Come Thursday (March 19), we will have a change of the seasons: the occurrence of the vernal equinox, marking the official start of spring in the Northern Hemisphere and autumn in the Southern Hemisphere. In fact, it will be a rather auspicious occurrence: the earliest that the equinox has occurred nationwide in 124 years. More on that in a moment.
The exact moment of the equinox will occur Thursday night at 11:49 p.m. EDT (0349 GMT on March 20), according to the astronomy reference book “Astronomical Table of the Sun, Moon and Planets” (Willmann-Bell, 2016). At that time, the Earth will reach the point in its orbit where its axis isn’t tilted toward or away from the sun. Thus, the sun will then be directly over a specific point on the Earth’s equator moving northward. On the sky, it’s where the ecliptic and celestial equator cross each other.
This image of Earth was captured during the spring equinox in 2011 by the Spinning Enhanced Visible and Infrared Imager (SEVIRI) on the Meteosat-9 satellite. (Image credit: NASA)
A not-so-equal equinox
On the day of the equinox, the sun will appear to rise exactly east and set exactly west. Daytime and nighttime are often said to be equally long with the equinox, but this is a common misconception — the day can be up to 8 minutes longer, depending on your latitude.
The sun is above the horizon half the day and below for half — but that statement neglects the effect of the Earth’s atmosphere, which bends the rays of sunlight (called refraction) around the Earth’s curvature when the sun lies close to the horizon. But, because of this bending of the sun’s rays, the disk of the sun is always seen slightly higher above the horizon than it really is.
In fact, when you see the sun appearing to sit on the horizon, what you are looking at is an optical illusion; the sun at that moment is actually below the horizon. So, we get several extra minutes of daylight at the start of the day and several extra minutes more at the end.
The supposed equality of day and night gives us the Latin name “equinox,” which means “equal night.” But in reality, thanks to our atmosphere, the day is longer than the night at the equinox. At the latitude of New York, for instance, day and night are roughly equal a few days before the equinox, on St. Patrick’s Day (March 17).
Sun overhead from the Emerald of the Equator
Astronomers can calculate the moment of the vernal equinox right down to the nearest second. This year it will occur on Thursday (March 19) at 11:49:28 p.m. EDT (0349 GMT on March 20). At that moment, the sun will appear directly overhead about 50 miles (80 kilometers) south of Gorontalo, a province of Indonesia — often referred to as the “Emerald of the Equator” — on the island of Sulawesi, on the equator in the Gulf of Tomini. In the days that follow, the direct rays of the sun migrate to the north of the equator and the length of daylight in the Northern Hemisphere will correspondingly appear to increase.
Why so early?
As was noted, this will be the earliest that the vernal equinox will occur across the contiguous United States in 124 years. There are two specific reasons for this variation of the date: leap years and daylight saving time.
When a leap year set us back a day
First, that 2020 is a leap year (meaning that the month of February had one extra day) is not the reason for the early arrival of this year’s equinox. Rather, it is the leap year that we observed in the year 2000.
Let’s look at the dates and times of the vernal equinoxes leading up to 2000. Note that each year the occurrence of the equinox happens about 6 hours (or one-quarter of a day) later in the calendar:
1996: March 20 at 3:03 a.m. EST (0803 GMT)
1997: March 20 at 8:54 a.m. EST (1354 GMT)
1998: March 20 at 2:54 p.m. EST (1954 GMT)
1999: March 20 at 8:46 p.m. EST (0146 GMT on March 21)
2000: March 20 at 2:35 a.m. EST* (0735 GMT)
In 46 B.C., Julius Caesar’s consulting astronomer, Sosigenes, knew from Egyptian experience that the solar year was about 365.25 days in length. So to account for that residual quarter of a day, an extra day — leap day — was added to the calendar every four years. Unfortunately, the new Julian calendar was 11 minutes and 14 seconds longer than the actual solar year. By the year 1582 — thanks to the overcompensation of observing too many leap years — the calendar had fallen out of step with the solar year by 10 days.
It was then that Pope Gregory XIII stepped in and, with the advice of his own astronomer, Christopher Clavius (1538-1612), produced our current “Gregorian” calendar. First, to catch things up, 10 days were omitted after Oct. 4, 1582, making the next day Oct. 15. In order to better adjust the new calendar format to more closely match the length of the solar year, most century years (such as 1700, 1800, 1900) — which in the old Julian calendar would have been observed as leap years — were not. The exceptions were those century years equally divisible by 400. That’s why 1700, 1800 and 1900 were not leap years.
But 2000 was a century year, evenly divisible by 400, so it was observed as a leap year. Had we skipped the leap year in 2000 (as in 1900), then the vernal equinox in 2000 would have occurred a day later, on March 21 at 2:35 a.m. EST (0735 GMT).
Hence, the reason we have an asterisk next to that date.
So, thanks to February having an extra day in 2000, the date of the equinox slipped back a day to March 20.
Daylight saving time delayed the equinox in the East
Because the solar year is not exactly one-quarter of a day longer than the 365-day calendar year, but a little bit less than one-quarter (24.22%) of a day, the occurrence of the equinox comes about 47 minutes earlier (on average) every four years:
2000: March 20 at 2:35 a.m. EST (0735 GMT)
2004: March 20 at 1:48 a.m. EST (0648 GMT)
2008: March 20 at 1:48 a.m. EDT (0548 GMT)*
2012: March 20 at 1:14 a.m. EDT (0514 GMT)
2016: March 20 at 12:30 a.m. EDT (0430 GMT)
2020: March 19 at 11:49 p.m. EDT (0349 GMT on March 20)
The asterisk (*) indicates that the United States and Canada had begun observing daylight saving time on the second Sunday in March rather than the first Sunday in April, a practice that began in 2007. In 2000, only those in the Pacific time zone (as well as in Alaska and Hawaii) observed the equinox on March 19. In 2004, 2008 and 2012, those time zones again saw spring arrive on March 19, along with people on Mountain Time.
In 2016, those in the Central time zone celebrated a March 19 arrival. Were we still on the old system (when daylight saving time did not begin until early April), we would have been on standard time in 2016, and those in the eastern parts of North America, too, would have observed the equinox on March 19 (at 11:30 p.m. EST), but daylight time pushed that off for another four years. Finally this year, from coast-to-coast, spring will arrive on March 19 — the earliest in 124 years.
And as a point of record: In 1896, the vernal equinox arrived on March 19 at 9:29 p.m. EST (0229 GMT on March 20).
Astronomical vs. meteorological spring
Truth be told, there are really two springs: astronomical spring and meteorological spring.
Astronomical spring is measured by the vernal equinox, but that’s only a marker in the big flow of time, set up by astronomers — a sidereal milepost, accurate as a ticking clock but only approximately timing the changing of the seasons.
Meteorological spring supposedly has already started as of March 1, and runs through the end of May, according to Accuweather. In truth, however, meteorological spring ignores the clock and calendar, makes its own rules and creates a festival of song and blossom, all in its own time.
The crocuses, early robins and other vernal phenomena pay no attention to the hairsplitting details marking the astronomical arrival of the vernal equinox. They all have their own way of knowing when spring truly begins.
TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.
Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.
Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.
The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.
The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.
It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.
Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.
Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.
Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.
Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.
Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.
The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”
VICTORIA – The British Columbia government is partnering with a bear welfare group to reduce the number of bears being euthanized in the province.
Nicholas Scapillati, executive director of Grizzly Bear Foundation, said Monday that it comes after months-long discussions with the province on how to protect bears, with the goal to give the animals a “better and second chance at life in the wild.”
Scapillati said what’s exciting about the project is that the government is open to working with outside experts and the public.
“So, they’ll be working through Indigenous knowledge and scientific understanding, bringing in the latest techniques and training expertise from leading experts,” he said in an interview.
B.C. government data show conservation officers destroyed 603 black bears and 23 grizzly bears in 2023, while 154 black bears were killed by officers in the first six months of this year.
Scapillati said the group will publish a report with recommendations by next spring, while an independent oversight committee will be set up to review all bear encounters with conservation officers to provide advice to the government.
Environment Minister George Heyman said in a statement that they are looking for new ways to ensure conservation officers “have the trust of the communities they serve,” and the panel will make recommendations to enhance officer training and improve policies.
Lesley Fox, with the wildlife protection group The Fur-Bearers, said they’ve been calling for such a committee for decades.
“This move demonstrates the government is listening,” said Fox. “I suspect, because of the impending election, their listening skills are potentially a little sharper than they normally are.”
Fox said the partnership came from “a place of long frustration” as provincial conservation officers kill more than 500 black bears every year on average, and the public is “no longer tolerating this kind of approach.”
“I think that the conservation officer service and the B.C. government are aware they need to change, and certainly the public has been asking for it,” said Fox.
Fox said there’s a lot of optimism about the new partnership, but, as with any government, there will likely be a lot of red tape to get through.
“I think speed is going to be important, whether or not the committee has the ability to make change and make change relatively quickly without having to study an issue to death, ” said Fox.
This report by The Canadian Press was first published Sept. 9, 2024.
The European Space Agency is fast-tracking a new mission called Ramses, which will fly to near-Earth asteroid 99942 Apophis and join the space rock in 2029 when it comes very close to our planet — closer even than the region where geosynchronous satellites sit.
Ramses is short for Rapid Apophis Mission for Space Safety and, as its name suggests, is the next phase in humanity’s efforts to learn more about near-Earth asteroids (NEOs) and how we might deflect them should one ever be discovered on a collision course with planet Earth.
In order to launch in time to rendezvous with Apophis in February 2029, scientists at the European Space Agency have been given permission to start planning Ramses even before the multinational space agency officially adopts the mission. The sanctioning and appropriation of funding for the Ramses mission will hopefully take place at ESA’s Ministerial Council meeting (involving representatives from each of ESA’s member states) in November of 2025. To arrive at Apophis in February 2029, launch would have to take place in April 2028, the agency says.
This is a big deal because large asteroids don’t come this close to Earth very often. It is thus scientifically precious that, on April 13, 2029, Apophis will pass within 19,794 miles (31,860 kilometers) of Earth. For comparison, geosynchronous orbit is 22,236 miles (35,786 km) above Earth’s surface. Such close fly-bys by asteroids hundreds of meters across (Apophis is about 1,230 feet, or 375 meters, across) only occur on average once every 5,000 to 10,000 years. Miss this one, and we’ve got a long time to wait for the next.
When Apophis was discovered in 2004, it was for a short time the most dangerous asteroid known, being classified as having the potential to impact with Earth possibly in 2029, 2036, or 2068. Should an asteroid of its size strike Earth, it could gouge out a crater several kilometers across and devastate a country with shock waves, flash heating and earth tremors. If it crashed down in the ocean, it could send a towering tsunami to devastate coastlines in multiple countries.
Over time, as our knowledge of Apophis’ orbit became more refined, however, the risk of impact greatly went down. Radar observations of the asteroid in March of 2021 reduced the uncertainty in Apophis’ orbit from hundreds of kilometers to just a few kilometers, finally removing any lingering worries about an impact — at least for the next 100 years. (Beyond 100 years, asteroid orbits can become too unpredictable to plot with any accuracy, but there’s currently no suggestion that an impact will occur after 100 years.) So, Earth is expected to be perfectly safe in 2029 when Apophis comes through. Still, scientists want to see how Apophis responds by coming so close to Earth and entering our planet’s gravitational field.
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“There is still so much we have yet to learn about asteroids but, until now, we have had to travel deep into the solar system to study them and perform experiments ourselves to interact with their surface,” said Patrick Michel, who is the Director of Research at CNRS at Observatoire de la Côte d’Azur in Nice, France, in a statement. “Nature is bringing one to us and conducting the experiment itself. All we need to do is watch as Apophis is stretched and squeezed by strong tidal forces that may trigger landslides and other disturbances and reveal new material from beneath the surface.”
The Goldstone radar’s imagery of asteroid 99942 Apophis as it made its closest approach to Earth, in March 2021. (Image credit: NASA/JPL–Caltech/NSF/AUI/GBO)
By arriving at Apophis before the asteroid’s close encounter with Earth, and sticking with it throughout the flyby and beyond, Ramses will be in prime position to conduct before-and-after surveys to see how Apophis reacts to Earth. By looking for disturbances Earth’s gravitational tidal forces trigger on the asteroid’s surface, Ramses will be able to learn about Apophis’ internal structure, density, porosity and composition, all of which are characteristics that we would need to first understand before considering how best to deflect a similar asteroid were one ever found to be on a collision course with our world.
Besides assisting in protecting Earth, learning about Apophis will give scientists further insights into how similar asteroids formed in the early solar system, and, in the process, how planets (including Earth) formed out of the same material.
One way we already know Earth will affect Apophis is by changing its orbit. Currently, Apophis is categorized as an Aten-type asteroid, which is what we call the class of near-Earth objects that have a shorter orbit around the sun than Earth does. Apophis currently gets as far as 0.92 astronomical units (137.6 million km, or 85.5 million miles) from the sun. However, our planet will give Apophis a gravitational nudge that will enlarge its orbit to 1.1 astronomical units (164.6 million km, or 102 million miles), such that its orbital period becomes longer than Earth’s.
It will then be classed as an Apollo-type asteroid.
Ramses won’t be alone in tracking Apophis. NASA has repurposed their OSIRIS-REx mission, which returned a sample from another near-Earth asteroid, 101955 Bennu, in 2023. However, the spacecraft, renamed OSIRIS-APEX (Apophis Explorer), won’t arrive at the asteroid until April 23, 2029, ten days after the close encounter with Earth. OSIRIS-APEX will initially perform a flyby of Apophis at a distance of about 2,500 miles (4,000 km) from the object, then return in June that year to settle into orbit around Apophis for an 18-month mission.
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Furthermore, the European Space Agency still plans on launching its Hera spacecraft in October 2024 to follow-up on the DART mission to the double asteroid Didymos and Dimorphos. DART impacted the latter in a test of kinetic impactor capabilities for potentially changing a hazardous asteroid’s orbit around our planet. Hera will survey the binary asteroid system and observe the crater made by DART’s sacrifice to gain a better understanding of Dimorphos’ structure and composition post-impact, so that we can place the results in context.
The more near-Earth asteroids like Dimorphos and Apophis that we study, the greater that context becomes. Perhaps, one day, the understanding that we have gained from these missions will indeed save our planet.
