May is a great month for stargazing with a host of celestial events happening in the morning and evening skies.
On May 17, a slim crescent moon will rise about an hour before the Sun. From much of the United States and Canada, you’ll be able to see Jupiter appearing very close to the Moon. In some southern U.S. states, Jupiter will pass behind the Moon as the pair rises in morning twilight. From western states, Jupiter will be behind the Moon, in occultation, as the duo rise. Jupiter will start to emerge from behind the Moon as the Sun comes up. To observe this event, you’ll need a clear view of the horizon, and a pair of binoculars will be essential as many locations in the U.S. will be in daylight during this occultation.
Following sunset from May 22 through 24, you’ll be able to witness a close grouping of the Moon, Venus, and Mars in the western sky. The Moon will sit between the two planets on the 23rd. Venus has been rising higher in the sky each evening for the past few months, but in May, it’ll reach its highest point in the western sky.
For those stargazing from the Southern Hemisphere, there are some key differences in the night sky compared to the Northern Hemisphere. For instance, there’s no counterpart to the North Star in the Southern Hemisphere, and the seasonal star patterns that a northern observer are familiar with appear flipped upside down when viewed in southern skies.
Two entire galaxies, the large and small Magellanic Clouds, can be easily observed in the southern sky with the unaided eye. These are dwarf galaxies that orbit our own Milky Way galaxy.
The eta Aquariid meteor shower is active throughout April and May, peaking in the pre-dawn hours of May 5. This year could be particularly impressive as an outburst year with 120-160 meteors per hour expected.
“A meteor shower is like a normal rain shower, with 50-60 meteors per hour,” said Bill Cooke, lead of NASA’s Meteoroid Environments Office at the agency’s Marshall Space Flight Center in Huntsville, Alabama. “An outburst is like a thunderstorm, with greater than normal meteor activity expected. A meteor storm is like a tornado, where meteor rates are over one thousand per hour.”
Despite the full moon lighting up the sky and washing out the faint meteors, this year’s eta Aquariid meteor shower is not one to miss. In terms of producing fireballs, NASA camera data places it #6 among meteor showers. These bright fireballs are caused by Earth running into a dense stream of debris from Comet Halley, a lot of which was ejected more than 3,000 years ago. Moving at 148,000 mph, some of these fireballs leave glowing “trains” in their wake that last for several seconds to minutes.
How to View
The eta Aquariid meteor shower is viewable in both the Northern and Southern hemispheres, with higher rates of visibility to observers in the Southern Hemisphere. This is due to the radiant’s location in the constellation of Aquarius. Meteors will be observable after midnight, but the peak times are 3-4 a.m. until dawn.
Regardless of your geographic location, you’ll want to find an area well away from city lights for best viewing. Give yourself about 30 minutes in the dark for your eyes to adapt – this means not looking at your phone. Look AWAY from the moon and take in as much sky as possible.
The next major meteor showers will be the Perseids in August, and the sister show to the eta Aquariids, the Orionids in October.
But there’s plenty more skygazing to do this month. Check out What’s Up in May from NASA Jet Propulsion Laboratory.
This year’s Lyrid meteor shower will peak in the predawn hours of April 23. On average, the shower can produce up to 15 meteors per hour under ideal viewing conditions. The Lyrids occur every year in mid-April, when Earth crosses the trail of debris left by the Comet C/1861 G1 Thatcher. These bits of comet burn up when they hit Earth’s atmosphere and produce this shower of shooting stars. The shower gets its name from the constellation Lyra, the point in the sky where the meteors appear to originate. Unlike the Perseids or Geminids, the Lyrids are not known for bright fireballs. What makes them special is their unpredictability.
The first record of the Lyrid meteor shower dates back 2,700 years, making it one of the oldest in history. Researchers looking though old records have found descriptions of major Lyrid outbursts. For example, a notation made by the French bishop Gregory of Tours in April of 582 A.D. states, “At Soissons, we see the sky on fire.” There was also a Lyrid outburst visible over the United States in 1803. An article in the Virginia Gazette and General Advertiser describes the shower: “From one until three, those starry meteors seemed to fall from every point in the heavens, in such numbers as to resemble a shower of sky rockets.” The last Lyrid outburst was in 1982, when 75 meteors per hour were recorded by observers in Florida.
The common theme here is that Lyrid outbursts are surprises. Unlike some other showers, meteor researchers aren’t able to predict Lyrid outbursts as well. That’s why it is important to make observations each year so that models of its activity can be improved.
How can you best observe the Lyrids? After 10:30 p.m. local time on the night of April 22, find a dark place away from city lights with open sky free of clouds and look straight up. It will take about 30 minutes for your eyes to get acclimated to the dark. Don’t look at your cell phone – the bright light from its screen will interrupt your night vision. You will begin to see Lyrids, and as the night progresses the meteors will appear more often, reaching 10 to 15 per hour in the pre-dawn hours of the 23rd. You can see Lyrids on the night before and after the peak, but the rates will be lower, maybe five per hour or so.
For the second time in 2022, stargazers will have the opportunity to view a total lunar eclipse on Nov. 8. At least a portion of the phenomenon will be visible throughout eastern Asia, Australia, the Pacific, and North America. The previous total lunar eclipse happened in May.
According to Alphonse Sterling, astrophysicist from NASA’s Marshall Space Flight Center in Huntsville, Alabama, total lunar eclipses occur approximately once every 1.5 years on average. While the Moon has been providing generous eclipse viewing opportunities this year, viewers should take advantage of November’s eclipse because the next total lunar eclipse will not occur until 2025.
A total lunar eclipse occurs when Earth casts a complete shadow – called an umbra – over the Moon. Earth’s shadow is categorized into two parts: the umbra, the innermost part of the shadow where direct light from the Sun is completely blocked, and the penumbra, the outermost part of the shadow where the light is partially blocked.
During a total lunar eclipse, the Moon and the Sun are on opposite sides of Earth. Many people wonder why lunar eclipses don’t happen every month given the Moon completes an orbit around Earth every 27 days. The reason is because the Moon’s orbit around Earth is tilted relative to Earth’s orbit around the Sun, so the Moon often passes above or below Earth’s shadow. Lunar eclipses are only possible when the orbits align so that the Moon is directly behind Earth relative to the Sun.
For North America the action will start in the early hours of the morning on Nov. 8. The partial eclipse will begin at 3:09 a.m. CST, with totality beginning at 4:16 a.m. and ending at 5:42 a.m. Then, the partial phase will resume, lasting until 6:49 a.m. Those in the eastern part of the United States will miss most or all of the last partial phase because the Moon will set during totality or shortly after totality ends.
Another feature of a total lunar eclipse is the Moon’s red hue during totality. The red color occurs because of the refraction, filtering, and scattering of light by Earth’s atmosphere. The scattering is a phenomenon called Rayleigh scattering – named after the 19th-century British Physicist Lord Rayleigh.
Rayleigh scattering is also the reason for red sunrises and sunsets. Light from the Sun collides into the gases of Earth’s atmosphere and because of its shorter wavelength, blue light is filtered out, but red light is not easily scattered because of its longer wavelength. Some of that red light is refracted, or bent, as it passes through Earth’s atmosphere and ends up shining on the Moon with a ghostly red light. The degree of redness of a fully eclipsed Moon can be influenced by atmospheric conditions resulting from volcanic eruptions, fires, and dust storms.
But what does Earth look like from the Moon’s perspective during a lunar eclipse? According to Mitzi Adams, astrophysicist at Marshall, astronauts on the Moon during a total lunar eclipse would see a red ring around a silhouetted Earth. As NASA works to establish a permanent human presence on the Moon through the Artemis program, it’s fascinating to consider how Earthlings will experience astronomical events away from their home planet.
No special eye protection is needed for viewing a lunar eclipse, unlike solar eclipses (which occur during the daytime). While the lunar eclipse can be observed with the unaided eye, a pair of binoculars or a telescope can enhance the view.
Sterling says a fun activity for those who stargaze with family or friends is to discuss who notices the reddish hue of totality first and how it progresses throughout the eclipse.
Complemented by cooler temperatures and falling leaves, the September equinox marks the beginning of the fall season for the Northern Hemisphere. This year’s autumnal equinox (for the Northern Hemisphere) or spring equinox (for the Southern Hemisphere) occurs on Sept. 22 at 8:04 p.m. CDT.
During an equinox the Sun shines directly over the equator resulting in nearly equal amounts of day and night throughout the world – except for the North and South Pole where the Sun approximately straddles the horizon for the entire day, according to Alphonse Sterling, an astrophysicist at NASA’s Marshall Space Flight Center in Huntsville, Alabama. Following the autumnal equinox, the Sun gradually continues to rise later and set earlier in the Northern Hemisphere – making the days shorter and the nightfall longer. The opposite is true in the Southern Hemisphere where the days begin to last longer.
Seasons are caused by Earth’s tilted axis which always points in the same direction. As Earth orbits around the Sun, the angle of sunlight that the Northern and Southern Hemispheres receive is different. “On the June solstice (summer) in the Northern Hemisphere, sunlight is more direct, so it warms the ground more efficiently,” said Mitzi Adams an Assistant Manager in the Heliophysics and Planetary Science Branch at Marshall. “In the Southern Hemisphere, sunlight is less direct (winter), which means that the ground is not heated as easily.”
Astronomical seasons are defined by the Earth’s journey around the Sun, while meteorological seasons are guided by annual temperature cycles. Meteorologists group the seasons into time periods that line up with the weather and monthly calendar: December through February is winter, March through May is spring, June through August is summer, and September through November is fall. Astronomical seasons are marked by the equinoxes and solstices that each happen twice a year. Solstices are when the Sun appears to reach the lowest or highest point in the sky all year; they mark the beginning of summer or winter. Solstices are commonly referred to as the longest (summer solstice) or shortest (winter solstice) day of the year.
The September equinox is a time that welcomes Earthlings to a new season. To those in the Northern Hemisphere, enjoy the beginning of milder weather and say hello to early sunsets and late sunrises.
Saturn will have one of its best viewing opportunities of the year in the period surrounding Sunday, Aug. 14. Or it would, if the nearly Full Moon doesn’t spoil our fun.
On that date, Saturn will reach opposition – the point where it lies directly opposite the Sun in our night sky – around midnight local time for most stargazers, with the constellation Capricornus behind it.
Saturn will be visible for much of the night, rising above the southeastern horizon and lingering high in the southern sky. This will occur during Saturn’s perigee – its closest approach to Earth – making it even larger and brighter than usual.
But as previously noted the last blog, the Moon will become full Aug. 11-12, and its bright wash of light will challenge spotters to clearly make out much around it in the night sky. Hopefully, Saturn’s position – west of the rising Moon – won’t cause it to be directly impacted.
The best thing about opposition this year is that Saturn will be visible all night long, said Caleb Fassett, a planetary scientist at NASA’s Marshall Space Flight Center in Huntsville, Alabama. “That gives stargazers a good, long chance to find and observe it,” he said.
And despite the light-clutter from the Moon, all may not be lost. The rings of Saturn will face Earth at a 13-degree angle to our line of sight. And though Saturn is much farther from the Sun than our planet – an average 886 million miles out, compared to 94.4 million for Earth – a unique phenomenon may lend it even greater brightness during opposition.
The Seeliger effect, named for German astronomer Hugo von Seeliger, who died in 1924, identifies a dramatic brightening of a distant body or particle field when illuminated from directly behind the observer. With Earth passing between Saturn and the Sun, the sixth planet’s icy rings are likely to brighten perceptibly in the hours around opposition.
Even so, it will still require a telescope to spot Saturn – which takes 29.4 Earth years to complete a single solar orbit – as anything more than a bright point of light.
Fassett recommends a 4-inch to 8-inch telescope to fully resolve the rings and provide a good look at the planet itself during opposition. With a decent telescope, it may even be possible to catch a glimpse of Titan and other Saturnian moons.
“It’s always pretty cool to see the distant planets, and Saturn is wild,” Fassett said. “Its rings and other unique characteristics make it a great subject of study for amateur astronomers and young space enthusiasts, and its moons are of great scientific interest.”
Among them is Titan, largest of Saturn’s moons, and the destination for NASA’s planned Dragonfly mission. Set to launch in 2027, Dragonfly will deliver an 8-bladed rotorcraft to the icy surface of Titan in the mid-2030s. There, it will examine the atmosphere and take samples of the surface, advancing our search for the building blocks of life and characterization of Titan’s habitability.
Astronomers are excited about the possibility of a new meteor shower May 30-31. And that excitement has sparked a lot of information about the tau Herculids. Some has been accurate, and some has not.
We get excited about meteor showers, too! But sometimes events like this don’t live up to expectations – it happened with the 2019 Alpha Monocerotid shower, for example. And some astronomers predict a dazzling display of tau Herculids could be “hit or miss.”
So, we’re encouraging eager skywatchers to channel their inner scientists, and look beyond the headlines. Here are the facts:
On the night of May 30 into the early morning of May 31, Earth will pass through the debris trails of a broken comet called 73P/Schwassmann-Wachmann, or SW3.
The comet, which broke into large fragments back in 1995, won’t reach this point in its orbit until August.
If the fragments from were ejected with speeds greater than twice the normal speeds—fast enough to reach Earth—we might get a meteor shower.
Spitzer observations published in 2009 indicate that at least some fragments are moving fast enough. This is one reason why astronomers are excited.
If a meteor shower does occur, the tau Herculids move slowly by meteor standards – they will be faint.
Observers in North America under clear, dark skies have the best chance of seeing a tau Herculid shower. The peak time to watch is around 1am on the East Coast or 10pm on the West Coast.
We can’t be certain what we’ll see. We can only hope it’s spectacular.
Most stargazers will have a prime viewing opportunity to see the planets Mars and Jupiter draw incredibly close in the predawn sky on the nights of May 27-30.
The two planets will appear 20 degrees or so above the horizon in the eastern-southeastern sky, against the constellation Pisces, approximately 45 minutes before local sunrise. This Mars-Jupiter conjunction will be visible, barring local weather issues, in the predawn hours each morning from May 27 to May 30. The conjunction will peak at 3:57 a.m. CDT on May 29.
“Planetary conjunctions traditionally have been more the stuff of astrology than serious astronomy, but they never fail to impress during observations, particular when the gas giants are involved,” said Mitzi Adams, an astronomer and researcher at NASA’s Marshall Space Flight Center in Huntsville, Alabama.
During such a conjunction, two planets appear close together in Earth’s night sky. In the case of Earth’s solar system, conjunctions happen frequently because our sister planets travel around the Sun in a fairly similar ecliptic plane, often appearing to meet in our night sky despite being millions of miles away from one another.
At their closest point, Mars and Jupiter will be separated by no more than 0.6 degrees. Astronomers routinely use degrees to measure the angular distance between objects in the night sky. To observers on the ground, the distance between the two planets will be no more than the width of a raised finger, with Mars appearing just to the lower right of the massive gas giant.
It might be necessary to use binoculars or a telescope to spot Mars clearly, said Alphonse Sterling, a NASA astronomer who works with Adams at Marshall. But he noted that observers should have no trouble identifying Jupiter, even with unaided eyes.
“We anticipate Jupiter will shine at a magnitude of -2.2,” Sterling said. “Mars, in comparison, will have a magnitude of just 0.7.”
The brightness of celestial bodies is measured according to their magnitude value, a number which decreases as brightness increases. A negative value indicates the planet or moon is easy to see in the night sky, even with ambient light from one’s surroundings.
Mars and Jupiter are millions of miles away from us, of course – more than 136 million miles will separate Earth and Mars at the time of the conjunction, with Jupiter nearly four times further away. Even so, Jupiter will be the far brighter of the two. With its planetary diameter of around 4,200 miles, Mars is dwarfed by the massive Jovian giant, which has a diameter of about 89,000 miles. Being so much smaller, Mars reflects far less sunlight.
Mars also orbits the Sun more quickly, spinning eastward in our night sky fast enough to leave its lumbering gas-giant counterpart behind. Mars will catch up to Jupiter again and pass it during another conjunction in August 2024.
Adams and Sterling look forward to spotting the planetary conjunction.
“It’s thrilling to look up and recognize that these two worlds represent the breadth of NASA’s planned and potential goals for science and exploration,” Adams said. “As NASA prepares to send the first human explorers to the planet Mars, the possibilities could be virtually limitless for groundbreaking science discoveries among Jupiter’s fascinating moons.”
“This conjunction brings together two vastly different worlds, which both hold incredible promise to help us better understand our solar system, humanity’s place in the cosmos, and where we may be headed as a species,” Sterling added.
“Get outside before sunrise on May 29 and see them for yourself – and imagine all we’ve yet to learn from them,” he added.
Enjoy this celestial event as you watch the skies!
On the night of May 15, and into the early hours of May 16, skywatchers will be treated to a phenomenon which takes place every 1.5 years or so: a total lunar eclipse.
Total lunar eclipses occur when the Moon and Sun are on opposite sides of Earth and the planet casts a complete shadow, or umbra, over its sole natural satellite. There may be multiple partial lunar eclipses each year, but total eclipses are a bit rarer. Best of all, unlike the precautions one takes to observe a total solar eclipse, it’s completely safe to watch a lunar eclipse unfold with the unaided eye. Even so, binoculars or a powerful telescope definitely can enrich the experience.
The partial eclipse phase will begin over North America at 9:28 p.m. Central Daylight Time on May 15. Totality will begin at 10:29 p.m. CDT, concluding about midnight. After totality, the partial phase will end at 12:56 a.m. CDT on May 16.
This full Moon was known by early Native American tribes as the Flower Moon because this was the time of year when spring flowers appeared in abundance.
Mitzi Adams and Alphonse Sterling, both astronomers at NASA’s Marshall Space Flight Center in Huntsville, Alabama, are particularly excited to observe the lunar eclipse. One of the most recent such events they documented – in January 2018 – was very low on the horizon, with trees and buildings partially obscuring the eclipse during totality.
Then, of course, the global COVID-19 pandemic put a damper on eclipse watch parties in 2020-2021.
“It’s exciting to get back to holding astronomical society events in person, where it’s safer to share a telescope eyepiece,” Adams said.
Unlike a total solar eclipse – in which ideal viewing is limited to a roughly 100-mile-wide “path of totality” as the shadow of Earth’s Moon sweeps across the land relative to the position of the Sun – a lunar eclipse has no such limits.
“The whole half of Earth in darkness during those hours will be able to see it,” Sterling said. “You don’t have to work too hard to find a good vantage point. Just go outside!”
What can viewers expect to see? As Earth’s shadow deepens on the face of the Moon, it will darken to a ruddy, red color, with its intensity depending on atmospheric interference.
It’s no surprise observers coined the ominous-sounding phrase “blood moon,” but the effect is completely natural. During the eclipse, most visible-spectrum light from the Sun is filtered out. Only the red and orange wavelengths reach the surface.
The blocking of the Moon’s reflected light has another benefit, Adams said.
“No moon means more visible stars,” she said. “During totality, if the skies are clear, we may even be able to see the Milky Way itself, showing up as a hazy white river of stars stretching away in a curving arc.”
Sterling notes that the long duration of the total eclipse offers amateur shutterbugs plenty of time to experiment with photographing the event. He recommends trying varying exposure times with conventional cameras for maximum effect.
He and Adams both emphasize the value of putting the camera aside, as well.
“Just watch it happen,” Adams said. “Looking at the Moon, it’s hard not to think about the people who actually walked there, and about those who soon will do so again – when NASA’s Artemis program launches the next human explorers to the Moon in coming years.”
Sterling said the most valuable aspect of the event is the chance to spark wonder in young minds. “We don’t get a lot of groundbreaking astronomical information from lunar eclipses, but they’re a great way to inspire discussion and engage the astronomers and explorers of tomorrow,” he said.
A fiery meteor streaked across the morning skies in southern Mississippi yesterday on April 27, 2022.
More than 30 eyewitnesses in the states of Arkansas, Louisiana and Mississippi reported seeing a bright fireball at 8:03 a.m. CDT. The sighting was soon followed by numerous reports of loud booms heard in Claiborne County, Mississippi, and surrounding counties.
Approximately 22,000 miles out in space, NOAA’s Geostationary Lightning Mappers (GLM) onboard the Geostationary Operational Environmental Satellites (GOES) 16 and 17 detected several bright flashes associated with the fragmentation’s of this bolide, or exceptionally bright meteor, which was first spotted 54 miles above the Mississippi River near the Mississippi town of Alcorn.
The object – thought to be a piece of an asteroid about a foot in diameter with a weight of 90 pounds – moved southwest at a speed of 55,000 miles per hour, breaking into pieces as it descended deeper into Earth’s atmosphere. It disintegrated about 34 miles above the swampy area north of Minorca in Louisiana.
The fragmentation of this fireball generated an energy equivalent of 3 tons of TNT (trinitrotoluene), which created shock waves that propagated to the ground, producing the booms and vibrations felt by people in the area.
At its peak, the fireball was over 10 times brighter than the Full Moon.
“What struck me as unusual was how few eyewitness reports we had given the skies were so clear,” said Cooke. “More people heard it than saw it.”