Witnessing an astronomical event is a once-in-a-lifetime experience. Seeing a total solar eclipse, witnessing triple conjunctions of the planets, and gawking in awe at a comet passing across the sky are completely special, unique experiences. They may never happen again. Even if you’re looking for smaller events, like lunar and solar eclipses or the equinox, it’s important to plan to catch these magical events in the sky. It could be something you’re telling your grandchildren about one day.
Time and Date
Transit of Venus
The next pair of Venus transits won’t occur until 2117 and 2125. A transit of Venus means Venus passes directly between the sun and another superior planet. Because of this, it becomes completely visible against the solar disk. It looks like a small black dot moving across the sun. The previous transit of Venus took place on June 6th, 2012. It was the last Venus transit of the century.
According to Exploratorium, “Venus transits occur eight years apart—and then don’t happen again for more than a century. The last transit before 2004 took place in 1882.” The next one won’t occur until December 11th, 2117. It looks like our grandchildren will be the lucky ones to watch this next event (Exploratorium).
Phys
Halley’s Comet
Halley’s Comet is a short-period comet that returns approximately every 76 years, so if you missed it in 1986, you’ll have to wait until 2061. That’s good news for most of us, and if you were born after 1986, you’ll likely be able to catch the next one. It’s important because it’s the first time astronomers understood that comets could be repeat visitors to our dark, night skies.
According to Science NASA, “Halley’s dimensions are about 9.3 by 5 miles (15 kilometers by 8 kilometers). It is one of the darkest, or least reflective, objects in the solar system. It has an albedo of 0.03, which means that it reflects only 3% of the light that falls on it.” It moves in the opposite direction to Earth’s orbit. In the year 837, it was the closest it’s ever been to Earth (Science).
NHM
A Total Solar Eclipse
A solar eclipse occurs when the moon passes between the Earth and the Sun, and they line up exactly. The diameter of the sun is 400 times that of the moon, but it’s also 400 times farther away. While it’s more likely you’ll be able to see a couple of total solar eclipses in your lifetime, the path of totality for each solar eclipse is different, so some locations may not experience one for centuries.
If you’re willing to travel for a solar eclipse, then you’ll have more chances of seeing one. There are at least two solar eclipses per year somewhere on Earth. From any one place, total solar eclipses are visible every 400 years. If you don’t want to leave your hometown, then hopefully you’re within these 400 years (NHM).
Phys
Annular Solar Eclipse at the North Pole
If you happen to be at the North Pole, then hopefully you were there back in 2003 to watch the annular Solar Eclipse. It won’t happen again until 2050. According to AGU Newsroom, “On 10 June 2021, the moon’s shadow darkened much of the Earth’s northern polar region, providing scientists with an unprecedented opportunity to explore the impacts natural events have in Earth’s geospace, thousands of kilometers above Earth.”
It affected the auroras in both the Northern and Southern hemispheres. According to Researcher Tong Dang, “Excitingly, we found that the aurora and upper atmosphere were disturbed in the Southern Hemisphere where the eclipse did not cover. This is because the upper atmosphere in the two hemispheres is connected through the magnetic field lines and the magnetosphere.” Either way, it won’t happen again for another couple of decades, and it’s unlikely that most of us will witness it in the North Pole (News).
The Christian Science Monitor
Transit of Mercury in Front of the Sun
While this isn’t as rare as some of the other events on this list, it’s still one that doesn’t occur every month. The next transits of Mercury occur in 2032 and 2039. This transit occurs when Mercury crosses directly between the Sun and the Earth, blocking out a small part of the Sun’s rays. Mercury appears as a tiny black dot moving across the Sun.
Transits are rare in general, and cloud coverage can prevent you from seeing one. You need to use a telescope or a long lens to view this transit, with a pair of solar filters. Astronomer Tom Kerss said, “Although Mercury overtakes us several times per year on its relatively quick journey around the Sun, we don’t see transits every time, because Mercury’s orbit is quite highly inclined relative to that of the Earth. Fortunately, transits of Mercury are considerably more common than transits of Venus.” You’ll need to mark the date on your calendar to see the next one (RMG).
Springfields Museum
Great Conjunction between Jupiter and Saturn
These occur roughly every 20 years, with the next one in 2080. According to Sky and Telescope, “During this period, Saturn completes two-thirds of its 30-year orbit, while Jupiter completes one lap of its 12-year orbit plus two-thirds of its next one. The odd two-thirds of an orbit mean that successive conjunctions are separated in the sky by about 240 degrees.”
Back in 1606, Johannes Kepler recognized these conjunctions and created a near-perfect triangle on the zodiac circle. The last conjunction was in 2020, and after the next one in 2080, the next ones will occur in 2417 and 2477 (Sky and Telescope).
Mars Nasa
Opposition of Mars at its Closest
Mars comes closest to Earth roughly every 15 to 17 years, with the last one in 2020. According to NASA, the “opposition occurs within a few weeks of Mars’ perihelion (the point in its orbit when it is closest to the sun). An opposition can occur anywhere along Mars’ orbit. When it happens while the red planet is closest to the sun (called “perihelic opposition”), Mars is particularly close to Earth.”
If you missed the last one, make sure you try and catch the next one. Back in 2003, the opposition was the closest approach in almost 60,000 years, and is something that will never happen in our lifetime again (Mars).
NY Post
Triple Conjunction of Mars, Jupiter, and Saturn
When two or more planets align in the night sky, it’s called a triple conjunction. What matters most is the line of sight, because Saturn, Jupiter, and Mercury take a different amount of time to orbit the sun. According to Travel and Leisure, “Distant Saturn takes 29 years, Jupiter 12 years, and tiny Mercury just 88 days. Since Mercury is the first planet from the sun and we’re on the third planet, it’s an inner planet to us. So, just like Venus, Mercury always appears to be relatively close to the sun.”
The last triple conjunction occurred in 2021. To spot it, you needed to be low on the west-southwest horizon, and in a place with no cloud cover. The best time to have seen it was right after sunset. The next one won’t occur until 2148-2149 (Travel and Leisure).
Mars
Transit of Phobos (Moon of Mars) Across the Sun
Mars has two moons named Phobos and Deimos that rarely pass in front of the sun, similar to the other planets in transit. According to NASA, “As part of a multi-mission campaign, NASA’s Curiosity rover is observing these transits, the first of which involved the moon Phobos grazing the sun’s disk. The event was observed on Martian day, or Sol, 37 (September 13, 2012) using Curiosity’s Mast Camera, or Mastcam, equipped with special filters for directly observing the sun.”
They used a series of high-resolution video frames at three frames per second, for roughly two minutes. Phobos blocked out five percent of the sun. These transits are exceedingly rare due to Phobos’ small size and irregular orbit (NASA).
Universe Today
Opposition of Uranus or Neptune
These occur approximately every year, but they’re not always observable due to their distance and orbital positions which makes it incredibly rare to witness one. When planets are in opposition, they’re at their largest and brightest in the night sky.
Astronomy photographer Steve Marsh said, “If you want to get the best photo of a planet you want to try and aim for when it’s riding high in the sky and ‘at opposition. You want the air to be nice and still. If you can get all those three things combined then you are going to have a great picture at the end of it.” Make sure you capture a photo of this rare event (RMG).
Sky At Night Magazine
Transit of Earth from Mars
This will never be visible in our lifetime unless humans establish a permanent presence on Mars, which will likely not happen anytime soon. As spectacular as it would be to watch our planet from Mars, it’s more likely we’re stuck here for the time being.
According to Sky and Night magazine, “A transit of Earth can be seen from Mars in intervals of between 25 and 100 years. These transits usually occur in pairs 79 years apart, similar to the transits of Venus seen from Earth (where pairs of transits are 8 years apart, but the pairs themselves are over 100 years apart).” At the very least, this is something our grandchildren might be able to see (Sky at Night Magazine).
Quora
Passage of Voyager 1 beyond the Oort Cloud
You’d think that by flying at a speed of one million miles per day, Voyager 1 would leave the solar system tomorrow. And even though it may leave the solar system entirely, it will likely be beyond our lifetimes. NASA says, “But it will take about 300 years for Voyager 1 to reach the inner edge of the Oort Cloud and possibly about 30,000 years to fly beyond it.”
The Oort cloud, a hypothesized reservoir of comets and icy debris extending far beyond the furthest reaches of our solar system, remains an elusive frontier in astronomical study. Despite its enigmatic nature, Voyager 1’s trajectory suggests that it will continue to navigate within the boundaries of our solar system, providing invaluable insights into the outer realms of space exploration.(Voyager).
Science NASA
Close Conjunction of the Galilean Moons of Jupiter
The last close conjunction was in 2009; these events are infrequent and difficult to predict. NASA’s Hubble Space Telescope captured the event in a string of snapshots. Jupiter’s moons, Europa, Callisto, and Io, raced across the sky and crossed in front of the planet.
According to NASA, “The ancient cratered surface of Callisto is brownish; the smooth icy surface of Europa is yellow-white; and the volcanic, sulfur-dioxide surface of Io is orange. ” There was a fourth moon, but it was outside Hubble’s field of view (Science NASA).
Astronomy on Tap
Occultation of a Bright Star by an Asteroid
These are rare and depend on the observer’s location. According to Unistellar, “Asteroids are small, rocky bodies that orbit the Sun. Occasionally, one of these asteroids will fly in front of a distant star, blocking its light. This event called an occultation, casts a shadow on the Earth that can be recorded by Citizen Astronomers in the shadow’s path.”
If you happen to be in the exact, observable location of this phenomenon, then you’re lucky. Scientists often study these occultations to get a better idea of asteroids and stars (Unistellar).
Astronomy
Passage of Gliese, A Nearby Star within 1 Light-Year
Every 50,000 years, a nomadic star passes near our solar system. Most of the time, they pass by without any event. But sometimes, they come so close that they’re visible in Earth’s night sky. Close stellar encounters are very rare and typically occur on timescales of millions of years. The last one would have been while the Neanderthals were wandering on the planet.
According to Astronomy, “The most famous of these stellar interlopers is called Scholz’s Star. This small binary star system was discovered in 2013. Its orbital path indicated that, about 70,000 years ago, it passed through the Oort Cloud, the extended sphere of icy bodies that surrounds the fringes of our solar system.” In about 1.4 million years, Gliese 710 will pass very close to Earth as a brilliant orange globe, outshining every other star in the night sky (Astronomy).
News Northwestern
Detection of a Nearby Supernova
While supernovae occur regularly in the universe, detecting one nearby is rare. It’s also very unlikely that there’s a nearby supernova, since if one happened to explode within 25 light-years of Earth, our planet would completely perish and we’d lose our atmosphere.
According to Adam Miller, who is currently working on AI detection of Supernovas, “For the first time, a series of robots and AI algorithms have observed, then identified, then communicated with another telescope to finally confirm the discovery of a supernova. This represents an important step forward as further refinement of models will allow the robots to isolate specific subtypes of stellar explosions.” Without humans leading the research, it gives them more time to analyze data. This is the first time this has ever happened in astrological history, so we’re living during a pretty special time (News Northwestern).
NY Post
Discovery of a New Type of Celestial Object
These discoveries are unpredictable and depend on advances in technology and observational techniques. However, recently, astronomers discovered a new celestial object in the sky and predicted it might be a black hole. According to the New York Post, “Astronomers have discovered a mysterious unknown object in our galaxy that could be a breakthrough in the study of black holes.”
Apparently, “The “extremely dense remnant of a collapsed star” lies about 235,000 trillion miles away from Earth in a globular cluster of stars in the Milky Way.” Furthermore, according to Astronomer Ben Stappers, “Either possibility for the nature of the companion is exciting. A pulsar-black hole system will be an important target for testing theories of gravity and a heavy neutron star will provide new insights in nuclear physics at very high densities.” Let’s hope they discover what this celestial object is during our lifetime since discoveries to this degree are quite rare (NY Post).
Astronomy
Close Flyby of a Large Asteroid or Comet
While small objects pass near Earth regularly, large ones come closer less frequently. Every thousands, or millions of years, we’ll get lucky enough to see an asteroid or comet pass close enough to Earth that it makes itself known. This happens once every 7,500 years.
Even though it would seem like an incredible experience to watch a nearby comet, if it gets too close, the results may be disastrous. Apparently, “Fortunately, according to NASA, asteroids larger than about 330 feet (100 m) in diameter are only expected to strike Earth roughly once every 10,000 years. Meanwhile, nearly apocalyptic asteroids, those larger than about 0.6 miles (1 km) wide, are expected to strike our planet once every several hundred thousand years or so.” Let’s hope that’s long after our time here on Earth (Astronomy).
David Darling
Detection of a Hypervelocity Star
These rare stars are ejected from the galaxy at high speeds and are challenging to detect, though spotting one is certainly a once-in-a-lifetime experience. According to David Darling, “In 2005, the first hypervelocity star was discovered by astronomers using the Multiple Mirror Telescope in Arizona. Known as SDSS J090745. 0+024507, it is 71 kiloparsecs from the Sun and moving through the outskirts of the galaxy – the so-called galactic halo – at about 850 kilometers per second (528 miles per second).”
This incredible discovery is not a common one, and it’s spectacular that it even happened now. Astronomers predict these stars are thrown out of the galaxy center once every 100,000 years. Approximately 1,000 hypervelocity stars are heading out of the Galaxy. These stars help astronomers understand black holes (David Darling).
Fox Weather
Discovery of an Earth-like Exoplanet with Signs of Life
Do you believe aliens exist? Surely there’s another living species somewhere out in space! While this is a focus of exoplanet research, it’s uncertain when such a discovery will occur. It very well might not be anytime during our lifetime, or our grandchildren’s lifetimes.
While we might not meet aliens anytime soon, exoplanet K2-18 b shows signs of life. According to Euronews, “It found the presence of carbon-bearing molecules – which include methane and carbon dioxide – which is fuelling speculation that K2-18 b might have a hydrogen-rich atmosphere and a water ocean-covered surface. These features could potentially be signs of a planet that could bear life.” Perhaps this planet has more life than we expect (Euro News).
The Conversation
Detection of a Primordial Black Hole
Primordial black holes, if they exist, would be challenging to detect and would provide insights into the early universe. Scientists have never truly figured out what happens after entering a hole since nothing has ever come out. The existence of a primordial black hole is completely hypothetical.
They were proposed by some scientists to explain the unexpected very large early galaxies originally discovered by the James Webb Space Telescope (JWST). At the very least, scientists hope these will help them discover more about dark matter. According to The Conversation, “Primordial black holes might be located in galactic regions where the concentration of dark matter is remarkably high. Thus, they could roam the Universe (moving at different speeds and directions) and eventually interact with other astronomical objects (such as black holes or neutron stars).” There’s no saying if this discovery will ever be made during our human existence (The Conversation).
Forbes
The 2029 Lunar Eclipse
You better get ready for 2029. With an umbral eclipse magnitude of 1.84362, it will be the largest total lunar eclipse of the 21st century, which means it’s the biggest one during our lifetime. It will be a Blood Moon eclipse. This large moon will pass through the umbral shadow of the Earth.
The last one occurred in November 2022, when there was a chance to see shooting stars next to the moon. According to Forbes, “The next totality to beat next week’s—and surpass it, in fact—will be a 102-minute event on June 26, 2029. That one will be visible from North America, South America and the Pacific, the Atlantic, Europe and Africa.” This is one to mark in your calendar (Forbes).
Science
Discovery of a New Moon around a Giant Planet in our Solar System
Moons are still being discovered, but new ones around the gas giants are increasingly rare. Scientists have discovered most of what there is to discover, though it doesn’t mean they’ve found everything. Maybe one day they’ll be able to study other galaxies in depth, but for now, we’re left with the discoveries already made.
According to the Hubble Site, recently, “Astronomers have announced the discovery of at least two, and possibly as many as four, new moons orbiting the giant planet Saturn. This discovery was based upon Hubble telescope images that were taken when Saturn’s rings were tilted edge-on to Earth.” They have similar orbits to that of Prometheus and Atlas, a pair of moons originally discovered in 1980 by Voyager 1 (Hubble Site).
Sci-Tech Daily
Detection of a Gamma-Ray Burst from a Nearby Source
To put it simply, GRBs are short-lived bursts of gamma-ray light. These energetic events are unpredictable and occur randomly in distant galaxies. They typically last a few milliseconds to several minutes and are hundreds of times brighter than your typical Supernova.
According to GFSC, “Evidence from recent satellites like Swift and Fermi indicate that the energy behind a gamma-ray burst comes from the collapse of matter into a black hole.” Unfortunately, seeing matter disappear into a black hole isn’t something that happens every day (Imagine).
Many Worlds
Close Approach of a Rogue Planet to our Solar System
While unlikely, a close encounter with a rogue planet would be a rare and significant event. It’s way more likely we’d see a comet or asteroid come close to our planet than a random, rogue planet. This is because the closest planet is light-years away. As Many Worlds writes, ” The nearest rogue planet to our Earth is WISE-0855-0714. It was discovered in 2014 and is approximately 7.2 light-years away from us.” Simply put, this means that the planet isn’t coming near us anytime soon, though it is spectacular that one planet is not too far away from us now.
NASA’s Nancy Grace Roman Telescope is observing rogue planets. According to Naoki Koshimoto, author of a study regarding rogue planets, “Roman will be sensitive to even lower-mass rogue planets since it will observe from space. The combination of Roman’s wide view and sharp vision will allow us to study the objects it finds in more detail than we can do using only ground-based telescopes, which is a thrilling prospect.” It would be a miracle to have these findings during our lifetime (Many Worlds).
Quora
A Ninety-Degree Arc
In 2492, we might see a ninety-degree arch or all eight planets in our Solar System. Belgian astronomer Jean Meeus predicts that the orbits of all eight planets and Pluto will be within the same 90° arc of the Solar System. Even though this has not happened during our lifetime, it’s something that could happen in the future.
It has been thousands of years since this occurred. The last time this is believed to have occurred was on February 1, 949. Unfortunately, we won’t be alive for this 25th-century alignment, so we can only predict this will happen. At the very least, imagining this alignment is spectacular (Wiki).
AFR
A Total Solar Eclipse in Australia
In July 2028, which is only four years from now, a total solar eclipse will be visible across Australia. This includes the city of Sydney. New Zealand will also see the eclipse. This event is spectacular because Sydney will not see another total solar eclipse until June 3, 2858. If you’re going to be in Australia in four years, you mustn’t miss this event, since it will be the only one in your lifetime.
Australia has seen several eclipses within 15 years, making it a very lucky country. According to Forbes, “Sure, it’s a vast place—the planet’s sixth largest country—but to have five of nature’s greatest events on show in the same country is a rare thing indeed.” That makes this solar eclipse an even rarer one than normal (Forbes).
In the Sky
Leap Day Full Moon
Once a century, we see a full moon on the leap day in February, on the 29th. In 2048, there will be a rare full moon on a leap day; this event happens roughly once every century. The next full moon on a leap day will not occur until February 29, 2124.
According to NBCDFW, “In 2048, a very rare February full Moon occurrence will happen – when the full Moon occurs on Leap Day, February 29th. The timing of this one day every four years coincides so infrequently with the lunar phase cycle that there will only be four Leap Day full Moons this millennium, with 2048 being the first. The other three Leap Day February full Moons will occur in 2132, 2216, and 2376.” This is quite a once-in-a-lifetime experience, so it’s important to make this day a special one (NBCDFW).
Sky & Telescope
Two Solar Eclipses in One Year
Get ready for the year 2057, because this year we will see an incredibly rare occurrence. This is when two solar eclipses in a single calendar year will occur, on January 5th and December 26th. The last time this occurred was well before our time, in 1889. The next time it will occur is 2252.
The year 2057 will also see two lunar eclipses, so it’s best to get your calendar out and start planning these astronomical events. According to Time, this solar eclipse will occur on “January 5, 2057 in the Southern Atlantic, Southern Indian,” and on “December 26, 2057 in Antarctica.” Though it’s unlikely we’ll see the solar eclipse from Antarctica, watching it early on in the year from Southern India is certainly doable. Further down the line, on April 30, 2060, there will be a total Solar Eclipse in the “Ivory Coast, Ghana, Togo, Benin, Nigeria, Niger, Chad, Libya, Egypt, Turkey, Kazakhstan, Russia.” These predictions are based on the sun’s seasonal arc-like path (Time).