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.
Most particles are no bigger than dust and sand. Hitting the upper atmosphere at speeds up to 45 miles per second, they flare and burn up. On any given night, the average person can see from 4 to 8 meteors per hour. Meteor showers, however, are caused by streams of comet and asteroid debris, which create many more flashes and streaks of light as Earth passes through the debris field.
“It’s a perfect opportunity for space enthusiasts to get out and experience one of nature’s most vivid light shows,” Cooke said.
Eta Aquariids (May 5-6)
First up, on the night of May 5 and early hours of May 6, around 3:00 am CDT, is the eta Aquariid shower, caused by the annual encounter with debris from Halley’s comet – remnants of the comet’s tour through the solar system once every 75 or 76 years. Its radiant – or the point in the night sky from which the meteor shower appears to originate – is the constellation Aquarius. The shower is named for the brightest star in that constellation, eta Aquarii.
Until Halley’s comet is next visible from Earth in 2061, only the eta Aquariids – and their fall counterpart, the Orionid meteor shower, which is visible each October – mark the passage of this solar system visitor.
“It will be interesting to see if the rates are low this year, or if we will get a spike in numbers before next year’s forecast outburst,” Cooke said.
The annual meteor shower has the best rates for those in the Southern Hemisphere, but even in the Northern Hemisphere, if weather conditions are right, there is a possibility of seeing up to 30 meteors per hour. The waxing crescent Moon will set before the eta Aquariid radiant gets high in the sky, leaving dark skies for what should be an excellent show. Best viewing happens after 3 AM local time, so get up early.
Tau Herculids (May 30-31)
A possible newcomer this year is the tau Herculid shower, forecast to peak on the night of May 30 and early morning of May 31.
Back in 1930, German observers Arnold Schwassmann and Arno Arthur Wachmann discovered a comet known as 73P/Schwassmann-Wachmann, or “SW3, which orbited the Sun every 5.4 years. Being so faint, SW3 wasn’t seen again until the late 1970s, seeming pretty normal until 1995, when astronomers realized the comet had become about 600 times brighter and went from a faint smudge to being visible with the naked eye during its passage. Upon further investigation, astronomers realized SW3 had shattered into several pieces, littering its own orbital trail with debris. By the time it passed our way again in 2006, it was in nearly 70 pieces, and has continued to fragment further since then.
If it makes it to us this year, the debris from SW3 will strike Earth’s atmosphere very slowly, traveling at just 10 miles per second – which means much fainter meteors than those belonging to the eta Aquariids. But North American stargazers are taking particular note this year because the tau Herculid radiant will be high in the night sky at the forecast peak time. Even better, the Moon is new, so there will be no moonlight to wash out the faint meteors.
“This is going to be an all or nothing event. If the debris from SW3 was traveling more than 220 miles per hour when it separated from the comet, we might see a nice meteor shower. If the debris had slower ejection speeds, then nothing will make it to Earth and there will be no meteors from this comet,” Cooke 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.”
Skywatchers, you have the opportunity to see not just one, but two planetary conjunctions during the month of April 2022!
A conjunction is a celestial event in which two planets, a planet and the Moon, or a planet and a star appear close together in Earth’s night sky. Conjunctions have no profound astronomical significance, but they are nice to view. In our Solar System, conjunctions occur frequently between planets because the planets orbit around the Sun in approximately the same plane – the ecliptic plane – and thus trace similar paths across our sky.
The first planetary meet up occurs on the mornings of April 4 and 5 before sunrise and includes Mars and Saturn, with Saturn being the brightest. These two planets will come together, appearing as almost a single point of light. However, if you grab your binoculars, you’ll easily see the scene with the planets switching positions on each morning.
We will also see a bright Jupiter ascend quickly in the morning twilight, heading towards Venus in the final week of April. Catch a great view of the planets on the morning of April 27, which will include a waxing Moon.
Jupiter and Venus will then meet in conjunction during the morning of April 30 – appearing to nearly collide into each other. Due to the glare from both planets, observers will see them merge into one very bright, spectacular glow!
Venus’s orbit is closer to the Sun than the Earth’s, and Jupiter’s orbit is much farther away, so the proximity is an illusion, occurring only because Earth, Venus, and Jupiter happen to be approximately aligned. This celestial event will continue on the morning of May 1, but the positions of the planets, Jupiter and Venus, will be reversed.
If you want to know what else is in the sky for April, check out the latest “What’s Up” video from Jet Propulsion Laboratory:
Enjoy all this month has to offer as you watch the skies!
Did you know our planet has two types of seasons? They are meteorological and astronomical. What’s the difference?
“Meteorological seasons” follow the changing of the calendar, month to month, and are based on the annual temperature cycle – seasonal temperature variations modified by fluctuations in the amount of solar radiation received by Earth’s surface over the course of a year. For instance, the meteorological season of spring begins each year on March 1 and will end on May 31.
However, “astronomical” seasons happen because of the tilt of Earth’s axis (with respect to the Sun-Earth plane), and our planet’s position during its orbit around the Sun.
The March equinox – also called the vernal equinox – is the astronomical beginning of the spring season in the Northern Hemisphere. Seasons are reversed in the Southern Hemisphere where it will be autumn, also known as fall. These simultaneous seasons will occur March 20, 2022, at 15:33 UTC (Coordinated Universal Time) or 10:33 a.m. CDT (Central Daylight Time).
The Sun will pass directly above the equator, bringing nearly equal amounts of day and night on all parts of Earth. At the equator, an equinox results in about 12 hours of daylight and 12 hours of night.
Equinoxes and solstices are caused by Earth’s tilt on its axis and the ceaseless motion it has while orbiting the Sun. Think of them like events happening as our planet make its journey around the Sun.
North of the equator, the March equinox will also bring us earlier sunrises, later sunsets, softer winds, and budding plants. With the reversed season, those south of the equator will experience later sunrises, earlier sunsets, chillier winds, and dry, falling leaves.
If you’re in the Northern Hemisphere, watch the Sun as it sets just a bit farther north on the horizon each evening until the June solstice – when the Sun reverses directions, moving back to the south. Also, get outside to enjoy the warmer weather and extended daylight!
In meteorology, Earth’s winter season for the Northern Hemisphere and summer season for the Southern Hemisphere began on Dec. 1, 2021. However, the December solstice brings in the astronomical winter and summer seasons, respectively, for the two hemispheres of our planet. This will happen on Dec. 21 at 15:59 UTC, which is 9:59 a.m. CST in the United States.
Solstices come twice a year. For the Northern Hemisphere, the summer (June) solstice occurs around June 20-21, and the winter (December) solstice happens around Dec. 21-22. At the solstice, the Sun’s path appears farthest north or south, depending on which half of the planet you’re on. Seasons change on Earth because the planet is slightly tilted on its axis as it travels around the Sun.
Earth’s axis may be imagined as an imaginary pole going right through the center of our planet from “top” to “bottom.” Earth spins around this pole, making one complete turn each day. That is why we have day and night.
Although the tilt of the Earth as compared to the plane of its orbit around the Sun is more or less constant (23.5˚), at the December solstice, the Northern Hemisphere receives the most indirect sunlight, causing cooler temperatures. The Southern Hemisphere receives the most direct sunlight, causing warmer temperatures, so it is summer there. At the June solstice, this effect reverses and the Northern Hemisphere receives the most direct sunlight, causing warmer temperatures, and the Southern Hemisphere receives the most indirect sunlight, causing cooler temperatures.
The December solstice brings the shortest day and longest night of the year for locations in the northern half of the globe, like the U.S., while the southern half of the globe is experiencing its longest day and shortest night. Therefore, all locations north of the equator see daylight shorter than 12 hours and all locations south see daylight longer than 12 hours.
After the winter solstice in the Northern Hemisphere, the days will get longer and the nights shorter until the summer solstice on June 21, 2022, when things reverse. The March equinox on March 20, 2022, will mark the beginning of the astronomical spring season and the September equinox on September 22, 2022, will mark the beginning of astronomical fall.
The ancient cultures knew that the Sun’s path across the sky, length of daylight, and location of the sunrise and sunset all shifted in a regular way throughout the year. Additionally, people built monuments, like Stonehenge in England and the Torreon in Machu Picchu, Peru, to follow the Sun’s annual progress and predict its movements.
Today, we have even more information about the universe, and we celebrate the solstice as an astronomical event caused by Earth’s tilt on its axis and its motion in orbit around the Sun.
No matter where you are on Earth’s globe – this is your time to celebrate this seasonal change!
Every December we have a chance to see one of our favorite meteor showers – the Geminids. The shower is currently active until Dec. 17 and will peak on the night of Dec. 13 into the morning of Dec. 14, making those hours the best time for viewing the meteor shower.
The Geminids are caused by debris from a celestial object known as 3200 Phaethon, whose origin is the subject of some debate. Some astronomers consider it to be an extinct comet, based on observations showing some small amount of material leaving Phaethon’s surface. Others argue that it has to be an asteroid because of its orbit and its similarity to the main-belt asteroid Pallas.
Whatever the nature of Phaethon, observations show that the Geminids are denser than meteors belonging to other showers, enabling them to get as low as 29 miles above Earth’s surface before burning up. Meteors belonging to other showers, like the Perseids, burn up much higher.
The Geminids can be seen by most of the world. Yet, it is best viewed by observers in the Northern Hemisphere. As you enter the Southern Hemisphere and move towards the South Pole, the altitude of the Geminid radiant – the celestial point in the sky where the Geminid meteors appear to originate – gets lower and lower above the horizon. Thus, observers in these locations see fewer Geminids than their northern counterparts.
Besides the weather, the phase of the Moon is a major factor in determining whether a meteor shower will have good rates during any given year. This is because the moonlight “washes out” the fainter meteors, resulting in sky watchers seeing the fewer bright ones. This year, the Moon will be almost 80% full at the peak of the Geminids, which isn’t ideal for our highly regarded meteor shower. Nevertheless, that bright Moon is expected to set around 2:00 a.m. wherever you are located, leaving a couple of hours for meteor watching until twilight.
“Rich in green-colored fireballs, the Geminids are the only shower I will brave cold December nights to see,” said Bill Cooke, lead for NASA’s Meteoroid Environment Office, located at Marshall Space Flight Center in Huntsville, Alabama.
NASA will broadcast a live stream of the shower’s peak Dec. 13-14 via a meteor camera at NASA’s Marshall Space Flight Center in Huntsville, Alabama, (if our weather cooperates!), starting at 8 p.m. CST on the NASA Meteor Watch Facebook page.
Meteor videos recorded by the All Sky Fireball Network are also available each morning to identify Geminids in these videos – just look for events labeled “GEM.”
Learn more about the Geminids below:
Why are they called the Geminids?
All meteors associated with a shower have similar orbits, and they all appear to come from the same place in the sky, which is called the radiant. The Geminids appear to radiate from a point in the constellation Gemini, hence the name “Geminids.”
How fast are Geminids?
Geminids travel 78,000 mph (35 km/s). This is over 1000 times faster than a cheetah, about 250 times faster than the swiftest car in the world, and over 40 times faster than a speeding bullet!
How to observe the Geminids?
If it’s not cloudy, get away from bright lights, lie on your back, and look up. Remember to let your eyes get adjusted to the dark – you’ll see more meteors that way. Keep in mind, this adjustment can take approximately 30 minutes. Don’t look at your cell phone screen, as it will ruin your night vision!
Meteors can generally be seen all over the sky. Avoid watching the radiant because meteors close to it have very short trails and are easily missed. When you see a meteor, try to trace it backwards. If you end up in the constellation Gemini, there’s a good chance you’ve seen a Geminid.
Observing in a city with lots of light pollution will make it difficult to see Geminids. You may only see a handful during the night in that case.
When is the best time to observe Geminids?
The best night to see the shower is Dec. 13/14. Sky watchers in the Northern Hemisphere can go out in the late evening hours on Dec. 13 to see some Geminids, but with moonlight and radiant low in the sky, you may not see many meteors.
Best rates will be seen when the radiant is highest in the sky around 2:00 a.m. local time, including the Southern Hemisphere, on Dec. 14. The Moon will set around the same time. Therefore, observing from moonset until twilight on Dec. 14 should yield the most meteors.
You can still see Geminids on other nights, before or after Dec. 13-14, but the rates will be much lower. The last Geminids can be seen Dec. 17.
How many Geminids can observers expect to see Dec. 13/14?
Realistically, the predicated rate for observers in the northern hemisphere is closer to 30-40 meteors per hour. Observers in the Southern Hemisphere will see fewer Geminids than those in the northern hemisphere – perhaps 25% of rates in the Northern Hemisphere.
Although this year’s conditions are not the best for viewing the Geminid meteor shower, it will still be a good show to catch in our night skies.
And, if you want to know what else is in the sky for December, check out the video below from Jet Propulsion Laboratory’s monthly “What’s Up” video series:
LAUNCH UPDATE: NASA’s Laser Communications Relay Demonstration (LCRD) is now scheduled to lift off Tuesday, Dec. 7 at 3:04 a.m. CST (4:04 a.m. EST) aboard United Launch Alliance’s Atlas V rocket. Get more details here.
Have you ever witnessed one of NASA’s launches? It’s definitely a sight to see when a rocket takes to the sky, soaring beyond our atmosphere into space.
If you haven’t, you’ll have another chance soon with the Laser Communications Relay Demonstration (LCRD), which will continue NASA’s exploration of laser communications to support future missions to the Moon and throughout our solar system.
LCRD is scheduled to launch Dec. 5 aboard an Atlas V551 rocket from Cape Canveral Space Force Station in Florida with a two-hour launch window that opens at 3:04 a.m. CST (4:04 a.m. EST).
Live coverage of the launch begins on NASA Live at 2:30 a.m. CST (3:30 a.m. EST), with countdown commentary on NASA Television, the NASA app, and NASA social media.
Register as an LCRD virtual guest to experience NASA’s journey to the LCRD launch. Along with participating online in the launch, you’ll also gain access to curated launch resources, mission information, interaction opportunities, and schedule updates. Following launch, virtual guests will receive a stamp for their virtual guest passport!
Like technology demonstrations that have come before it, LCRD is a giant step towards making operational laser, or optical, communications a reality.
But just how much data can NASA transmit at once with laser communications? To give you an idea, sending a high-resolution map of Mars would take around nine weeks with spacecraft’s current onboard radio systems, but as little as nine days with laser communications. That kind of data rate is much more appealing for future human exploration and science missions.
With the mission operating for at least two years, LCRD will start off “talking” with ground stations in California and Hawaii to test the invisible, near-infrared lasers. Engineers will beam data to and from the satellite – located more than 22,000 miles above Earth – to study and enhance the technology’s performance for an operational mission. LCRD will also help NASA update how astronauts communicate to and from space.
As NASA goes back to the Moon, laser communications can empower sustainable communications and help us prepare for a human presence on Mars.
Developed and led by Goodard Space Flight Center in Greenbelt, Maryland, LCRD is funded by the Technology Demonstration Missions program, located at Marshall Space Flight Center in Huntsville, Alabama, which is part of the Space Technology Mission Directorate at NASA Headquarters in Washington. Additionally, it’s funded by the Space Communications and Navigation program, also at NASA Headquarters.