Watch the Skies

Heads Up! Lyrid Meteor Shower Peaks April 22-23

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.

Lyrid Meteors from the Constellation Lyra – Image Credit & Copyright: Petr Horálek

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 more on meteors, visit the NASA Meteor Watch Facebook page.

The 2022 Geminids Meteor Shower Is Approaching

The cosmos’ annual gift to sky watchers, the Geminids Meteor shower, will peak on Dec. 13-14 this year.

During peak activity and perfect weather conditions, which are rare, the Geminids produce approximately 100-150 meteors per hour for viewing. However, this year a waning gibbous moon will make it harder to view most of the shower, resulting in only 30-40 visible meteors per hour at the peak in the Northern Hemisphere, depending on sky conditions. But the Geminids are so bright that this should still be a good show.

Bill Cooke, lead of NASA’s Meteoroid Environments Office at Marshall Space Flight Center in Huntsville, Alabama, suggests sitting in the shade of a house or tree while also maintaining a view of the open sky to alleviate moonlight interference.

The meteor shower is coined the Geminids because the meteors appear to radiate from the constellation Gemini. According to Cooke, meteors close to the radiant have very short trails and are easily missed, so observers should avoid looking at that constellation. However, tracing a meteor backwards to the constellation Gemini can determine if you caught a Geminid (other weaker showers occur at the same time).

Gemini does not appear very high above the horizon in the Southern Hemisphere, resulting in viewers only seeing approximately 25% of the rates seen in the Northern Hemisphere, which is between 7-10 meteors per hour. Sky watchers from the Southern Hemisphere are encouraged to find areas with minimal light pollution and look to the northern sky to improve their viewing opportunities.

A black circle has a series of white streaks which represent the geminid meteor shower. — Over 100 meteors are recorded in this composite image taken during the peak of the Geminid meteor shower in 2014. Credit: Jacobs Space Exploration Group/ESSCA

The Geminids start around 9 or 10 p.m. CST on Dec. 13, making it a great viewing opportunity for any viewers who cannot be awake during later hours of the night. The shower will peak at 6 a.m. CST on Dec. 14, but the best rates will be seen earlier around 2 a.m. local time. You can still view Geminids just before or after this date, but the last opportunity is on Dec. 17 – when a dedicated observer could possibly spot one or two on that night.

For prime viewing, find an area away from city and streetlights, bundle up for winter weather conditions, bring a blanket or sleeping bag for extra comfort, lie flat on your back with your feet facing south, and look up. Practice patience because it will take approximately 30 minutes for your eyes to fully adjust and see the meteors. Refrain from looking at your cell phone or other bright objects to keep your eyes adjusted.

The show will last for most of the night, so you have multiple opportunities to spot the brilliant streaks of light across our sky.

So where does this magnificent shower come from? Meteors are fragments and particles that burn up as they enter Earth’s atmosphere at high speed, and they usually originate from comets.

The Geminid shower originates from the debris of 3200 Phaethon an asteroid first discovered on Oct. 11, 1983, using the Infrared Astronomical Satellite. Phaethon orbits the Sun every 1.4 years, and every year Earth passes through its trail of debris, resulting in the Geminids Shower.

Phaethon is the first asteroid to be associated with a meteor shower, but astronomers debate its exact classification and origins. Phaethon lacks an icy shell (the staple characteristic of a comet), but some consider it a “dead comet” – suggesting it once had an icy shell that melted away. Other astronomers call it a “rock comet” because Phaethon passes very close to the Sun during its orbit, which theoretically results in heating and cracking that creates debris and dust. The bottom line is Phaethon’s exact origins are still a mystery, but we do know it’s the Geminids parent body.

Geminids travel 78,000 miles per hour, over 40 times faster than a speeding bullet, but it is highly unlikely that meteors will reach the ground – most Geminids burn up at altitudes between 45 to 55 miles.

An info graphic showing the altitude of the geminids based on 2019’s meteor camera data for the Geminids. — An info graphic based on 2019’s meteor camera data for the Geminids. Credit: NASA

In addition to sky watching opportunities, meteor videos recorded by the NASA All Sky Fireball Network are available each morning to identify Geminids in these videos – just look for events labeled “GEM.”

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:

Happy stargazing!

by Lane Figueroa

Last Chance to See Total Lunar Eclipse Until 2025!

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.

The Flower Moon lunar eclipse over NASA’s Michoud Assembly Facility in New Orleans is shown from the initial partial eclipse to totality in a composite of seven images shot on Sunday, May 15, 2022.
Image credit: NASA/Michael DeMocker

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.

A nearly total eclipse of a full moon that has a red shade to it. — A nearly total eclipse of November’s full “Beaver Moon” captured over the city of New Orleans before dawn on Nov. 19, 2021. The 97% eclipse clocked in at 3 hours, 28 minutes, and 24 seconds, making it the longest partial lunar eclipse in 580 years. Credits: NASA/Michoud Assembly Facility

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.

Gain more understanding of lunar eclipses, learn about NASA’s observations of eclipses, and inspire young stargazers with activities and information.

Finally, if you want to know what else is happening as you watch the skies in November, check out Jet Propulsion Laboratory’s latest “What’s Up” video:

Happy skywatching!

by Lane Figueroa

September Equinox Marks the Start of Fall 2022

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.

An illustration of the March (spring) and September (fall or autumn) equinoxes. During the equinoxes, both hemispheres receive nearly equal amounts of daylight. (Image not to scale) Credits: NASA/GSFC/Genna Duberstein

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.”

A visual aid to better understand how the Earth's tilted axis causes the different seasons throughout the year in the Northern and Southern Hemispheres. — A visual aid to better understand how the Earth’s tilted axis causes the different seasons throughout the year in the Northern and Southern Hemispheres. Credit: NASA/Space Place

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.

by Lane Figueroa

Jupiter to Reach Opposition, Closest Approach to Earth in 59 Years!

Stargazers can expect excellent views of Jupiter the entire night of Monday, Sept. 26 when the giant planet reaches opposition. From the viewpoint of Earth’s surface, opposition happens when an astronomical object rises in the east as the Sun sets in the west, placing the object and the Sun on opposite sides of Earth.

Jupiter’s opposition occurs every 13 months, making the planet appear larger and brighter than any other time of the year. But that’s not all. Jupiter will also make its closest approach to Earth since 1963 – almost six decades ago! This happens because Earth and Jupiter do not orbit the Sun in perfect circles – meaning the planets will pass each other at different distances throughout the year. Jupiter’s closest approach to Earth rarely coincides with opposition, which means this year’s views will be extraordinary. At its closest approach, Jupiter will be approximately 367 million miles in distance from Earth, about the same distance it was in 1963. The massive planet is approximately 600 million miles away from Earth at its farthest point.

Photo of Jupiter with Red Spot — This photo of Jupiter, taken from the Hubble Space Telescope on June 27, 2019, features the Great Red Spot, a storm the size of Earth that has been raging for hundreds of years. Credits: NASA, ESA, A. Simon (Goddard Space Flight Center), and M.H. Wong (University of California, Berkeley)

“With good binoculars, the banding (at least the central band) and three or four of the Galilean satellites (moons) should be visible,” said Adam Kobelski, a research astrophysicist at NASA’s Marshall Space Flight Center in Huntsville, Alabama. “It’s important to remember that Galileo observed these moons with 17th century optics. One of the key needs will be a stable mount for whatever system you use.”

Kobelski recommends a larger telescope to see Jupiter’s Great Red Spot and bands in more detail; a 4 inch-or-larger telescope and some filters in the green to blue range would enhance the visibility of these features.

According to Kobelski, an ideal viewing location will be at a high elevation in a dark and dry area.

“The views should be great for a few days before and after Sept. 26,” Kobelski said. “So, take advantage of good weather on either side of this date to take in the sight. Outside of the Moon, it should be one of the (if not the) brightest objects in the night sky.”

As the Moon rose over the Wasatch Mountains near Salt Lake City on Feb. 27, 2019, the planet Jupiter could be seen, along with three of its largest moons. Stargazers should have a similar view during Jupiter in Opposition on Monday, Sept. 26. Credits: NASA/Bill Dunford

Jupiter has 53 named moons, but scientists believe that 79 moons have been detected in total. The four largest moons, Io, Europa, Ganymede, and Callisto, are called the Galilean satellites. They are named after the man who first observed them in 1610, Galileo Galilei. In binoculars or a telescope, the Galilean satellites should appear as bright dots on either side of Jupiter during opposition.

NASA’s Juno spacecraft, which has been orbiting Jupiter for six years, is dedicated to exploring the planet and its moons. Juno began its journey in 2011 and reached Jupiter five years later. Since 2016, the spacecraft has provided incredible images and data about Jupiter’s lively atmosphere, interior structures, internal magnetic field, and magnetosphere.

Scientists believe studying Jupiter can lead to breakthrough discoveries about the formation of the solar system. Juno’s mission was recently extended until 2025 or until the end of the spacecraft’s life. Learn more about Juno.

The next major project for Jupiter exploration is the Europa Clipper. This spacecraft will explore Jupiter’s iconic moon, Europa, which is known for its icy shell and vast ocean that lies beneath its surface. NASA scientists aim to find whether Europa has conditions able to sustain life. Europa Clipper’s targeted launch is currently scheduled for no earlier than October 2024.

Learn more about the giant planet. And if you want to know what else is happening in the sky for September, check out Jet Propulsion Laboratory’s latest “What’s Up” video:

by Lane Figueroa

Fireball lights up the sky over Salt Lake City

A bright meteor flew through the skies over northern Utah on Saturday morning, later raining down meteorites over the Great Salt Lake.

Residents of the Salt Lake City area were startled by loud booms at 8:30 a.m. MDT on Saturday, Aug. 13, 2022. Eyewitnesses saw a fireball in the sky, 16 times brighter than the full Moon.

GOES 17 Geostationary Lightning Mapper detection of the Aug. 13, 2022, fireball over northern Utah. Credits: NOAA

Approximately 22,000 miles out in space, NOAA’s Geostationary Lightning Mappers (GLM) onboard the Geostationary Operational Environmental Satellites (GOES) 17 and 18 detected the meteor, which was first seen 50 miles over West Valley City. However, it is difficult to pinpoint its exact trajectory.

“Daytime fireballs are very tough to analyze,” said Bill Cooke, lead of NASA’s Meteoroid Environments Office at Marshall Space Flight Center in Huntsville, Alabama. “There are few eyewitness sightings of the fireball and videos posted on social media are difficult to calibrate without stars in the background.”

The meteor was first seen 50 miles over West Valley City, Utah, moving to the northwest at 39,000 miles per hour. The object broke apart above the eastern shore of the Great Salt Lake. Credits: NASA

After traveling northwest at 39,000 miles per hour, the object – a piece of an asteroid about 2 feet across – broke apart above the eastern shore of the lake. “One meteorite has been recovered from the lake shore,” said Cooke. “There are probably more, but I would expect the vast majority fell into the water.”

NASA studies meteoroid environments in space to protect astronauts and satellites in space. NASA’s Meteoroid Environment Office prepares meteoroid forecasts for missions like Artemis I, the first integrated test of NASA’s deep space exploration systems: the Orion spacecraft, Space Launch System rocket, and the ground systems at Kennedy Space Center in Cape Canaveral, Florida. The Artemis I launch is currently targeted for Aug. 29.

For more information on NASA’s All Sky Fireball Network, visit:

https://fireballs.ndc.nasa.gov

To follow and share meteor updates, visit:

https://www.facebook.com/NasaMeteorWatch

By Hannah Maginot

Saturn to Reach Opposition Aug. 14

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.

An illustration of NASA's Cassini spacecraft in orbit around Saturn, where it documented the ringed planet in 2017. — An illustration of NASA’s Cassini spacecraft in orbit around Saturn, where it documented the ringed planet in 2017. (NASA/JPL-Caltech)

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.

Learn more about Saturn here.

by Rick Smith

Perseids Meteor Shower on the Way

The Perseids are back! Well… sort of.

Usually bringing one of the most vivid annual meteor showers visible in Earth’s night sky, commonly delivering 50-100 “shooting stars” per hour at its height, the Perseids will peak Aug. 12 and 13. There’s just one problem: the full Moon.

A shower of Perseid meteors lights up the sky in 2009 in this NASA time-lapse image. (NASA/JPL)

“Sadly, this year’s Perseids peak will see the worst possible circumstances for spotters,” said NASA astronomer Bill Cooke, who leads the Meteoroid Environment Office at NASA’s Marshall Space Flight Center in Huntsville, Alabama. “Most of us in North America would normally see 50 or 60 meteors per hour,” he said, “but this year, during the normal peak, the full Moon will reduce that to 10-20 per hour at best.”

The Moon is so much brighter than anything else in the night sky, and it will wash out all, but the very brightest Perseids as they streak through our atmosphere and burn up far overhead.

As the full Moon subsides, the Perseids will begin to wane Aug. 21-22 and cease completely by Sept. 1. They’re the debris remnants of Comet Swift-Tuttle, a lumbering “snowball” composed of ice, rock, and dust, which orbits our Sun every 133 years. The comet itself was last visible to us in 1992 and won’t pass our way again until 2125.

How far back sightings of the Perseids actually go remains a matter of some contention, Cooke said. The comet itself wasn’t identified until 1862, but the meteor shower was seen over medieval Europe. The annual event came to be known as “the Tears of St. Lawrence,” named for the last of seven Roman church deacons martyred by the emperor Valerian in August of the year 258.

So, this is probably not the best year to make a special trip in order to see the Perseids, but, if you find yourself outside between midnight and dawn on Aug. 13, don’t forget to look up anyway. Because you never know – you might just catch one of the bright Perseid meteors that defies the glare of the Moon. Also, the occasional early Perseid can streak across the sky as much as a week beforehand.

If you want to know what else is in the sky for August, check out the latest “What’s Up” video from Jet Propulsion Laboratory:

by Rick Smith

New meteor shower? How many meteors will I see, really?

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.”

This infrared image from NASA's Spitzer Space Telescope shows the broken Comet 73P/Schwassman-Wachmann 3. — This infrared image from NASA’s Spitzer Space Telescope shows the broken Comet 73P/Schwassman-Wachmann 3 skimming along a trail of debris left during its multiple trips around the sun. The flame-like objects are the comet’s fragments and their tails, while the dusty comet trail is the line bridging the fragments. (Credit: NASA)

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.

Mars-Jupiter Conjunction Visible May 29

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.

Sky chart showing how Jupiter and Mars will appear in the pre-sunrise sky on May 28-30. Credits: NASA/JPL-Caltech

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!

By Rick Smith