October 30
The River Displaced
Sun Position
The Sun is in Scorpius near -18° declination. The Northern Hemisphere is within six weeks of its shortest day; the Southern Hemisphere within six weeks of its longest.
Sky Highlight
The Southern Taurid meteor shower continues to ramp toward its November peak, and late October often produces the shower's brightest individual members. The Halloween period around October 31 has historically been associated with elevated fireball reports from this shower, a coincidence that has nothing to do with the calendar date and everything to do with where Earth sits in the debris stream.
Deep Sky Object
NGC 1232, a spiral galaxy about 65 million light-years away. NGC 1232 in Eridanus is a large, nearly face-on spiral with two well-defined arms and a small companion galaxy visibly tugging at its outer structure, one of the better-resolved examples of active tidal disruption accessible from southern and mid-latitude northern observing sites. Best from Southern Hemisphere and low northern latitudes; accessible with effort from Northern Hemisphere mid-latitudes.
Featured Star
Acamar (θ Eri) is a white giant and white main-sequence pair (A4III + A1V) about 161 light-years away, a clean spectroscopic and visual binary, both components white, whose only drama is historical: it once ended the river, and the discovery of the southern sky reassigned that title to Achernar, 25 degrees further south. Acamar, the former end of the river, displaced when the deeper south was mapped.
Around This Date
- October 30, 1981Venera 13 launched toward Venus; it would land and transmit the first color surface images of Venus in March 1982, surviving 127 minutes in conditions of 465°C and 90 atmospheres of pressure.
- October 31, 1992Pope John Paul II issued a formal statement acknowledging that the Catholic Church's condemnation of Galileo had been an error, closing a case opened 359 years earlier.
The river's end moved when human eyes could finally see far enough south, the sky did not change, only the map.