Sixty years ago, physicist Enrico Fermi asked the question, “Where is everybody?” He was referring to the possibility that life existed beyond Earth. Science writer John Gribbin, in his latest book, “Alone in the Universe,” answered Fermi’s question by saying nowhere — or at least not in our Milky Way galaxy. He does not concern himself with other galaxies, saying that we never will know one way or the other. Gribbin draws on the work of many scientists to demonstrate the astronomically small odds of life being found elsewhere in the Milky Way galaxy. However, he concentrates on two impacts thought to have occurred between Earth and other celestial objects for his main argument.
In the first, the Earth ultimately gains its moon, the tides and the tilt that gives the seasons. The second was responsible for the Cambrian biological explosion that Gribbin contends fueled the unique circumstances that gave rise to terrestrial life. The odds of this happening anywhere else in the Milky Way are all but nonexistent.
Anyone interested in the chances of life somewhere in Earth’s neighborhood should read this book.
Focus on the Planets
Mercury returns to the evening sky the last week of February. On Feb. 22, look to the western horizon about a half hour after sunset for Mercury with a very thin crescent moon to its immediate right and Venus glittering far to its upper left.
Venus shines on the western horizon about an hour after sunset and climbs higher as the days pass. Venus sets about 8:30 p.m. as the month opens and around 9:30 p.m. as it closes.
Mars rises in the southeast about 9 p.m. and continues to gain in both size and brightness as the month progresses. The moon is to the right, and slightly lower than Mars on the 9th of the month. Mars is near its peak brilliance and details such as the north polar cap will be visible by telescope.
Jupiter is the second brightest object in the night sky and is unmistakable blazing in the west. Details such as the planet’s belts and zones, plus the dance of its moons around and across the face of Jupiter, may be readily seen by telescope.
Saturn rises in the east around midnight and two hours earlier by month’s end. The ring system is nearly open to maximum and offers a spectacular view, as does the major moon Titan that orbits the planet twice a month.
Uranus is seen as a blue-green disk in the same field of view as Venus.
Neptune is lost in the glare of the sun during February.
1 Sunrise, 6:55 a.m.; sunset, 4:43 p.m.
2 Candlemas or Groundhog Day. This is a cross-quarter day halfway between the winter solstice and spring equinox.
7 Full moon, 4:55 p.m. The full moon of February is known variously as the Snow Moon, Hunger Moon or Wolf Moon.
9 Mars is just to the upper left of the moon looking like an orange star.
11 The moon is at perigee or closest approach to Earth today.
14 Moon in last quarter, 12:05 p.m. Happy Valentine’s Day!
15 Antares the bright star of Scorpius is just below the moon at first light.
17 The sun enters Aquarius on the ecliptic.
19 The sun enters the astrological sign of Pisces, however, astronomically has just entered Aquarius.
21 Shrove or Fat Tuesday before the beginning of Lent. New moon, 5:36 p.m.
25 Look to the west just after dark for the crescent moon snuggled up to Venus while Jupiter lurks far to the upper left.
27 The moon is at apogee or farthest distance from Earth.
29 Leap day. The day added to February roughly every four years in order to bring the calendar year into a fairly close approximation with the true tropical or seasonal year. Sunrise, 6:15 a.m.; sunset, 5:22 p.m.
Send astronomical queries to Clair Wood at firstname.lastname@example.org or care of the Bangor Daily News, Style Desk, P.O. Box 1329, Bangor 04402.