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 

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 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

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.