The month of January is named for the Roman god Janus, who looks into the future as he looks into the past. He’s shown with two faces. Janus is the god of beginnings, endings, transitions and passages.
The days are still very short and the nights quite long during this first full month of winter. There are five good highlights that are worth braving the cold this month to witness. In order of their dramatic impact, there’s a total lunar eclipse starting Sunday night the 20th; the best meteor shower of the year, the Quadrantids, on the 3rd; a nice conjunction of Venus and Jupiter on the 22nd; Comet Wirtanen still hanging around, now in the Big Dipper; and a potentially dangerous asteroid passing through Taurus and part of the Winter Hexagon all month.
In honor of this month’s namesake, here’s a review of the top discoveries in astronomy for the last year and a taste of what to expect in 2019.
In reverse order, the fifth greatest astronomical discovery of last year was the Gaia mission’s mapping of over a billion stars in our galaxy and millions of other galaxies. Not only were their current positions mapped, but the parallaxes and proper motions of these objects were also determined, giving us a moving, three-dimensional image of numerous stars.
The fourth one was confirming a 100-mile-high plume of water ejected from the ocean under Jupiter’s moon Europa. When the next mission to this intriguing moon, called the Europa Clipper, launches in 2023 and gets there a few years later, it can simply fly through a plume like this to sample it for any signs of life without drilling into the moon.
The third one was finding an underground lake, about 12 miles wide and at least 3 feet deep, about a mile below the surface of Mars.
The second one was finding a strange, cigar-shaped object about a half-mile long named Oumuamua, Hawaiian for “scout.” This comet came in from another solar system and even has different chemistry than comets from our solar system.
The top discovery in astronomy in 2018 was confirming that we detected about a dozen neutrinos that emanated from a galaxy 5.7 billion light years away, located in the arm of Orion. Called a blazer, this galaxy is shooting a powerful jet of material into space at nearly the speed of light. Created by material falling into the supermassive black hole at the center of the galaxy, this jet is pointing directly at us. We detected the neutrinos using a combination of different types of telescopes, called multimessenger astronomy. One of them is called IceCube, a neutrino telescope built into the ice near the South Pole.
No one can predict what we will discover this year but here are a few missions that could lead to discoveries. On the first day of the year, the New Horizons spacecraft that had a wildly successful encounter with Pluto – beyond all expectations on July 14, 2015 – will encounter its second target, a Kuiper belt object named Ultima Thule.
The first image of a black hole’s event horizon will probably be processed and released this year from the Event Horizon Telescope. NASA’s first crewed spaceflights of commercial capsules are expected to begin this spring or summer. India is slated to launch a mission that will land on the moon early this year. Japan’s Hayabusa2 is scheduled to leave the asteroid Ryugu late this year with samples that should get back to Earth in 2020.
Then the James Webb telescope should be progressing nicely towards it new launch date of March 30, 2021.
The entire country is perfectly placed to observe the total lunar eclipse that will start at 9:37 p.m. on Sunday the 20th. But nothing will really be visible until shortly before the moon enters the deeper part of Earth’s shadow, called the umbra, at 10:34. The moon will be completely immersed in our shadow by 11:41 and will spend just over an hour there, until 12:43 a.m. Then the partial phase will end about an hour later, at 1:51, and the entire eclipse won’t completely end until 2:48.
That’s the timeline of this event, but the real beauty and magic of the interaction between our three most common and obvious objects – the sun, moon and Earth, seen in a completely new way – happens as you observe carefully, along with gaining a better understanding of what’s really happening here. The coppery red color that you will slowly see the moon turn is actually the reflection of all of the sunrises and sunsets on Earth projected onto the moon all at once. Our atmosphere is bending, or refracting the sunlight around the earth and onto the moon to create a visually stunning three-dimensional image, capturing an elusive moment in time as our shadows intersect. You can even try to envision a fourth dimensional image of the constantly moving shadows of the earth and the moon. Also, try to photograph this great event as it unfolds.
The Quadrantid meteor shower will peak on the night of the 3rd into the 4th. It has a very narrow peak but you could expect up to 100 meteors per hour emanating from just below the Big Dipper. This shower is also caused by an asteroid, like the Geminids, and not a comet.
Venus and Jupiter will be just two degrees apart in the morning sky at 5 a.m. on Tuesday the 22nd. Comet Wirtanen is still visible but you will need binoculars to find it in the Big Dipper. An asteroid named 433 Eros will be closest to Earth on the 15th and visible all month in Taurus with a good pair of binoculars or a small telescope.
Then Saturn will reappear in the morning sky by the middle of the month. Mars is still the only evening planet, visible in Pisces the fish and setting around 11 p.m. each night as it moves at about the same rate we’re moving around the sun. Even though the red planet is dropping a little farther behind us each day, it still has a nice orange color and is brighter than average. The moon only looks orange right when it rises or sets or when it gets eclipsed, but Mars always looks a little orange.
JANUARY HIGHLIGHTS
Jan. 1: New Horizons will encounter a Kuiper belt object named Ultima Thule today. Ceres, the largest asteroid, was discovered on this day in 1801. The moon will pass just north of Venus this morning.
Jan. 2: Earth is at perihelion, or closest to the sun, at 91.4 million miles today.
Jan. 3: The Quadrantid meteor shower peaks tonight. The moon passes just north of Jupiter this morning.
Jan. 5: New moon is at 8:28 p.m.
Jan. 7: On this day in 1610, Galileo discovered three moons of Jupiter.
Jan. 8: Stephen Hawking was born on this day in 1942.
Jan. 12: The moon passes just south of Mars tonight.
Jan. 14: First-quarter moon is at 1:46 a.m.
Jan. 15: Venus passes Antares in Scorpius this morning.
Jan. 21: Full moon is at 12:16 a.m. There will also be a total lunar eclipse tonight visible for all of North America.
Jan. 22: Venus passes just 2 degrees north of Jupiter this morning.
Jan. 27: Last-quarter moon is at 4:10 p.m.
Jan. 30: The moon passes just north of Jupiter this morning.
Jan. 31: The moon passes very close to Venus this morning.
Bernie Reim of Wells is co-director of the Astronomical Society of Northern New England.
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