This is the Skywatch Line for Monday and Tuesday, October 14th and 15th, written by Joe Slomka.
The Sun sets at 6:15 PM; night falls at 7:49. Dawn begins at 5:34 AM and ends with the Sun rising at 7:08.
Jupiter and Saturn are no longer the only planets visible in the evening sky. Mercury and Venus, both in Virgo, rise shortly before Sunset, can be found low in the Southwest, separated by about 8. Venus is brightest, blazing with minus 4th magnitude and appearing about 96% illuminated, 6degrees above the horizon. Mars is a bit dimmer and about 71% lit and appears a bit higher than Venus. Both require binoculars to find them amid the setting Sun’s glare. Both set by 7 PM. Astronomy magazines and websites provide finder charts to aid observers.
Jupiter still occupies Ophiuchus, glowing with minus 2nd magnitude and appearing about 21 above the southwestern horizon. It sets at 9:12 PM.
Saturn also remains in Sagittarius, shining with zero magnitude. It trails Jupiter by about 2 hours and appears moderately low in the South. The Ringed Planet is best observed at 6:25 PM and sets about 11 PM. Saturn appeared in the news last week. The Minor Planet Center announced that Jupiter is no longer king of the planets. Astronomer Scott Shepard discovered 20 new moons for Saturn for a total of 82 satellites; Jupiter held the record at 79. Shepard first photographed them in 2004 and 2005, but spent years determining their orbits and predicting their position, so that other astronomers could verify the discovery. Most of the new moons are about 5 kilometers wide (3 miles); 17 of them orbit backwards in respect to Saturn and the other satellites.
Late evening reveals Neptune, still in Aquarius, near the star Phi Aquarii. It shines with 8th magnitude and appears a tiny 2 arc-seconds in size. It is best observed at 10:33 PM and sets at 4:12 AM. Uranus holds court in Aries, shines with 5th magnitude, appears a bit larger than Neptune, and is about 53 high. It is best viewed at 1:33 AM and remains up all night. Again, astronomy magazines and websites provide finder charts.
The 16-day-old Monday’s Moon rises in Cetus at 7:03 PM, appearing about 98% lit and blazing with minus 12th magnitude. Tuesday, the Moon migrates to Aries and appear slightly thinner and dimmer; it rises at 7:30 PM. On both days, the Moon remains up past Sunrise.
Mars makes his reappearance in our Dawn sky. In Virgo, it rises at 5:53 AM, appearing about 99% lit, glowing with first magnitude and appearing about 8 above the eastern horizon. Again, binoculars are suggested.
Besides Saturn, the Nobel Prize in Physics also made headlines. Three astronomers will be honored. James Peebles won the prize for his work on the Cosmic Microwave Background (CMB). In 1929, American astronomer Edwin Hubble discovered that galaxies were flying away from each other. Belgian Catholic Priest-astronomer George Lemaitre, using Einstein’s theories, proposed a sudden creation and expansion of the universe in 1939, now known as the Big Bang. James Peebles studied the Big Bang and realized that it would leave a trace of cosmic radiation. Bell Labs engineers Wilson and Penzias, while trying to understand static in radio transmissions, realized that the static was the CMB leftovers of the Big Bang. They were rewarded with the Nobel Prize in 1978. Now, the Nobel Prize was awarded to Peebles for his research.
In addition, Michel Mayor and Didier Queloz shared the Nobel Prize with Peebles for their discovery of the first exoplanet orbiting a sun-like star, 51 Pegasi b. To date, over 4000 exoplanets have been discovered, with about an equal number awaiting confirmation.