jupiter rise before dawn, with the Ringed Planet rising around midnight and leading brilliant Jupiter into the new day. And on the 20th through the 22nd the crescent Moon passes through, making an especially lovely grouping at dusk on June 21st. Nearby is brilliant, blue-white star Regulus – the heart of Leo, the lion. You can watch Mars and Venus draw closer together throughout the month in the western sky following sunset. Start by the other options in the VO menu and also try the Joins menu to merge the data from many original tables.Sky chart with the crescent Moon near Mars and Venus in the evening sky on June 21. It highlight the Aldebaran position in the HR plot and in the table browser.Īfter you get this basic example working you can explore all the powerful function that Topcat can offer to produce the ideal catalog for the data you need. This mark in green all the super-giant on the chart, with the other XHIP stars in red.Ĭlick on Aldebaran in Skychart, this send a single row selection to Topcat. Give a name to your subset: “super-giant”, select “skychart” and click Transmit Subset. Make a subset with a selection of the red giants branch.įrom the graphic menu Subset → Draw subset region, then select the super-giant branch with the mouse.Ĭlick the menu Subset → Finish drawing region. skychart.Ĭreate the Hertzsprung–Russell diagram in Topcat: open the menu Graphics → Plot, select Table=V_137D_XHIP, X Axis=B-V, YAxis=VMag (not Vmag!), click Flip on Y Axis. ![]() Send the table data to Skychart: Select the main table V_137D_XHIP in Topcat, open the menu Interop → Send table to. Object name: hyades, click Resolve, enter 10 for the radius (degrees).įor Catalog selection, click “By keyword”, for “Keyword” enter XHIP, click Search catalogues, select “V/137D” on the list. On Topcat click the menu VO → Vizier catalog service. On Skychart make a chart centered on the Hyades with a FOV of 20°. So launch Topcat and Skychart, connect Skychart to the hub. If you already know how to work with Topcat you can skip to the last three steps. We want to display on the chart the super-giant stars in the Hyades area using the XHIP catalog as the source of data. ![]()
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