Why Does Easter’s Date Always Change?

 

This upcoming weekend brings Easter for 2021, the one holiday wherein you have a legitimate reason to be waiting for the last minute to do your shopping for the simple reason that it has no fixed date. So, why is this?

As far as holidays go, they generally have a set date. Independence Day is always July 4 and Christmas is always December 25 (unless you’re Orthodox, then it’s January 7 for you). Another time fixing method goes for Thanksgiving, which is always the 4^th Thursday of November, meaning that, while its date changes year to year, it’s always at the end of the month. And then there’s Easter, which can float from late March to late April. So what gives?

Blame the Moon.

The formula for determining the date of Easter is as follows: Easter Sunday falls on the first Sunday after the first Full Moon after the Spring Equinox. Still, though, you may still be asking why the holiday doesn’t have a fixed date because, after all, Christ only rose from the dead on one day, which leads many to ask why we celebrate the anniversary of His rising different days every year.

Well, blame the Moon (and the historical record) again.

As hard as it is to believe today in a world where Christianity is the world’s largest religion, it was anything but 2000 years ago. Thanks to the lack of historical records, we do not know for certain the years (let alone the dates) when Jesus was born and died. The only concrete reference we have as to when Jesus died was that it is well documented that He was crucified while in Jerusalem to celebrate Passover, a Jewish holiday whose date is set by the lunar calendar.

In its first 3 centuries as an underground religion, there was no real central authority for Christians on matters of religion. Result: different churches celebrated Easter on different dates, most often either on Passover itself or the Sunday immediately after. It was not until the Roman Emperor Constantine became a Christian and made Christianity the official religion of the Roman Empire that there was uniformity on matters of religion. It was only then that Easter was fixed as the Sunday following Passover.

As for some trivia, the earliest Easter was in 1818, when the Full Moon fell on the Equinox (a Saturday), and Easter was the following Sunday, March 22. The next time this will happen: 2285. The latest Easter was in 1943, when the Full Moon was the day before the Spring Equinox, which meant that another full lunar cycle did not result in another Full Moon until Sunday, April 18, which led to an Easter on the latest possible date: April 25. This will next happen in 2038.

On top of all the date shifting, Orthodox churches use the old Julian Calendar for determining religious holidays, which means that Western and Eastern Easter often fall on different dates, as they do this year. The next time both Easters sill sync up: 2025. 

 

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What Time Is It? Time to Stop Changing the Clocks?

 

The United States has just completed its first half of the twice a year time change headache as we sprang forward an hour into Daylight Savings Time, unless you live in Hawaii or Arizona, in which there is no DST. For many people, the twice a year ritual involves a lot of complaining, forgetting, and possibly getting to a Sunday morning destination at the wrong time.

Wouldn’t it be nice if this could all just go away?

Well, in a rare show of bipartisanship, the Sunlight Protection Act has been reintroduced to the Senate as of last week. First proposed by Florida’s Republican Senator Marco Rubio, the bill would eliminate the twice a year time change by making spring forward permanent, as in putting the entire country (with a caveat-more on that later) on DST, permanently.

See also: Europe Grapples With Time Change Gripes

In a statement, Rubio called the twice a year time change “antiquated” and observed that there is increasing support for ending the time change. Rubio also said that the benefits of extended evening daylight would include less car crashes, less winter depression, and more “stability” to families.

While he probably does not agree with Rubio on much, Massachusetts Democrat Ed Markey also supports the bill, saying that year long DST could “improve public health, public safety, and mental health - especially important during this cold and dark COVID winter.”

Other signed-on sponsors of the bill are Senators James Lankford, R-Oklahoma, Roy Blunt, R-Missouri, Sheldon Whitehouse, D-Rhode Island, Ron Wyden, D-Oregon, Cindy Hyde-Smith, R-Mississippi, and Rick Scott, R-Florida.

Also speaking on the bill, Whitehouse noted that “Americans' lifestyles are very different than they were when Daylight Saving Time began more than a century ago,” before adding permanent DST will
“give families more daylight hours to enjoy after work and school.”

Both of those points are pretty hard to argue with.

On top of bipartisan support in the Senate, 15 states: Arkansas, Alabama, California, Delaware, Georgia, Idaho, Louisiana, Maine, Ohio, Oregon, South Carolina, Tennessee, Utah, Washington and Wyoming, have passed their own laws/resolutions/voter initiatives calling for permanent DST. The problem: only federal law can change/end the time change, which means that the state statutes are void without a federal go-ahead.

As for the caveat mentioned earlier, the Sunlight Protection Act would not apply to places that currently don't observe DST (Arizona and Hawaii).

On the other hand, opponents of year-long DST voice concerns about delayed daylight during the winter having the potential to cause more car crashes on the front end of the day, which also coincides with the start of the school day. On the other hand, supporters of all-year DST will argue that most schools already start their classes before sunrise (at least during winter) and it’s rare for children to be hit by motorists on the way to school even now.

Should we go permanent DST? Well, in the effort of doing something that may actually bring the country together for a change, it may be worth a go.

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How to Spot a Young (or Old) Moon Within 24 Hours of New

 

Can you find the Moon at right? Even this is over 24 hours old!

What is the thinnest crescent Moon you can see? Can you see the Moon within 24 hours of New phase? The answer to the first question will vary but the answer to the second is undeniably a 'yes' as it is very possible to see the Moon within 24 hours of New. For even better news, spring is an ideal time to look.

Young/Old Moons (within 24 hours of New) are, besides quite aesthetic, rare, very rare. To sight a Moon within 24 hours of New requires all the conditions to line up just right. If everything goes perfectly, on the day after/before New Moon (or even on the same day depending on the time of New), just past sunset/before sunrise, a wire-thin crescent will pop out low on the horizon. Needless to say, when dealing with a Moon less than 2% illuminated, binoculars are a must.

So here is why the Young/Old Moon is so difficult to spot:

1. Timing. If New Moon is timed too close to sunset/sunrise, it will be lost in the Sun's glare on the day of New Moon and will be way past the 24 hour window at its first/last visibility for the cycle. While pretty, a 36 hour Moon is no challenge, pure and simple. Look up and find it.

2. Clouds. If it's cloudy, there's no seeing the Moon. In my Northeast Ohio area, spring and fall are 50/50 odds for a clear sky, at best.

3. Light. Young/Old Moon hunters are forced to fight the Sun With the Moon under 2% lit, just the act of spotting the Moon low on the horizon in such light conditions is a challenge because that is where the Sun is. A saving grace can be a nearby planet or bright star. If you can use a bright star or planet as a marker, it is a lot easier to estimate where the Moon will appear once the sky gets dark enough.

4. Haze. Even more so than during the day, haze makes its presence known at dusk, looking similar to wispy clouds on the horizon. While the biggest problem during the summer, haze can even appear in winter, too. Even a crystal-clear day can produce haze on the horizon at dusk. While the haze will quickly dissipate come dark, that's too late for the Young Moon. As a way to estimate haze before dark, look at the daytime sky. The deeper the blue, the lower chance of haze ruining the show. The good news, come fall and Old Moon season, the haze will be long gone as dawn approaches.

5. Horizon Obstructions. Buildings and trees can play havoc with the horizon as Young/Old Moons will be within 10 degrees of it. What does that look like? Hold a fist vertical at arm’s length to simulate 10 degrees, then go outside and see how your surroundings do. Chances are, you’ll have to scout a good observation sight in advance if you live in a built-up area.

Now for the good news: spring is Young Moon season. Because of the near vertical ecliptic at sunset, the waxing Moon will hang higher in the sky now than any other time of year, which is good. For Young Moon Hunters, March through May (add February and/or June depending on time of month New Moon falls) is an ideal time to look.

On the other end of the scale, Fall is Old Moon season as the ecliptic is nearly vertical from September through November at sunrise (add August and/or December depending on New Moon’s time of month), making this the ideal time to spot an Old Moon, one within 24 hours of becoming New again.

As for this spring's Young Moon season, thin crescents will appear on March 14, April 12, May 12, and June 11. Of the four, only one will be a true Young Moon (April 12) and only for those people living in the Eastern and Central Daylight Time Zones. Mountain Time and West? The Moon will be over 24 hours old, but still worth a look as few people have ever seen a crescent that thin.

Whichever time (hopefully both!) you plan to hunt a thin Moon, give it a try it if it's clear.

In need of inspiration, here you go for some of my pictures!

A 17 Hour Young Moon (holy cow!)
A 19 Hour Moon (featured on Spaceweather’s home page)
A 23 Hour Moon

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3 Perspectives: The Great Jupiter Saturn Winter 2020 Conjunction

Tonight, the first day of winter 2020, will bring Jupiter and Saturn closer together than they have appeared in nearly 800 years, which will see the two planets separated by about a tenth of an angular degree. For comparison, a little finger held at arm’s length spans about half of a degree. The best news: this will be an event visible to the naked eye as all one has to do is look low in the Southwest about an hour after sunset. Jupiter is the brighter, lower planet and Saturn is the dimmer, higher one.

However, for some real fun, add optical aid. With binoculars of around 10x power (and held steadily or mounted on a tripod), the two objects will become six as Jupiter’s four largest moons will pop into view, appearing as tiny stars in a line around the planet. Saturn may also appear slightly oval in shape.

With a telescope, the rings of Saturn will become visible, as will the cloud bands on Jupiter. For an interesting comparison, look at the span of Jupiter’s moons as compared to the separation between the two planets. Visually, the planets will appear closer together than the most distant of the moons, although they will actually be hundreds of millions of miles distant in space.

As for what to expect, look no farther than below as the three pictures taken on Sunday, December 20 show the perspectives from naked eye (Nikon D700 and 50mm lens), binocular (200mm lens), and telescopic (600mm FL) view. 

 

 

 

Whichever way you plan to view the event, don’t miss it if its clear. Additionally, the planets will remain extremely close the next few nights if it’s cloudy, switching places along the way.

 

Way Back When . . . 

As an interesting aside, this event takes place almost exactly 14 years after another historic conjunction, which saw 3 planets, Mercury, Mars, and Jupiter, all come to within a degree of each other. Here's my photo from that event with my old Hewlett-Packard PS 945 point and shoot (yes, HP made cameras back in those days!). The photo is at 300mm equivalent.

Oh yes, I got featured (sort of) with this picture on Spaceweather, too.

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A Complete List of Weather-Resistant Tamron Lenses

Tamron markets its weather sealed lenses as “dust/moisture resistant.”

Being someone who values both high quality and saving money, I always wondered what Tamron optics were weather-sealed. Unfortunately, I haven't succeeded in finding a concise list of such lenses anywhere. So, seeing a solution rather than a problem, I decided to compile one myself. So, if you're in the same boat I was in, here you go: a concise list of weather resistant Tamron lenses, which can not only stand up to the harshest environments, but can also save the buyer a lot of money over manufacturer optics. Know someone else you think would find this useful? Why not pass it on?

Companies are quick to tout cameras for weather-resistance. Unfortunately, what most beginning dSLR users don't know is this: there might as well be no weather sealing in the camera if it doesn't have a weather-sealed lens to go with it. Why is this? Simple: the lens/camera connection is the best avenue for unwanted junk, whether it be moisture, dust, or something else, to get into your camera. With a lens that has a rubber gasket at the mount, this problem is eliminated.

In terms of lenses, weather-sealing is one of the newer innovations for the simple reason that film cameras were nowhere near a susceptible to the elements as are today's “superior” digital versions. So, to keep their pros happy, camera makers started building rubber gaskets into their lenses at their most vulnerable points. Below is a complete list of Tamron lenses that are marketed as 'moisture resistant.'

Of all the major lens companies, Tamron has the best website, far and away, for showing just exactly what goes into their weather-resistance as all but a few of the optics have a cutaway diagram (the one above is from the 70-200 f2.8) showing exactly where the rubber gaskets are located. That said, just because a lens has rubber gaskets built in, doesn't mean that it is of professional quality as a few lenses on this list do not even have metal mounts. 

Di Series (Full Frame, APS-C)

15-30 f2.8 VC USD G2
17-35 f2.8-4 OSD
24-70 f2.8 VC USD G2
28-300 f3.5-6.3 VC PZD
35-150 f2.8-4 VC OSD
70-200 f2.8 VC USD G2
70-210 f4 VC USD
100-400 f4.5-6.3 VS USD
150-600 f5-6.3 (both versions)
35 f1.4 USD
35 f1.8 VC USD
45 f1.8 VC USD
85 f1.8 VC USD
90 f2.8 Macro VC USD

Di II (APS-C only)

10-24 f3.5-4.5 VC HLD
16-300 f3.5-6.3 VC PZD Macro
18-200 f3.5-6.3 VC
18-400 f3.5-6.3 VC HLD

Di III (Mirrorless)
17-28 f2.8 RXD
28-75 f2.8 RXD
28-200 f3.5-5.6 RXD
70-180 f2.8 VXD
20 f2.8 OSD 1:2
24 f2.8 OSD 1:2
35 f2.8 OSD 1:2

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MIT Releases Eerie Apollo 11 Disaster 'Deepfake' Video

It has long been known that then-president Richard Nixon already had an alternate speech prepared in the event that the Apollo 11 mission should end in disaster. Now, thanks to technology, the world now has the chance to see Nixon give the speech that, thankfully, he never had to make in real life.

Artificial Intelligence (AI) experts at the Massachusetts Institute of Technology (MIT) spent over a year creating alternate history by using advanced computer technology. By taking historical audio and video and running it through a computer, the MIT team was able to create an eerily convincing video of what history may have looked like if things had gone differently in July, 1969.

Part of the video was released a year ago but only now has the full 7-minute video been made available. For anyone wanting to see the 'speech,' it starts at around the 4:30 minute mark.

While the project owed its impetus to the 50th anniversary of Apollo 11, the MIT team had a more present goal in mind: educate the public about the concept of 'deepfakes,' defined as video forgeries designed to make people look like they're doing and/or saying something that they aren't.

While in years past restricted to special effects studios, video manipulation technology capable of making a convincing fake video of a real person is now well within reach of amateurs. With its video, MIT hopes to educate about what deepfakes are, how to spot them, show how they can be used/misused, and what is being done to combat their misuse.

And as if 2020 wasn't crazy enough already . . .

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After Almost a Decade, Americans Return to Space

For the first time in nearly a decade, the United States has launched astronauts into orbit without having to hitchhike a ride with, ironically of all people, the Russians.

A new era in the history of spaceflight began at 3:22pm yesterday as a SpaceX Falcon 9 rocket lifted off from the Kennedy Space Center carrying NASA astronauts Doug Hurley and Bob Benhken into orbit and to the International Space Station (ISS), becoming the first privately-owned spacecraft to carry astronauts into orbit. The Falcon launched from the historic 39A pad, which saw launches during both the Apollo and Space Shuttle programs.

What would have undoubtedly been a media and public frenzy in normal times was very subdued thanks to the ongoing China-originating COVID 19 Pandemic. Still, though, President Trump and Vice President Pence, who have spearheaded the effort to reassert America’s dominant place in space, were in attendance, with the president declaring “the decades of lost years and little action are officially over.”

To be perfectly honest, America’s space program of the 21^st century to this point could be described as lost not in space, but on the ground.

With mounting calls for the retirement of the Space Shuttle following the 2003 Columbia disaster, then President George W. Bush announced the Constellation Program in 2005, which sought to return Americans to the Moon by 2020 via heavy lift rockets similar to the Saturn V. There were to be two versions of the new Aries rocket: one designed for manned launches and another designed for heavy cargo payloads.

By 2009, a study concluded that Constellation was grossly over budget. As a result, in early 2010, then President Obama announced that Constellation was going to be canceled and replaced with a single rocket: the Space Launch System (SLS), which could be built in multiple configurations while utilizing technology originally developed for Constellation.

Fast forward 9 years and it's more of the same.

The first SLS launch at the program’s 2010 announcement was targeted to be an unmanned capsule sent around the Moon in December, 2017. The first manned flight was targeted for mid 2021. Obviously, December, 2017 is years in the rear view mirror and the SLS has yet to leave the ground. The latest in an ever-slipping schedule has the SLS’s first unmanned launched, now officially titled Artemis 1, taking place in November, 2021.

However, manned American spaceflight has a new champion in President Trump, who has made it very clear that he intends to see to it that Americans will once again be able to not only fly themselves into space, which we now have done, but to the Moon.

Last year, NASA announced that its Project Artemis (the twin sister of Apollo in Greek mythology) seeks to land astronauts on the Moon again by 2024 with the long-term goal being the creation of a permanently manned lunar base that will serve as a stepping stone to Mars. Making the upcoming journey especially interesting is a new player in space that wasn't even imaginable in the 1960s: the private sector, which completely bypasses the shifting winds of party politics in Washington D.C..

While there are now numerous private companies involved in spaceflight, the far and away leader of the proverbial pack is SpaceX.

Looking at SpaceX and what it has achieved since its 2002 founding is like looking at a shopping list. SpaceX was the first private company to: launch a rocket into orbit (2008), orbit and then recover a spacecraft (2010), send a spacecraft to the International Space Station (2012), complete a propulsive landing of a rocket (2015), reuse a rocket (2017), launch a payload into solar orbit (2018), and now launch astronauts into orbit as of yesterday.

The most intriguing possibility, however, is that offered by SpaceX's Falcon Heavy rocket. First launched in February, 2018, according to NASA, the Falcon Heavy is capable of launching astronauts to the Moon, although the SLS is the preferred option. With the SLS falling ever farther behind schedule, there is a very real possibility that the Falcon Heavy could be NASA's ticket to the Moon by 2024 if the SLS is not ready to go in time.

Yes, these are not the 1960s when manned spaceflight was a matter of national priority and pride, but the possibilities offered by the private sector are undoubtedly exciting, too. NASA astronauts riding a privately-owned rocket to the Moon? The idea would have seemed crazy in 1969 but, come 2020, this could be the future of America in space.

The future of manned spaceflight may look different, but the possibilities are truly limitless and with the private sector coming on board, could do a lot to show the world that America’s ingenuity and industry are far and away the best in the world.

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