The month of April – Aprilis in Latin – likely gets its name from a word meaning opening. That is exactly what the northern hemisphere is now doing during our first full month of spring, even though we had a very mild winter.

The celestial patterns are always changing, just as the terrestrial patterns are changing with our seasons caused by Earth’s 23.5-degree tilt. Notice that Orion and the famous winter hexagon are getting lower in the west just as the equally famous summer triangle is beginning to rise in the east. It consists of Lyra the harp, Cygnus the swan and Aquila the eagle.

There are several highlights this month. These include Mercury’s best apparition of the year, Mars getting closer and brighter each day, a comet and an asteroid in Leo the lion, and the Lyrid meteor shower.

I hope you saw that wonderful total solar eclipse over Indonesia early in March. I watched a live feed and was thrilled by its continual unfoldment and its unexpected occurrences like seeing the shadow bands race across Earth faster than the speed of sound and the solar prominences visible just before and during totality.

I learned a lot about the power of our sun from the professional astronomers sharing their insights and commentary with the viewers. It was also educational to get a glimpse of life in these locations halfway around the Earth. As you physically become the fourth body in a perfect alignment of the three most important bodies in all of humanity’s life on Earth, it really shows you the enormous power of nature and the surprisingly great influence that any individual can have as they align themselves with this power and understand more about it and how to use it for the good of mankind. Just one average solar flare releases enough energy in one second to provide all the power needs of this entire country for 100 years.

This was an especially important eclipse because it helped to prepare us for our own total solar eclipse next summer, on Monday, Aug. 21. The narrow path of totality will cut right across our country from Oregon to South Carolina – the first time in nearly 100 years. It is not too early to start researching the best locations and methods of capturing and sharing this amazing and rare event. Then we will be very lucky and enjoy another total solar eclipse less than seven years later on April 8, 2024, which will pass over Maine.

Mercury makes its best showing for the year on April 18. Our first planet starts the month by rising around 7:30 p.m. By the middle of the month it will not set until 8:30 p.m. It will be 20 degrees east of the sun and it will reach 10 degrees high, or one fist at arm’s length. Watch the waxing crescent moon pass nearby on April 8. One of the best events for 2016 will be the transit of Mercury across the face of the sun on Monday, May 9.

Mars will more than double in brightness during April as Earth is rapidly catching up with its neighboring planet. Then it will continue to get brighter and larger until we get closest to it on May 22. That point is called opposition and only happens every 26 months for Mars, but about every 13 months for the other superior planets. The Red Planet is already showing some nice detail on its surface in small telescopes and it will only get better over the next several months until we pull too far ahead of it by July in our faster orbit around the sun.

Jupiter is still close to its best for the year, now rising just before sunrise. Saturn is getting closer and brighter, rising around midnight and approaching its own opposition in early June.

A comet named Ikeya-Murakami is drifting right through Leo the lion this month. Discovered in 2010, this comet will pass just half a degree below Regulus, the brightest star in Leo and the 21st brightest star in the whole sky, on April 24 and 25. It will only shine at around 10th magnitude, so you will need a telescope to see it for yourself.

There will also be an asteroid crossing through another part of Leo this month. It will glow at about the same magnitude as the comet, so you will also need at least a small telescope to see 6 Hebe, the source of 40 percent of all the meteorites that fall to Earth. It is about the eighth largest of all the millions of asteroids and its diameter is about 120 miles. It is at its closest to Earth now and is visible just above the tail of Leo.

Remember that NASA’s Dawn spacecraft is still orbiting the largest of all asteroids, named Ceres, which is about 600 miles in diameter. Dawn just visited the second largest asteroid, Vesta, a few years ago.

There is a Japanese spacecraft on its way right now to an Earth-crossing asteroid named Ryugu. The spacecraft was launched in December 2014 and should get there by 2018. It will gather several pounds of material from this asteroid and then return its precious cargo to Earth by 2020. NASA will launch OSIRIS-REx on its way to another dangerous, Earth-crossing asteroid named Bennu in September of this year. It will also return samples to Earth. By analyzing these samples, we will learn more about the origins of life on Earth and how to protect ourselves from asteroids that may hit us.

Remember that on Feb. 15, 2013, we knew that an asteroid named 367943 Duende would pass just 17,000 miles above Earth, which is closer than our many geosynchronous satellites orbit. What we didn’t expect was a 65-foot-diameter asteroid that came in from the direction of the sun and exploded just above the city of Chelyabinsk, Russia, that morning, injuring 1,500 people. Soon we will be better prepared with our new knowledge.

The Lyrid meteor shower will peak April 22, but the full moon will wash out most of these meteors, caused by Comet Thatcher, which has a 415-year orbit.


April 1: On this day in 1997, Comet Hale-Bopp made its closest approach to the sun.

April 6: The moon passes less than 1 degree north of Venus this morning.

April 7: New moon is at 7:24 a.m. EDT. The Compton Gamma Ray Observatory was launched on this day in 1991.

April 11: On this day in 1986, Halley’s Comet was closest to Earth.

April 12: On this day in 1961, Yuri Gagarin became the first human in space.

April 13: First quarter moon is at 11:59 p.m. EDT.

April 16: Mars is stationary, beginning its retrograde (westward) motion today.

April 18: The moon passes 2 degrees south of Jupiter this morning. Pluto is stationary.

April 22: Full moon is at 1:24 a.m. This is also called the Grass, Egg, Pink or Fish Moon.

April 25: On this day in 1990, the Hubble Space Telescope was deployed.

April 29: Last quarter moon is at 11:29 p.m. EDT.

Bernie Reim of Wells is co-director of the Astronomical Society of Northern New England.

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