Geminids: How Low Do They Go?

The Marshall Meteoroid Environment office put together the plot below showing the distribution of end heights of Geminids seen with our fireball camera network. 85% of Geminids burn up 40 to 55 miles above Earth’s surface and 15% get below 40 miles altitude.
 
Geminids penetrate deeper into the atmosphere than the Perseids because they are moving slower (78,000 mph for the Geminids compared to 130,000 mph for the Perseids) and are made up of denser material, owing to the fact that the Geminid parent body is rocky asteroid 3200 Phaethon and the Perseid parent is a comet yielding more fragile material.
 

This video shows meteors captured by a wide-field camera at the NASA Marshall Space Flight Center on the night of December 12. There are 141 events; at least 77 of these are Geminids, based on their angular speed and direction of travel. Near the end of the movie, a couple of satellites are visible crossing the field of view.

For those of us sky watching for meteors , this means we have a good chance of viewing a Geminid meteor. Tonight, December 13, into the early morning of December 14 is the peak. Happy meteor watching!

Behind the Scenes Team of a Web Chat

Ever wonder what it takes to pull together our web chat series? The chats usually consist of two components, live streaming and web chats.

The Automated Lunar and Meteor Observatory, or ALaMO, at NASA’s Marshall Space Flight Center in Huntsville, Ala., is where the live streaming component of “Watch the Skies” begins.

The ALaMO consists of two observatory domes, a 15 meter (50 ft.) tower with a roll-off roof, and an operations center with laboratory space. Inside the tower and one of the domes are 14′ Schmidt-Cassegrain telescopes equipped with focal reducers and astronomical video cameras. Once the roof rolls back or the dome opens up, the telescopes have easy access to the day and night skies.

The moment the telescopes or wide field astronomical video cameras are pointed, a fiber optic cable line is connected to the camera in order to send real time images to Marshall television.

Besides capturing footage and images for the web chats, the Schmidt-Cassegrain telescopes are used to observe the moon for lunar impact flashes. You can check out the current happenings about the lunar meteoroid impact monitoring at https://www.nasa.gov/centers/marshall/news/lunar/index.html 

Inside of Marshall’s NASA TV, our audio visual experts go to work uploading the live streaming to our online community group. With the click of a mouse users are able to see the live feed from the ALaMO.

Simultaneously, online users and NASA experts are tuned in with our online user community late nights to watch the skies together, via web chats. The Marshall public and employee communication team develops the information to promote the chat via nasa.gov and through social media. Additionally the communication team transcribes our expert’s answers to the chat room and moderates the chat.

Whether it is Venus in transit, meteor showers, or observing planets our NASA expert’s role is to answer questions from the public.  

Besides the web chats and contributing to the Watch the Skies blog series, the Meteoroid Environment Office’s daily work includes modeling meteor showers, analyzing lunar meteoroid impact data, and examining meteor observations.
 
For more insight into work done here at Marshall Space Flight Center’s Meteoroid Environment Office visit https://www.nasa.gov/offices/meo/home/index.html

The Automated Lunar and Meteor Observatory, or ALaMO, consists of two observatory domes, a 15 meter (50 ft) tower with a roll-off roof, and an operations center with laboratory space. (NASA)

Dr. Robert Suggs, manager of the ALaMO, checks one of the telescopes located in the observatory dome at the Automated Lunar and Meteor Observatory. The telescope is equipped with a focal reducer and astronomical video cameras. (NASA)

 

Meteor Over Texas

This morning at 6:43 AM Central Standard Time, eyewitnesses across Texas and adjacent states saw a very bright fireball streaking across the sky, moving roughly east to west. It was also recorded by a NASA meteor camera in Mayhill, New Mexico some five hundred miles to the West, which is very unusual and testifies to the brightness of the event. This was not the re-entry of Kosmos 2251, which was destroyed in a collision with an Iridium satellite in February 2009; it is a meteor, most likely a fragment from the asteroid belt and not associated with the Geminid meteor shower. 

Preliminary results indicate that there are meteorites from this meteor on the ground north of Houston, Texas–analysis is currently underway to refine the impact area. If pieces are recovered, it will be the 13th meteorite fall recorded in the state since 1909, and the first since Ash Creek, which fell in February of 2009.

A video (in Windows Media format) of the fireball as recorded by the NASA camera in New Mexico is attached to this message. The Moon is the bright object at lower center; the fireball is on the horizon at left and is surrounded by a white box when the camera detects it. Up is north, and left is east in the video.





 

 

Will We See A New Meteor Shower?

Some computer models indicate that the Earth may pass near decades old debris left behind by Comet Wirtanen in mid December, creating a new meteor shower. In the most optimistic scenario, viewers could see as many as 10-30 meteors per hour radiating from a point in the constellation Pisces in the early evenings, sometime between December 10 and 15. This time period also includes the peak of the strong annual Geminid meteor shower, so skywatchers have a chance of a “meteor night” after sunset on December 13; meteors from the new shower (if any) will be visible in the early evening, with the Geminids making their appearance later on and lasting until dawn.

Comet Wirtanen was discovered in 1948, just after World War II, and takes 5.4 years to orbit the Sun. It is a Jupiter family comet, with a perihelion (closest point to the Sun) just outside Earth’s orbit.

This graphic depicts the position of the constellation Pisces in the southwestern sky at 8 PM local time. The red dot shows the location of the radiant of the possible new meteor shower.

(Image credit: Bill Cooke/MSFC/MEO)

Bright Leonid Fireball


There are numerous reports of a bright fireball over northwest Alabama on Sunday, Nov. 18 at approximately 7:30 p.m. EST (6:30 p.m. CST). Southeastern cameras  managed by NASA’s Meteoroid Environment Office recorded the fireball, which was brighter than the moon.

(Credit: NASA/MFSC/MEO) 


(Credit: NASA/MFSC/MEO)

The image above is from the Marshall Space Flight Center camera. The moon is the bright object at the bottom right, and the fireball is the REALLY bright object. Even though this was a very bright fireball, the meteor fragmented too high in the atmosphere to produce meteorites on the ground — very spectacular, but nothing of substance survived.

Details for the fireball meteor:

Time: Sunday, Nov. 18, 7:29:25 p.m. EST (6:29:25 p.m. CST)
Speed: 28,400 mph
Direction: Roughly north to south

The fireball appeared 49 miles above the Alabama/Tennessee state line just  north of Athens, Ala. It disintegrated 28 miles above Ole Carriage Dr., just east of Athens. A map of the meteor trajectory appears below.

(Credit: NASA/MFSC/MEO)

This may very well be the brightest fireball we have seen with the Marshall Center camera!

Young Moon Sets Stage for Annual Leonids Meteor Shower

This year’s Leonids meteor shower peaks on Nov. 17 at 4:30 AM Eastern Time. If forecasters are correct, the shower should produce a mild but pretty sprinkling during the night of the 16th/morning of the 17th. The moon will be a waxing crescent setting before midnight, clearing the way for some unobstructed Leonid viewing. “We’re predicting a normal year of 15 to 20 meteors per hour” says Bill Cooke of the Meteoroid Environment Office at NASA’s Marshall Space Flight Center.

Leonids are bits of debris from Comet Tempel-Tuttle. Every 33 years the comet visits the inner solar system and leaves a stream of dusty debris in its wake. Many of these streams have drifted across the November portion of Earth’s orbit. Whenever our planet hits one, meteors appear to be flying out of the constellation Leo.

For best meteor viewing Cooke suggests going to a location away from city lights, dressing warmly, and lie flat on your back and look straight up. No special viewing equipment needed — just your eyes.

The Leonids occur each year in mid-November.

Leonid meteor storm of 1999 (NASA)

Leonids meteor shower as seen from Joshua Tree National Park in 2001 (Wally Pacholka/AstroPics.com)

Halloween Fireballs also known as Taurid Meteors are Upon Us

“Halloween fireballs” or Taurid meteors are frequently seen in the night sky from mid-October until mid-November. The Marshall all-sky camera network captured an image of an early Halloween fireball Tuesday morning. The fireball appeared low on the horizon from Huntsville at 6:10 a.m. Tuesday morning and was visible just above trees from the Tullahoma station.

“The bolide or fireball appeared some 44 miles above a point midway between the towns of Stanton and Mason, Tennessee and moved slightly north of east at a speed 3 times faster than that of the International Space Station.” said Dr. Bill Cooke, lead of Marshall Space Flight Center’s Meteoroid Environment Office in Huntsville, Ala.  “The fireball finally terminated above the town of Pinson, which is southeast of Jackson, TN.,” Cooke continued, “with an altitude at last visibility of 18.1 miles, which is fairly low for a meteor.”

Widely referred to as shooting stars, meteors are generated when debris enters and burns up in Earth’s atmosphere. Taurids are thought to be debris left behind by Encke’s comet.

Image credit:  NASA/MSFC

 

Look For The Harvest Moon This Weekend

Take a moment to gaze at the beautiful harvest moon this Saturday, September 29th.

(Image credit: NASA)

The harvest moon gets its name from agriculture. In the days before electric lights, farmers 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.

Northern summer changed to fall last Saturday, Sept. 22nd, and is called the autumnal equinox. The word equinox comes from the Latin words for “equal night.” The fall and spring equinoxes are the only days of the year in which the Sun crosses the celestial equator.

Keep an eye on the moon as it creeps above the eastern skyline. The golden sphere may appear inflated. This is the moon illusion at work. This optical illusion is caused by the moon’s proximity to distant objects. A harvest moon inflated by the moon illusion is simply beautiful to us, but even more so to the farmers getting their crops in on those cool autumn evenings.

(Image credit: Stefano De Rosa)

Once in a Blue Moon


Image credit: NASA/MSFC

On Aug. 31, if the night sky is clear, you will be able to see the second full moon of the month, which is called a “blue moon.”

You may have heard the expression, “once in a blue moon,” meaning “almost never,” because having 13 full moons in a calendar year — instead of the usual 12 — is rare.

Once in a blue moon, an individual who embodies the spirit of an explorer crosses the horizon in our culture. Such was Neil Armstrong. It is appropriate that the farewell to Armstrong coincides with the appearance of a blue moon.

A blue moon occurs just seven times every 19 years. The next blue moon will be on July 31, 2015.

Usually months have only one full moon, but occasionally a second one sneaks in. Full moons are separated by 29 days, while most months are 30 or 31 days long; so it is possible to fit two full moons in a single month. This happens, on average, every two and a half years.

So, as we say Godspeed to Mr. Armstrong, take a moment tonight to observe the blue moon, and give it a wink in honor of the first human to set foot on the surface of the moon.



Perseid Peak Performance

The All Sky camera network captured over 183 multi-station Perseid meteors Saturday night. Some truly spectacular events — see images below.

 The Perseids have been observed for at least 2,000 years and are associated with the comet Swift-Tuttle, which orbits the sun once every 133 years. Each year in August, the Earth passes through a cloud of the comet’s debris. These bits of ice and dust — most over 1,000 years old — burn up in the Earth’s atmosphere to create one of the best meteor showers of the year.