International Observe the Moon Night 2021

Everyone, everywhere, every year is invited to celebrate with fellow Moon enthusiasts around our planet for International Observe the Moon Night – a worldwide public event encouraging observation, appreciation, and understanding of the Moon and its connection to NASA exploration and discovery.

Join NASA’s Marshall Space Flight Center on Oct. 16, 2021, for the Virtual Observation Party at 6:00 p.m. CDT via the Facebook event page.

observe the moon night
Image Credit: NASA/Vi Nguyen

This virtual event is brought to you by the Planetary Missions Program Office at Marshall and the U.S. Space & Rocket Center. Additionally, it will include a planetarium show and interviews with planetary and citizen scientists. There will also be an interview about the Artemis missions. So, don’t miss out on this fun, informative program!

It’s a great time to celebrate the Moon with people all over Earth as excitement grows about NASA returning to our nearest celestial neighbor with the Artemis missions. Artemis will land the first woman and first person of color on the Moon, using innovative technologies to explore areas of the lunar surface that have never been discovered before.

Since 2010, the celebration has occurred annually in September or October when the Moon is around first quarter – a great phase for excellent viewing opportunities.

Whether it’s outdoors, at home, online, or wherever you may be, you are encouraged to be a part of International Observe the Moon Night. Please remember to follow your local health and safety guidelines.

Learn more and find other events here. Enjoy the celebration!

by Lance D. Davis

How many Perseids will I see in 2021?

By Bill Cooke, NASA Meteoroid Environments Office

Many Perseid-related news stories and social media posts state that the maximum rate is about 100 meteors per hour, which is a lot. So, folks get excited and go out on the peak night, braving mosquitos and other nightly hazards. But they are often disappointed; we routinely hear, “I went out and only saw a few meteors. Not even 20, much less 100!” And they would be right. The problem is that the 100 per hour is a theoretical number used by meteor scientists and does not convey what people are actually going to see.

In the 1980’s, meteor researchers were searching for a way to compare the meteor shower rates observed by various individuals and groups across the globe. People were reporting the rates, but the differences in sky conditions, radiant altitude and observer eyesight made getting a comprehensive view of shower activity difficult.

So, the meteor researchers put their heads together and came up with the concept of a ZHR, or Zenithal Hourly Rate. The ZHR is what you get after you correct the observed rates for the sky conditions, the altitude of the radiant above the horizon and observer biases. In other words, it is basically what a perfect observer would see under perfect skies with the meteor shower radiant straight overhead – which never happens!

The often-quoted ZHRs overestimate the meteor rates people actually see – sometimes by a lot. Fortunately, we can take the ZHR and invert things to get the hourly rates for certain locations and circumstances – it’s only math, after all. We have done this for select locations in the United States, producing the following maps.

These maps show the hourly rates that can be expected on the night of the Perseid shower’s peak, provided there are no clouds in the sky. (It’s hard to account for partial cloud cover.)

These rates assume you are out in the country, where lots of stars and the Milky Way are visible and no clouds, of course:

Perseids in CountrySo, instead of 100 Perseids per hour, people in the U.S. can reasonably expect to see around 40-ish Perseids in the hour just before dawn on the peak nights. That’s about one every couple of minutes – not bad. However, we are assuming you are out in the country, well away from cities and suburbs.

What rates can you expect if you want to do your Perseid watching from the neighborhood? We also computed that:

Perseids in SuburbsThe brighter skies of the suburbs greatly cut down the rates. We have gone from a Perseid every couple of minutes to one every 6-7 minutes – a factor of three reduction. This explains the great disappointment expressed by many casual Perseid watchers; they go outside, expecting to see at least a meteor a minute and end up with 10 or less in an hour. The brightness of your sky is everything in meteor observing – you have to get away from the lights!

But what about those in cities? The rates are close to zero:

Perseids in CityUgh! City dwellers might see a Perseid or two in an hour. Not very inspiring. Perhaps the only good news is that, if someone in a city sees a Perseid, it has to be really, really bright and spectacular.

Want to see Perseids? Then head out into the dark – it’s worth it!

Check out our previous blog post, The Perseids are on the Rise, for more information on the Perseids and tips on how to observe them.

The Perseids are on the Rise!

It’s time again for one of the biggest meteor showers of the year! The Perseids are already showing up in our night skies—and when they peak in mid-August, it’s likely to be one of our most impressive skywatching opportunities for a while.

Perseid Meteor image
In this 30 second exposure taken with a circular fish-eye lens, a meteor streaks across the sky during the annual Perseid meteor shower on Friday, Aug. 12, 2016 in Spruce Knob, West Virginia. Photo Credit: (NASA/Bill Ingalls)

Our meteor-tracking cameras spotted their first Perseid on July 26, but your best chance to see them will start the night of Aug. 11. With the crescent moon setting early, the skies will be dark for the peak viewing hours of midnight (local time) to dawn on Aug. 12.

Perseid activity
This chart shows expected levels of Perseid activity for July and August 2021, relative to the peak on Aug. 11-13, ignoring the effects of the Sun, Moon, and clouds. All times are in UTC. Credits: (NASA/MEO/Bill Cooke)

If you’re in the Northern Hemisphere, and far away from light pollution, you might spot more than 40 Perseids an hour! (If you’re in a city, you may only see a few every hour; skywatchers in the Southern Hemisphere will also see fewer Perseids, with none visible below about 30 degrees south latitude.) The night of Aug. 12-13 will be another great opportunity to see the Perseids: with a full Moon (and lower meteor activity) during the Perseids’ peak in 2022 and a waning crescent high in the sky for 2023, this might be your best chance to do some summer skywatching for a few years.

Find somewhere comfortable, avoiding bright lights as much as possible (yes, including your phone), and give your eyes some time to adjust to the dark—up to half an hour if you can. The Perseids will appear as quick, small streaks of light: they get their name because they look like they’re coming from the direction of the constellation Perseus (near Aries and Taurus in the night sky), but Perseids in that area can be hard to spot from the perspective of Earth. So just look up and enjoy the show!

If you can’t see the Perseids where you live, join NASA to watch them on social media! Tune in overnight Aug. 11-12 (10 PM–5 AM CDT; 3–10 AM UTC) on Facebook, Twitter and YouTube to look for meteors with space fans from around the world. If skies are cloudy the night of Aug. 11, we’ll try again the same time on Aug. 12-13. Our livestream is hosted by the Meteoroid Environment Office at NASA’s Marshall Space Flight Center, which tracks meteors, fireballs, and other uncommon sights in the night sky to inform the public and help keep our astronauts and spacecraft safe.

Where do the Perseids *actually* come from?

The Perseids are fragments of the comet Swift-Tuttle, which orbits between the Sun and beyond the orbit of Pluto once every 133 years. Every year, the Earth passes near the path of the comet, and the debris left behind by Swift-Tuttle shows up as meteors in our sky. (Don’t worry, there’s no chance that we’ll run into the actual comet anytime soon.)

Where can I go to learn more?

We’ve got some great space-rock lessons for students, starting with the biggest question: what’s the difference between an asteroid and a meteor? Our NASA Space Place site also has a kid-friendly introduction to meteor showers in general. If you’re looking for something a little more hands-on, try this asteroid-building classroom activity—or, for an older audience, learn how to describe rocks like a NASA scientist.

And, if you want to know what else is in the night sky this month, check out the video below from Jet Propulsion Laboratory’s monthly “What’s Up” video series:

Happy skywatching!

by Brice Russ

See the Strawberry Moon – 2021’s Last Supermoon!

Our planet’s natural satellite – better known as the Moon – will appear opposite the Sun and fully illuminated on June 24, 2021, at 18:40 UTC, which is 1:40 p.m. CDT (UTC-5). This full Moon is quite special for two reasons: it’s a Strawberry Moon and the last supermoon of the year!

The Strawberry Moon marks the last full Moon of spring or the first full Moon of summer. Towards the end of June, the Moon usually sits in a lower position in the sky and shines through more of our atmosphere. Because of this, our Moon can sometimes give off a pinkish hue.

supermoon
A supermoon rises behind the U.S. Capitol, Monday, March 9, 2020, in Washington. Credits: NASA/Joel Kowsky

Surprisingly, the name likely has more to do with the time of the year it occurs than its unusual pink shade. Some Native American tribes referred to this full moon as the Strawberry Moon because it signaled a time for gathering ripening strawberries and other fruits.

A supermoon occurs when a full Moon coincides with the Moon’s closet approach to Earth in its elliptical orbit, a point known as perigee. During every 27-day orbit around Earth, the Moon reaches both its perigee, about 226,000 miles from Earth, and its farthest point, or apogee, about 251,000 miles from Earth.

Although supermoon is not an official astronomical term, it’s typically used to describe a full Moon that comes within at least 90% of perigee. In this phase, the Moon appears larger and brighter than usual. A new Moon can also be a supermoon. However, we typically do not see a new Moon since it is between Earth and the Sun, and therefore not illuminated.

If you’re in the daylight at the time of the Super Strawberry Moon, look for a better view during its moonrise, which is about 20 minutes after sunset, local time.

The Super Strawberry Moon will be the last of four supermoons for 2021. Supermoons only happen three to four times a year, and always appear consecutively. The last three supermoons occurred on May 26, April 27, and March 28.

Skywatchers, please enjoy the sunset in the west, and if you look toward the east, you may notice the subtle pink hue of our Super Strawberry Moon!

by Lance D. Davis

June Solstice Brings Summer, Winter Seasons

The June solstice gives us the green light to welcome the summer season in the Northern Hemisphere and winter season in the Southern Hemisphere. This happens June 21, 2021, at 03:32 UTC, but for us in North America, that’s June 20 at 10:32 p.m. CDT (UTC-5).

In meteorology, summer begins on June 1. Yet, June 21 is perhaps the most widely recognized day when summer starts in the northern half of our planet and winter starts in the southern half. This astronomical beginning of the summer season and long-held, universal tradition of celebrating the solstice have allowed us to treasure this time of warmth and light.

Summer solstice explanation
During the solstices, Earth reaches a point where its tilt is at the greatest angle to the plane of its orbit, causing one hemisphere to receive more daylight than the other. Credits: NASA/Genna Duberstein

Along with marking the beginning of summer, this will also be the longest day of the year in the Northern Hemisphere. We will begin to see early dawns, long days, late sunsets, and short nights. On the solstice, our Sun will reach its highest point as it crosses the sky. Meanwhile, south of the equator, winter will begin!

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, to follow the Sun’s annual progress, to worship the Sun, and to predict its movements.

Earth's seasons
Click to view larger. Credit: NASA/Space Place

Today, we celebrate the solstice as an astronomical event caused by Earth’s tilt on its axis and its motion in orbit 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, and why every part of Earth’s surface gets some of each.

Earth doesn’t orbit upright; its axis is always tilted 23.5˚ with respect to the Sun-Earth line, which is why we have seasons. During the June solstice compared to any other time of the year, the north pole is tipped more directly toward the Sun, and the south pole is tipped more directly away from the Sun. As a result, all locations north of the equator see days longer than 12 hours and all locations south see days shorter than 12 hours.

Enjoy the new season – whichever half of the globe you’re in!

by Lance D. Davis

Flights are Complete! Mission Success!

After two days of experimenting in weightlessness, a team of researchers from NASA’s Marshall Space Flight Center have their feet firmly planted on the ground.

The team spent April 28 and 29 on parabolic flights with ZERO-G in Fort Lauderdale, Florida. The flight — which achieves various levels of microgravity by performing maneuvers known as parabolas — provided the team with an opportunity to study the formation of potentially destructive amyloid fibrils, or protein clusters, like those found in the brain tissue of patients battling neurodegenerative diseases. The experiment, called the ring-sheared drop, was developed by Marshall and Rensselaer Polytechnic Institute of Troy, New York.

Marshall materials science engineer, Ellen Rabenberg, has supported the project for nearly five years. After two flights on ZERO-G’s modified Boeing 727 — G Force One — in 2016 and 2020, she supported the payload from the ground this year. As ground support, she was responsible for preparing and installing the equipment for flight.

parabolic flight on Flight Aware's live map
Marshall’s ground support team tracked the parabolic flight on Flight Aware’s live map while G Force One performed 30 parabolas. (Flight Aware)

To track the flight in real time, Rabenberg followed the live updates on Flight Aware. Over the course of approximately two hours each day, she monitored the map as G Force One completed 30 parabolas.

Now, Rabenberg and her colleagues will analyze the data gathered in flight and determine next steps for their payload.

Parabolic Pre-flight Checklist

How do you prepare for weightlessness? A team of researchers at NASA’s Marshall Space Flight Center has been doing so in preparation of their April 28 and 29 parabolic flights with ZERO-G in Fort Lauderdale, Florida.

Marshall's parabolic flight crew
The Marshall team exits the G Force One after the first day of parabolic flights. (NASA)
So what is on their parabolic pre-flight checklist?

An easily digestible breakfast
The flight team is served a doctor-recommended breakfast of bagels, fruit, and juice — all of which digest quickly and easily to provide fuel for their bodies as they experience periods of variable gravity.

Proper attire
Fort Lauderdale is a subtropical climate with warm and humid conditions in the spring. Participants wear light, comfortable clothing and closed toed shoes for movement in the hangar, on the ramp, and on the aircraft. Each flyer wears a ZERO-G flight suit, which enables ease of movement in air.

A COVID-19 test
All non-vaccinated participants are tested for COVID-19 daily to ensure safety of all parties.

Identification
Just like a typical commercial flight, each individual must complete a TSA check before boarding the aircraft. They must present a valid driver’s license, passport, or other TSA-approved identification.

Once all the pre-flight boxes are checked, the team will board a modified Boeing 727 — named G Force One — to execute their experiment in a weightless environment.

Marshall's flight team completes a TSA check before boarding G Force One.
Marshall’s flight team completes a TSA check before boarding G Force One. (NASA)

While in the air, the team will test an experiment known as the Ring-Sheared Drop. Developed by Marshall and Rensselaer Polytechnic Institute of Troy, New York, the experiment will study the formation of potentially destructive amyloid fibrils, or protein clusters, like those found in the brain tissue of patients battling neurodegenerative diseases — such as Alzheimer’s and Parkinson’s.

To track the flight path as it performs parabolas, check out Flight Aware.

For more updates on the flight, the team, and the experiment, continue to follow Watch the Skies blog in the coming week.

Sky Watching Highlights for February 2021

Do you want to see some sky watching highlights in February 2021? Find Mars all month after sunset, especially on the night of Feb. 18 for NASA’s planned rover landing. Then, watch the Moon glide across the Winter Circle before it pays a visit to the bright stars of the constellation Gemini. Check out the video below produced by NASA’s Jet Propulsion Laboratory to learn more!

 

Look for the Harvest Moon this Weekend

Take a moment this weekend to gaze at the beautiful Harvest Moon! The Moon will appear full Thursday night through Sunday morning. Early Saturday morning, Sept. 14, will mark the actual full Moon.

The Harvest Moon gets its name from agriculture. In the days before electric lights, farmers across the Northern Hemisphere depended on bright moonlight to extend the workday beyond sunset. It was the only way they could gather their ripening crops in time for market. The full Moon closest to the autumnal equinox became “the Harvest Moon,” and it was always a welcome sight.

The term became further entrenched in popular culture thanks to a 1903 pop tune called “Shine on Harvest Moon.”

A Harvest Moon inflated by the moon illusion — a common phenomenon with full moons seen close to the horizon, where familiar Earth objects such as trees or buildings lend the Moon a false sense of size — is simply beautiful to view, but even more so to the farmers gathering their crops in on those cool autumn evenings.

Perseids Peak August 11-13

The Perseid meteor shower is here! Perseid meteors, caused by debris left behind by the Comet Swift-Tuttle, began streaking across the skies in late July and will peak on the night of August 12.

The Perseid meteor shower is often considered to be one of the best meteor showers of the year due to its high rates and pleasant late-summer temperatures. This year’s shower, however, has unfortunate circumstance of having a full Moon right at the shower peak, reducing the meteor rates from over 60 per hour down to 15-20 per hour. But the Perseids are rich in bright meteors and fireballs, so it will still be worth going out in the early morning to catch some of nature’s fireworks.

Perseid meteor streaks over sky
A Perseid meteor over Daytona Beach, FL. Perseids are known for being bright and fast, traveling 132,000 mph. Image Credit: NASA/MEO

WHEN SHOULD I LOOK?

Make plans to stay up late or wake up early the nights of August 11 to 12 and August 12 to 13. The Perseids are best seen between about 2 a.m. your local time and dawn. On the night of the 11th, the Moon will set around 3 AM, giving you about an hour of dark sky to catch the shower. However, the rates will be lower than on the peak, so don’t expect more than 20 per hour, even without the Moon. On the night of the peak (August 12-13) you will only have a scant few minutes of dark sky between moon set and twilight – not much time to see Perseids.

If those hours seem daunting, not to worry! You can go out after dark, around 9 p.m. local time, and see Perseids. Just know that you won’t see nearly as many as you would had you gone out during the early morning hours.

How can you see the Perseids if the weather doesn’t cooperate where you are? A live broadcast of the meteor shower from a camera in Huntsville, AL (if our weather cooperates!) will be available on the NASA Meteor Watch Facebook starting around 8 p.m. ET and continuing until the early hours of August 13. Meteor videos recorded by the NASA All Sky Fireball Network are also available each morning; to identify Perseids in these videos, look for events labeled “PER.”

WHY ARE THEY CALLED PERSEIDS?

All meteors associated with one particular shower have similar orbits, and they all appear to come from the same place in the sky, called the radiant. Meteor showers take their name from the location of the radiant. The Perseid radiant is in the constellation Perseus. Similarly, the Geminid meteor shower, observed each December, is named for a radiant in the constellation Gemini.

Perseid meteor shower
Most of the meteors seen in this composite are Perseids. Notice how they all appear to be streaking from the same direction? The Perseids appear to radiate from a point in the constellation Perseus. Image Credit: NASA/MEO

HOW TO OBSERVE PERSEIDS

If it’s not cloudy, pick an observing spot away from bright lights, lay on your back, and look up! You don’t need any special equipment to view the Perseids – just your eyes.  (Note that telescopes or binoculars are not recommended.) Meteors can generally be seen all over the sky so don’t worry about looking in any particular direction.

While observing this month, not all of the meteors you’ll see belong to the Perseid meteor shower. Some are sporadic background meteors. And some are from other weaker showers also active right now, including the Alpha Capricornids, the Southern Delta Aquariids, and the Kappa Cygnids. How can you tell if you’ve seen a Perseid? If you see a meteor try to trace it backwards. If you end up in the constellation Perseus, there’s a good chance you’ve seen a Perseid. If finding constellations isn’t your forte, then note that Perseids are some of the fastest meteors you’ll see!

Pro tip:  Remember to let your eyes become adjusted to the dark (it takes about 30 minutes) – you’ll see more meteors that way. Try to stay off of your phone too, as looking at devices with bright screens will negatively affect your night vision and hence reduce the number of meteors you see!

Happy viewing!