Spectacular photo of yesterday’s fireball over Groningen

October 14, 2009 17:11 by scibuff

Hundreds of reports flooded astronomical societies in the Netherlands and Germany yesterday, as people observed a brilliant fireball in the evening’s twilight skies. Below is a spectacular photo taken by Robert Mikaelyan.

Fireball Meteor Over Groningen - Source: Robert Mikaelyan

Extremely bright fireball seen over the Netherlands

October 13, 2009 19:34 by scibuff

Update 4: Below is a spectacular shot of the meteor captured by Robert Mikaelyan

Fireball Meteor Over Groningen captured around 17:00UTC on Tuesday Netherlands - Source: Robert Mikaelyan

Update 3: Koen Miskotte estimated the meteor’s brightness between -8 and -12.  According to his report the red orange fireball broke up in 5/6 pieces each one with a magnitude of -3 to -5. There are also reports of a sonic boom and a rumbling sound and shaking windows.

Update 2: Pictures of the smoke trail left by the bolide at dusk have appeared in a forum.

Update 1: According to the EXIF data of the original meteor photo, it was taken at 16:58:24 UTC between Assen and Groningen.

People in the Netherlands and Germany are reporting an extremely bright fireball seen around 19.00 CEST (17:00 UTC), traveling more or less south-north. Daniel Fisher of the Nuremberg Astronomical Association posted a photo of the meteor Daniel Fischer twittered links to a report posted on a mailing-list run by the Nuremberg Astronomical Association as well as to a a photo of the meteor:

A bright fireball seen over the Netherlands and Germany on October 13, 2009 at 16:58:24 UTC - Source: Jan de Vries

Theo Jurriens from the Kapteyn Astronomical Institute of University of Groningen, and KNMI – the Royal Netherlands Meteorological Institute, confirmed about one hundred reports received from the public. The meteor has been seen to burst into three pieces eventually.

Bolide smoke trail over the Dutch sky

Milky Way map from Gamma-ray to Radio

October 12, 2009 16:21 by scibuff

Chromoscope was originally created for the Royal Society Summer Science Exhibition 09 by Stuart Lowe, Rob Simpson, and Chris North. The main aim of Chromoscope is to provide a nice way to display images at different wavelengths by allowing you to fade between them (use the left/right arrows). A secondary aim is for the majority of the functionality to work without the need for an internet connection; the viewer can run on an offline computer. Only the search function requires an internet connection.

The sky with the Milky Way across the middle and the north pole of the Galaxy towards the top in Gamma-ray, X-ray, H-Alpha, Visible, Far-IR, Microwave and Radio

LCROSS impacts the Moon

October 9, 2009 11:44 by scibuff

Today at 11:31:19.5 UTC the Centaur upper stage impacted the lunar surface a 2.5km/s ejecting about 350 tonnes of lunar material into the path of the Shepherding Spacecraft which impacted about 4 minutes later at 11:35:38.7 UTC, ending thus the flight part of NASA’s LCROSS (Lunar CRater Observation and Sensing Satellite) mission. In the next few weeks, the impact ejecta will analyzed for the presence of hydrated minerals which would tell researchers if water is there or not.

Moon as viewed from the SSC about 30 minutes before Centaur impact - Source: NASA TV

Moon as viewed from the SSC about 20 minutes before Centaur impact - Source: NASA TV

Moon as viewed from the SSC about 10 minutes before Centaur impact - Source: NASA TV

Moon as viewed from the SSC at the time of Centaur impact - Source: NASA TV

Moon as viewed from the SSC about 1 minute before impact - Source: NASA TV

Silencing the crazy “Do not bomb the Moon” outcry

October 8, 2009 10:37 by scibuff

Tomorrow, the spaceflight part of NASA’s LCROSS (Lunar CRater Observation and Sensing Satellite) mission will end as the two main components, the Shepherding Spacecraft (S-S/C) and the Centaur upper stage rocket, impact the Cabeus crater located about 100km from the Lunar south pole.

An artist's impression of the LCROSS spacecraft's Centaur stage crashing into the surface of the Moon. The LCROSS spaceraft will observe and record the impact and then it also will crash into the crater - Image Credit: NASA

Immediately after the LRO/LCROSS launch on June 18, science illiterate members of the blog community started a campaign to stop NASA from “Bombing the Moon”; an act, which, according to them, was in a clear violation of the UN resolution 2222 written in the 1499th plenary meeting on December 19, 1966 – Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space, including the Moon and Other Celestial Bodies. I will not support this insanity by providing links here (just google “NASA Moon bombing”).

The arguments on blogs range from the creation of (up to) 8km deep crater, to the bombing constituting a hostile act against known extraterrestrial civilizations and settlements on the Moon allegedly observed by the crew of Apollo 11 (seriously?). Several magazines and newspapers (the likes of Scientific American, the Examiner and the UK Telegraph – no surprise there) jumped on the bandwagon featuring articles with an unfortunate (but I suspect a rather deliberate) word choice – “Moon bombing”.

Bombing can be defined as detonation (on impact) of an explosive devise producing a chemical action which causes a sudden formation of a great volume of expanded gas. In other words, nothing close to the events which are about to occur near the Moon’s south pole.

Let me assure you: the Moon is hit by space junk on regular basis. It has withstood this bombardment for billions of years and it will prevail for many billions to come. The flash in the sequence below was caused by a meteoroid about 25 cm in diameter traveling at 38 km/s. As such, although much smaller than either the (S-S/C) and the Centaur, the energy released in the impact is comparable with tomorrows impacts because this piece of rock was traveling fifteen times faster than LCROSS.

A meteoroid hits the Moon, May 2, 2006; video-recorded by MSFC engineers Heather McNamara and Danielle Moser.

The Centaur upper stage will impact the lunar surface at around 11:31:20 UTC at -84.675, 311.275 E (in selenographical coordinates). NASA estimates the impact velocity of 2.5 km/s which will excavate more than 350 tonnes of lunar material and create a crater 20m in diameter with a depth of about 4m; in other words, nowhere near the sensational 8km (given the crater size, not even the Hubble Space Telescope will be able to see it under ideal conditions).

Using the nominal impact mass of 2,305kg and the velocity of 2.5km/s the kinetic energy of the spacecraft can be easily calculated as

$E=\frac{1}{2}mv^{2}=0.5\times 2,503kg\times \left ( 2,500m\cdot s^{-1} \right )^{2} = 7,203,125,000\ J$

$E\simeq 7.2\times10^{9}\ J$

Since a kiloton of TNT is equivalent to $4.184\times10^{12}\ J$, the total energy released in the impact (under ideal conditions) is $0.001\ 72$ kiloton of TNT; again, nowhere close to the 2 kiloton of TNT (which equals to 10% of the yield of the bomb that destroyed Hiroshima) claimed by some authors. Furthermore, both the S-S/C and Centaur performed a blow-down maneuver to vent any remaining fuel inside the Centaur to help prevent contamination of the impact site and the ejecta material, thus there will be no explosion.

The Shepherding Spacecraft will impact the lunar surface roughly four minutes after the Centaur upper stage, at around 11:35:39 UTC at -84.729, 310.64 E, ejecting about 150 tonnes or material leaving behind a crater 14m wide and 2m deep.

LCROSS Shepherding Spacecraft and Centaur upper stage impact sites - Source: NASA

As for the last argument, if you truly believe in the conspiracy to cover up the presence of an extraterrestrial civilizations on the Moon, reported in witnessed statements by astronauts Buzz Aldrin and Neil Armstrong, and in witnessed statements to NSA (National Security Agency) photos and documents regarding an extraterrestrial base on the dark side of the Moon (let’s forget for a second that there is NO such thing as the “dark” side of the Moon), I applaud you for reading this far and let’s just leave it at that…

The sky in northern Michigan lit up by a spectacular meteor

September 3, 2009 10:17 by scibuff

Last night, fans at the Beach Bums game in Traverse City in Michigan reported seeing a bright meteor in the night sky.

“We were watching the game and then all of a sudden something caught our eyes.”
“We looked up really quick and there was this big, bright fireball… it seemed like it was right on top of us like you almost had to duck it seemed so low.”

There are also reports of a loud explosion, thus the object must have reached low enough altitudes where the air thickens enough that sound can propagate through it.

We thought someone set off dynamite – the boom shook the house.

This sighting adds to the series of bright meteors seen around the world recently. The number of similar reports in the last year should really be attributed to the rise of social media rather than increasing number of meteor activity. About 3,000 meteors are set ablaze in our atmosphere every day.

The space around us is filled with interplanetary debris. As of August 30, 2009, 6292 Near-Earth Objects (NEO) have been discovered. 1062 of these NEOs are asteroids with a diameter of approximately 1 kilometer or larger. Also, 145 of these NEOs have been classified as Potentially Hazardous Asteroids (PHAs).

Only yesterday, at 11:46:36 UTC the asteroid labeled as 2009 QC35, discovered by the Catalina Sky Survey on August 29, passed the Earth at a distance of about 0.0075 AU which roughly represents 2.9 Lunar Distances (LD). The separation of 1,113,500 km is considered quite close by space standards.

Orbit Diagram of 2009 QC35 - Source: NASA JPL

2009 QC35 has an estimated diameter of 23-52m. It is not one of the largest among Apollo asteroids (Earth-crossing NEOs with semi-major axis greater than 1.0 AU and perihelion distance less than 1.017 AU), nevertheless a collision with our planet would cause a great damage and leave a long lasting scar.

The Barringer Meteor Crater in Arizona created approximately 49,000 years ago by a nickel-iron meteorite with the diameter of about 50 meters