Astonomy Highlights 2016
Every year Bishop Museum’s J. Watumull Planetarium (Honolulu Hawai‘i) provides a calendar of astronomical events specifically for Hawaii’s location and time zone.
Most sources that list the times for moon phases, meteor shower peaks, the start of the seasons and other events provide that information in Universal Time (UT), which is ten hours ahead of Hawaiian time. For exa.m.ple, spring 2016 starts on March 20 at 04:31 Universal Time, but starts on March 19, 6:31 p.m. Hawai‘i Standard Time.
In addition, there are certain celestial events that are specific to Hawai‘i. These include the date of Makahiki (Hawaiian New Year), which is determined by the first visible sliver of a moon after the new moon after the rising of the Pleiades at sunset (which occurs on November 17 each year).
This calendar also provides the dates and times for ‘Lāhaina Noon’ for many locations in the islands. Lāhaina Noon is the term for the two days each year when the sun is exactly overhead. This only occurs in the tropics, and the dates vary depending on latitude. Since all of main Hawaiian Islands are below the tropic of Cancer, all of them have two ‘overhead sun’ days a year.
In addition this yearly overview, Bishop Museum provides star maps for each month of the year for Hawaii’s latitude, and a monthly article (“Skywatch”) that covers the astronomical highlights of the Hawaiian night sky for each month. These resources are available at the Bishop Museum Planetarium website:
Earth at perihelion. This occurs at 1 p.m. January 2 Hawai‘i Standard Time, or at 23:00 hours on January 2 in Universal Time. (Universal Time, or ‘what time it is in England,’ uses the 24 hour clock.) On this day, the earth is only 91.5 million miles from the sun, compared an average distance of 93 million miles. (At aphelion, in July, earth is 94.5 million miles from the sun).
Like all planets, the earth’s orbit is not a perfect circle but rather an oval. Earth reaches perihelion, its closest approach to the sun, in early January each year. Some people think that the change in the seasons is due to how close we are to the sun. However, what really matters here is the tilt of the earth. Each January, while we are closer to the sun than at any other time of the year, the northern hemisphere is tilted away from the sun, and so we experience winter.
January 8 and 9 (predawn)
Closest gathering in ten years of the planets Venus and Saturn
Venus is the brightest dot in the sky, and rises in the east at 4:30 a.m. on the mornings of January 8 and January 9. On these two mornings, the planet Saturn will be less than 1/3 of a degree apart from Venus in the morning sky, less than the width of the moon. Saturn shines at 0.5, as bright as a bright star but nowhere as bright as Venus. On the morning of January 8 Venus will appear just above Saturn; on the 9th, Venus will appear just below Saturn. Day breaks around 6:30 a.m. in the Hawaiian Islands in January, so you’ll have two hours to catch this gathering.
Late January – late February 2016:
Rare chance to see all five naked-eye planets in the morning sky at one time
When Mercury returns to the morning sky around January 20, 2016, there will be about a month where all five naked-eye planets will be visible at the sa.m.e time. Looking towards the east around 6 a.m., look for blazing Venus near the east horizon; tucked below it is Mercury. High above Venus is Saturn. Mars will be about halfway up in the south, and Jupiter will be partway up in the west. Mercury lingers in the morning sky for about a month, down below Venus all the while, so you have till about February 20 to see these five planets at a single moment.
Chinese New Year
Chinese New Year occurs two new moons before the first day of spring, which occurs on March 20 this year.
Leap Day. Because it takes 365.25 days for the earth to orbit the sun, not just 365 days exactly, we need to insert an added day into the calendar every four years, or our seasons would get way of out whack with our calendar days.
We will have a deep partial solar eclipse in the Hawaiian Islands on the afternoon on March 8, 2016. At 4:33 p.m. on that day, using safe viewing techniques, you will see the sun start to be blocked out as the moon moves in front of the sun. At the peak of the eclipse, at 5:37 p.m. Hawai‘i Standard Time, 70 per cent of the sun’s disc will be blocked by the moon. At the time, the sun will be pretty low in the sky, 14 degrees (the width of one and a half of your hands, held at arm’s length) above the west horizon. The eclipse ends at 6:33 p.m. HST, just a few minutes before the sun sets at 6:36 that evening.
The timings of this eclipse are same across the Hawaiian islands, although the sunset times will be different if course. For example in Kona, Hawai‘i the eclipse starts at 4:33 p.m. and reaches it maximum coverage at 5:37 p.m., as it does in Honolulu; however, since the sun sets a little earlier in Kona than Honolulu, the eclipse will still be (barely) underway as the sun sets in Kona that night at 6:31 p.m. Lī‘hue, on the other hand, sunset is not till 6:42, so nearly ten minutes after the eclipse ends.
It is never safe to view a partial solar eclipse directly; the safe viewing glasses carried by Bishop Museum’s Shop Pacifica and other venues are a good means of viewing solar eclipses. It is also essential this time around to have a clear view of the west, since the eclipse will occur when the sun is low in the afternoon sky.
This March 8 eclipse will be total in the ocean between the main Hawaiian Islands and the Northwestern Hawaiian Islands; the path of totality will pass just south of Midway, and will not cross any of the actual islands. That said, this does make the March 8 eclipse the first total eclipse of any US state since the last solar eclipse over Hawaii in 1991!
This eclipse is also total over much of Indonesia, including the southern parts of both Borneo and Sumatra.
Jupiter in opposition; rises at sunset, overhead at midnight, sets at dawn.
Start of Daylight Saving Time for most of continental US and Canada. As of this day, the east coast is six hours ahead of the Hawaiian Islands and the west coast is three hours ahead of Hawai‘i. The Hawaiian Islands do not observe Daylight Saving Time.
Spring begins at 6:31 p.m. Hawai‘i Standard Time on March 19 (04:31 on March 20 Universal Time). This is an early start for spring, since it occurs a mere three weeks after the inserted leap day of February 29, 2016. Inserting that extra day into the calendar, as we do every four years, means that those repeating solar events, like equinoxes and solstices, all occur a little earlier than normal.
Penumbral Lunar Eclipse
Technically “visible” from Hawaii but this is of academic interest only there is no observable change in moon’s brightness or color.
There are no total or partial eclipses of the moon at all in 2016. Total and partial lunar eclipses are beautiful sights. In a total eclipse of the moon, the entire moon goes into the earth’s dark inner shadow (the “umbra”), and the moon turns black or dark red. In a partial eclipse of the moon, part of the moon is in the umbra, and it looks like a bite has been taken out of the full moon.
In a penumbral eclipse, on the other hand, no part of the moon goes into the dark inner shadow of the earth. The moon moves only into the outer shadow of the earth, missing the dark inner shadow of the earth entirely. This outer shadow, called the “penumbra,” gives it na.m.e to this flavor of lunar eclipse. During a penumbral eclipse, you will see virtually no change in the moon’s brightness; the outer shadow of the earth is too faint to darken the lunar disc. This can’t be stressed enough: PENUMBRAL LUNAR ECLIPSES ARE NON-EVENTS. You will see no change in the brightness or color of the moon during a penumbral lunar eclipse.
That said, in terms of knowing the timing: this penumbra eclipse starts at 11:39 p.m. on March 22 HST, and ends at 3:54 a.m. on March 23 HST. The “deepest” moment occurs at 1:47 a.m. on March 23 HST (11:47 on March 23 Universal Time), when about 3/4th of the moon is in the earth’s penumbra.
While I use term somewhat ironically, the entire Pacific region will “see” this non-event on the evening of March 22-23.
April 15 – end of May 2016: Mars at its peak
Mars, which shone very feebly (1.7 magnitude) when it returned to our skies in late summer 2015, will shine more brightly in spring 2016 than at any time since 2005. The red planet shines at minus 1 magnitude as of mid-April 2016 and should look very striking in evening skies. In mid-April, look for Mars rising in the east at 10 p.m. HST, is due south at 3:30 a.m. and partway down the western sky at daybreak.
Mars hits peak brightness on May 22, 2016, when it shines at minus 2.1. This is roughly the magnitude of Jupiter, usually the sky’s second-brightest dot. Mars is actually in opposition on that day of May 22. When a planet is in opposition, there is a straight line between the sun, the earth in the middle, and the planet. During opposition, a planet rises at sunset, is high at midnight and sets at dawn, as Mars will do in late May 2016. Usually an out planet shines at its brightest at opposition, as Mars does on the 22nd of May.
Easter Sunday. The Sunday after the first full moon after the first day of spring.
Transit of Mercury
Mercury moves across the face of the sun about 15 times per century, always in May or November. The most recent transit visible in the islands were on May 2006 and November 1999.
In Hawai‘i Standard Time, this transit begins at 1:15 a.m. on May 9, of course hours before the sun rises and before we can see the transit. On that day, in fact, Mercury will already be 2/3 of its way across the face of the sun when the sun rises at 6:05 a.m. in Honolulu. Using a safe viewing technique, Mercury will appear as a tiny black dot in the middle of the sun’s disk. This transit takes well over seven hours, and we will in fact still have 2.5-plus hours to observe the transit (again with safe viewing equip.m.ent) till the transit ends at 8:40 a.m. HST.
All of North and South America, Europe and Africa will see at least part of this transit. It will be visible in India and central Asia but is not visible in Korea, Vietna.m., Japan and eastern China. Also, not visible from Australia, New Zealand, Indonesia and Malaysia. The rest for the world can see this phenomenon, weather and a good solar filter permitting.
Mercury is a tiny speck against the sun’s disk, and you’ll need a telescope with a good solar filter to view it.
Saturn in Opposition
As with Mars in late May, Saturn shines at its brightest as it hits opposition on June 3. There is a straight line between sun, earth and Saturn; the ringed planet rises at sunset, is overhead all night, sets at dawn, and shines at its brightest, as exactly 0 magnitude.
Earth at aphelion, furthest point from the sun in the earth’s yearly orbit.
Summer begins on June 20 at 12:35 a.m. Hawai‘i Standard Time (22:35 on June 20 Universal Time). This is the longest day for the northern hemisphere and the shortest for the southern hemisphere.
Annular solar eclipse
(NOT VISIBLE IN HAWAI‘I)
An annular solar eclipse occurs when the moon crosses the solar disk at a point in the moon’s orbit where the moon is further than average from the earth. Being a little further away than normal, the moon is a little smaller than normal, and not large enough to block out the sun’s disc even when the moon is dead-center in the middle of the sun’s disc. So, a ring of sunlight shines around the moon (‘annulus’ comes from the Latin word for ‘ring’).
As long as any sunlight shows around the moon, there is not the awesome sense of the earth going dark in the middle of the day; in fact, an annular eclipse can occur overhead without people noticing it.
The path of the annular eclipse moves south-central Africa. Nations in the path of annularity include Gabon, the Congo, the Democratic Republic of Congo, Tanzania, and Moza.m.bique. It will also pass over the islands of Madagascar and Reunion.
As with a total eclipse, the areas for thousands of miles on each side of the annular eclipse will see a partial eclipse. Unique to this eclipse: only Africa will see any portion of this eclipse, and all of Africa will see some degree of a partial eclipse.
The peak of the annular eclipse occurs at 9:06 Universal Time on September 1, which is 11:06 p.m. on August 31 Hawai‘i Standard Time; but again this event will not be visible at all in the Hawaiian Islands, since it occurs when it’s the middle of the night in the islands.
Penumbral Lunar Eclipse
NOT VISIBLE IN HAWAII
In what continues to be a poor year for lunar eclipses, the second lunar eclipse of 2016 is also penumbral, and is not ‘visible’ in Hawaii at all. (You would need superhuman vision, that said, to tell the difference between a penumbral lunar eclipse and a normal full moon.)
This one occurs over the Indian Ocean; the peak time is 18:54 Universal Time on September 16. This is 8:54 a.m. on the 16th Hawaii Standard Time, which means we won’t see this penumbral eclipse for two reasons. 1: it occurs during the day in Hawai‘i when the moon is below the horizon. 2) You can’t see penumbral eclipses anyway.
Autumn begins at 4:22 a.m. on September 22 Hawai‘i Standard Time (14:22 Universal Time on September 22.)
First of three full moon ‘supermoons’ in a row. The moon will be a little closer to earth than average for a full moon, and thus will be a little bigger and brighter than the norm.
A moon is officially ‘full’ when the sun, earth and moon are in a straight line, with the earth in between the two other celestial bodies.
Supermoon background: the term ‘supermoon’ is a recent invention and has received a fair a.m.ount of media attention in the last few years. The term has come to refer to a full moon that occurs when the moon is near its closest point to earth in its slightly oval path around our planet. Since the moon’s path is oval, or elliptical, it can be as close as 225,600 miles from us or as far as 252,000 miles. When the moon is at the closest point to earth in its monthly path around the earth it is said to be at ‘perigee.’ A supermoon is a just a full moon that occurs in the sa.m.e day that the moon is at perigee. Since it’s a little closer than usual, the moon appears a little large than a ‘normal’ full moon.
The astrologer who coined the term ‘supermoon’ actually uses the term in reference to both new moons and full moons that occur near perigee. That said, there has been very little interest is ‘super new moons’ since you cannotsee a new moon.
Second supermoon of 2016; the moon is full at 3:52 a.m. on November 14 HST. At that time, there is a straight line between sun, earth and moon. The term supermoon just refers to a full moon that occurs when the moon is within one day of ‘perigee,’ the moon’s closest approach to earth in its monthly orbit. The moon, being a little closer than average, will be a little brighter and a little bigger.
Daylight Saving Time ends at 2 a.m. for most of continental US and Canada. As of this day, the east coast is five hours ahead of the Hawaiian Islands and the West Coast is two hours ahead.
Closest full moon of the year; the phenomenon sometimes referred to as a “supermoon.”
Makahiki (start of the Hawaiian year). To mark the start of the Makahiki season: 1) wait for the star cluster of the Pleiades to rise at sunset, which occurs every year on November 17; 2) wait for the new moon that follows this sunset rising of the Pleiades, which occurs in 2016 on November 29; 3) wait for the first visible crescent moon that follows this new moon. This year, this slender crescent should be visible in the west at dusk on December 1, thus marking the start of the Makahiki season and of the Hawaiian year.
Winter starts at 12:45 a.m. Hawai‘i Standard Time on December 21 (10:45 Universal Time on December 21).
For all meteor showers, the viewing will be better after midnight. These repeating annual events are caused as the earth enters into debris left over from a specific comet (or, in the case of the Geminids, an asteroid). As the earth goes around the sun, our planet runs into the sa.m.e debris at the sa.m.e time each year. This is why these showers occur at the same time each year. After midnight, the part of the earth that you are on is facing toward the debris that causes the meteor shower. This is why all meteor showers are better after midnight.
Meteor star showers are named for the constellation where the meteors appear to come from. The Lyrid shower in na.m.ed for Lyra, the harp, for exa.m.ple. (The Quadrantid Shower refers to an old constellation called Quadrans Muralis, which is now part of Bootes). Generally these constellations are rising in the east during the prime post-midnight viewing time for a shower. That said, don’t just look east – scan the entire sky for shooting stars.
To view shooting star showers, just find a dark location (as little city light as possible) and get comfortable (a lawn chair is a good idea).
More on meteor showers:
Quadrantid Meteor shower
Peak night: January3-4, 2016
The Quadrantids have a sharp, short peak, lasting only a few hours.
If you want to try your luck, the best viewing should be in the predawn hours on January 3 (i.e. really early on January 3, from 12:01 a.m. till dawn) and during the predawn hours January 4 (again from 12:01 a.m. ‘til dawn). There shouldn’t be much interference from the waning crescent moon, which rises around 2:30 a.m. on January 4.
The streaks of the Quadrantids appear to come from the constellation of Bootes the Herdsman, in the northeast. “Quadrant Muralis,” or “Mural Quadrant,” an old na.m.e for part of the constellation of Bootes. This was one of the now-lost constellations that were done away with when the International Astronomical Union divided the sky into 88 officially-recognized constellations in 1922.
Lyrid Meteor Shower
Best viewing times: 21:01 a.m. to dawn on April 21 and on April 22
The best viewing times for the Lyrids will be from 12:01 a.m. to dawn early on April 21, and from 12:01 a.m. to dawn early on April 22, Hawai’i Standard Time. The shower is active from April 16 – 25. While not one of the strongest showers, the Lyrids can produce up to twenty meteors per hour. On the prime viewing mornings of April 21 and 22, 2016, the moon is either full or near-full, making it the worst shower of the years in terms of moonlight. (Not only is the full moon bright, it’s up all night.) The Lyrids come from the debris of Comet C/1861 G Thatcher.
Eta Aquarid Shower
Peak: evening of May 5-6, 2016. The portion of Aquarius where the shoot stars radiate rises above the horizon around 3:45 a.m. This is a light shower, 10 to 30 meteors or so per hour when viewed from the northern half of our planet. One claim to fame: this shower is one of two showers caused by debris from Halley’s Comet, along with the Orionids in October. There is no lunar interference this year, a big plus.
Perseid Meteor Show
Peak: early in the morning on August 12, from 12:01 a.m. till dawn; and again early in the morning of August 13, 12:01 a.m. till dawn.
The Perseids are the most fa.m.ous meteor shower, with up to 80 per hour. Since the moon is waxing gibbous during this shower’s peak, it sets by 1 a.m. on August 12 and before 2 a.m. on August 13, right as the shower starts picking up. The Perseids often leave long trails. The shower is generated by debris from Comet 109 P Swift Tuttle. This comet takes 130 years to orbit the sun, and passed through the earth’s part of the solar system back in 1992, leaving lots of fresh comet debris that led to particularly good showers.
Orionid Meteor Shower
Peak: night of October 21-22; the night of October 20-21 should also be good. Active period: October 15-25. Like the Eta Aquarids in May, this one is caused by debris from Halley’s Comet. Up to 20-25 meteors per hour. Poor lunar conditions, that said, due to waning gibbous moon in the sky right as the shower peaks.
Leonid Meteor Shower
Peak: Nights of November 16-17 and 17-18; active period is November 13 – 20. The Leonids have an intense peak every 33 years and were responsible for the greatest meteor shower over Hawai‘i in recent times, the 2001 shower. Prior to that 2001 spectacle, the 1966 shower was one of the greatest on record.
Don’t expect anything like those shows till the end of our century that said, especially since this shower, like all three of the late-2016 showers, has interference from the moon.
Geminid Meteor Shower
Peak: nights of December 12-13 and 13-14, from 12:01 a.m. to dawn each night. Active period: December 6 – 19. One of the best showers; and we in Hawai‘i often have good weather in December to see it. This meteor shower is a rarity in that it is caused by debris from an asteroid (3200 Phaethon) rather than by comet debris. Conditions are a challenge this year due to full moon interference.
In the tropics the sun passes overhead twice during the year. On these two days, at local noon, the sun will be exactly overhead and an upright object such as a flag pole will have no shadow. This phenomenon only occurs in the tropics; the sun is never overhead in any other part of the planet. The northern reaches of the Hawaiian Islands, such as Midway Island, are north of the tropics and do not experience the overhead sun.
The ‘overhead sun’ date varies depending on how far north or south you are in the tropics. Thus, for Līhu‘e on Kaua‘i, this occurs on July 11, at 12:42 p.m. Further south, on the Island of Hawai‘i, the overhead sun date occurs on July 24 (12:26 p.m. for Hilo, 12:30 p.m. for Kailua Kona).
Here in the islands a term we often use for zenith noon is “Lāhaina Noon.” This is a modern term, selected by Bishop Museum in a 1990 contest held to select a na.m.e for the zenith noon phenomenon. The term “Lā haina” means ‘cruel sun’ in Hawaiian, and while the sun in the islands is almost never cruel, it can be pretty intense as it shines directly down from the zenith.
Another phrase that one hears in Hawai‘i for the zenith sun is “kau ka lā i ka lolo,” which translates as “the sun rests on the brains.” This expression is discussed in the book 1972 book Nānā I Ke Kumu (Pukui et. al.) as being a “phrase designating high noon; the time when ‘the sun is directly overhead and the shadow retreats into the body’… In view of all this, what we now call ‘high noon’ was thought to be a time of great mana (spiritual power).” While this passage has be cited by some writers to suggest that “kau ka lā i ka lolo” is thus the traditional Hawaiian term for the ‘zenith sun,’ the phrase seems to refer to “high noon” on any day, and not specifically to those two days a year when the sun is exactly overhead. Thus, in Honolulu on May 26 at 12:28 p.m., one can certainly use the term “kau ka lā i ka lolo” to describe the sun’s position as it sits exactly overhead. However, that same expression “kau ka lā i ka lolo “can be used to describe the sun’s position on any other day at local noon (at least for the non-winter months, when the sun is quite high in the sky at local noon), and does not specifically refer to the phenomenon of ‘zenith noon’ itself.
The chart below gives the overhead sun dates for a number of locations.
2016 Lāhaina Noon days and times
|Līhue||May 30 12:35 p.m.||July 11 12:42 p.m.|
|Kāne‘ohe||May 27 12:28 p.m.||July 15 12:37 p.m.|
|Honolulu||May 26 12:28 p.m.||July 15 12:37 p.m.|
|Kaunakakai||May 25 12:25 p.m.||July 16 12:34 p.m.|
|Lāna‘i City||May 23 12:24 p.m.||July 18 12:34 p.m.|
|Lahaina||May 24 12:23 p.m.||July 18 12:33 p.m.|
|Kahului||May 24 12:22 p.m.||July 18 12:32 p.m.|
|Hana||May 23 12:20 p.m.||July 18 12:30 p.m.|
|Hilo||May 18 12:16 p.m.||July 24 12:27 p.m.|
|Kailua-Kona||May 18 12:20 p.m.||July 24 12:30 p.m.|
|South Point Island of Hawai‘i||May 15 12:19 p.m.||July 28 12:28 p.m.|
|New Moon||First Quarter||Full Moon||Third Quarter|