Space Agency Confirms Indonesia ‘Meteorite’

So, according to The Jakarta Post, last week’s ‘meteorite’ (these skeptical ‘quotes’ are getting ridiculous) that smashed down in East Jakarta, through the roof of a house, was in fact a meteorite. But this time, a scientist from the National Aeronautics and Space Agency (Lapan) has confirmed the original report to be true.

“The heat exposure showed that the object came with high speed and heat,” said Thomas Djamaluddin, an astronomy researcher.

According to another publication, the meteorite “was as big as a coconut.”

However, no meteorite remnants have been recovered from the scene. While it’s possible that the meteorite vaporized on impact, I strongly doubt there would be much of a house left after such an energetic blast.

Djamaluddin does point out that perhaps the meteorite had a “fragile structure,” a potential reason why there’s no fragments left. But that begs the question: If the meteorite was that fragile, could it really slam through the roof, destroy the second floor, explode, excavate a crater in the first floor and cause damage to two neighboring properties?

I’m not totally discounting the idea that this might have been a meteorite impact, but the evidence remains as sketchy as last week. So I’m sticking with my original thought that this “blast” was more likely terrestrial and not extraterrestrial in origin. But on the outside chance this was a meteorite, the neighborhood had a very lucky escape in that the space rock was big enough to cause significant property damage, yet small enough to stay contained.

Sources: The Jakarta Post, Antara News

Indonesia ‘Meteorite’ Wiped Out a House… Or Not.

A week after Israel played host to the amazing burning ‘meteorite’, another report is coming in about a ‘meteorite’ strike in East Jakarta, Indonesia. (Note the use of the famous ‘skeptical quotes’.)

On Thursday, a falling object crashed through the roof of a house causing moderate damage. There was also light damage to two adjoining properties. Fortunately, there are no reported injuries.

According to a report in the Jakarta Globe, there was a “blast” that resulted from the impact and there was a deep crater in the floor of the house. After creating the impact crater in the floor, the ‘falling object’ bounced.

I suspect the object impacted at high velocity, hit the floor, bounced back and hit the ceiling, then fell back down,” said a researcher from the Indonesian National Aeronautics and Space Agency (Lapan). “It’s extremely difficult to recover the fragments, what with the rubble and broken glass, and it being so dark in here.”

The article also states that there was evidence for a residual heat footprint and melted items around the crater. Apparently, these facts all point to evidence that a meteorite, or some man-made space junk, was involved.

Although the details are sketchy, there are a few points that concern me about this meteorite report:

First, if this ‘meteorite’ was large enough to create a “deep” crater (there’s no information about the crater’s approximate size), that would suggest it was a hyper-velocity impact. Not only is this kind of impact very rare, I doubt there would be anything left of the building.

Unless “moderate damage” means “there is no house left,” I strongly doubt the crater was caused by a meteorite.

Secondly, according to the Lapan scientist, the space rock “bounced.” While this is possible — take the Virginia meteorite that crashed through the roof of a doctors office, bouncing off the floor of an examination room, for example — if its impact was energetic enough to excavate a sizable crater (and produce a “blast”), then I doubt much of the meteorite would be left to “bounce.” It would have disintegrated, got lodged deep in the bottom of the crater, or not produced a crater at all.

Thirdly, the article states: “the residual heat footprint and melted items pointed to a meteorite.” As I’ve said before, meteorites are usually cold when they make landfall (assuming they are small enough to be slowed by our atmosphere), so this residual heat did not come from the meteorite. If the meteorite was large enough to slam into the house at hyper-velocity speeds, or hit a gas canister, then perhaps there might be some “residual heat.” But in this case, I strongly doubt there would be any house left.

Fourthly, according to Evan Irawan Akbar, from the Bosscha Observatory in Lembang, this event has occurred shortly after the Lyrid meteor shower which ended on Monday. So he rules out any connection. Which is fortunate, as this meteor shower is caused by the Earth passing through a harmless dust tail created by the periodic Comet C/1861 G1 Thatcher.

But then he drops this clanger: “It could, however, be part of the Eta Aquariid meteor shower, which peaks on May 7 and 8.”

The Eta Aquariid meteor shower is caused by dust trail from Halley’s Comet… last time I checked, dust grains from comets have never been linked with house-killing chunks of rock. Comets are made from ice and dust, stuff that easily burns up when hitting our atmosphere. These are meteor showers, not meteorite showers.

The extent of the damaged caused is also a little strange. From the article: “It blasted a hole in the second floor of the house, sending furniture falling to the first floor, and tore big holes in the walls.” Doesn’t that sound like an explosion?

Apparently the police have ruled out speculation that this was a gas canister explosion and although there is “no conclusive proof the damage was caused by a meteorite, it was the most likely explanation.”

Alas, meteorite impacts aren’t likely explanations, terrestrial explanations are the most “likely.” The fact that an Indonesian counter-terrorism squad has been dispatched to the area to look for traces of explosives suggest the authorities aren’t placing all their bets on this being a meteorite impact either.

Thanks to @antonwilliam for the tip!

Source: Jakarta Globe

First Images of LCROSS Centaur Impact Plume Released

The lunar dust plume as seen 15 seconds after Centaur impact. The size of the plume was approximately 6-8 km wide at this time (NASA)

The lunar dust plume as seen 15 seconds after Centaur impact. The size of the plume was approximately 6-8 km wide at this time (NASA)

Rising a mile high and up to 5 miles wide, the impact plume of the spent Centaur rocket was observed by the NASA LCROSS shepherding probe before it travelled through the cloud of dust and crashed 4 minutes later.

The lack of an observed dust plume has been the cause of much confusion to people who watched the events unfold in the early hours of October 9th. NASA publicised the impact event as if it was going to be an explosion of dust (and possibly ice), observable from telescopes on Earth. To say the mission finale was a disappointment is an understatement.

Following the impact, NASA responded by saying that although infrared images proved the Centaur crashed on target (and a 20 meter-wide crater was created), the lack of an accompanying plume could mean that the mass hit the side of a crater (therefore blasting debris at an angle), or it hit a region devoid of dust and water ice, or the plume was simply less obvious than expected. Now that NASA has released new images of the impact, it would appear the latter may be the case; the plume was just less spectacular than the promo videos depicted.

Nine instruments on board LCROSS captured impact sequence, but until now it was unknown whether an impact plume occurred. Now NASA has confirmed that an impact flash, plume and crater were all generated.

There is a clear indication of a plume of vapor and fine debris,” said Anthony Colaprete, LCROSS principal investigator. “Within the range of model predictions we made, the ejecta brightness appears to be at the low end of our predictions and this may be a clue to the properties of the material the Centaur impacted.”

So the number-crunching continues as we wait to find out whether water was contained within that plume. However, judging by the faint cloud of ejecta, I’m thinking dreams of a H2O reservoir in Cabeus crater might be short lived.

Source: NASA, LA Times. A special thanks to @jamerz3294 for the tip!

Mars Crater’s Cracked Frosting

Subliming ice from the crater's edge (NASA/JPL/University of Arizona)

Subliming ice from the crater edge (NASA/JPL/University of Arizona)

This image looks like the frosted top of an over-baked muffin, but it’s actually the side of a crater on Mars covered with ice. Taken by NASA’s Mars Reconnaissance Orbiter (MRO) High Resolution Imaging Science Experiment (HiRISE) over the Martian south pole, this example demonstrates an active process of weathering acting on the red landscape. According to the HiRISE site, the ice layer is approximately 3 km thick.

In regions situated closer to the equator, craters aren’t open to erosion by ice (not surface ice in any case), but in polar regions it’s a different story. Due to the Martian thin and cold atmosphere, water ice rarely melts into a liquid; it bypasses the liquid phase and turns straight into a gas. This process is known as sublimation. There are terrestrial examples of sublimation too, including frozen carbon dioxide (or “dry ice”) which sublimes at room temperature, generating a carbon dioxide vapour.

For this particular crater, it is obvious where there is a higher rate of sublimation than others. As the Sun illuminates the crater edge from the bottom right, the rim of the crater receives the most sunlight, heating up the darker regolith and causing more ice loss. The large cracked-like structure within the crater is most likely a combination of darker material under the ice receiving preferential heating and shrinkage of the subliming ice pack.

This seasonal freezing of water vapour and sublimation of water ice erodes the sides of these polar craters, wearing them down season after season.

I never tire of seeing HiRISE images of the Red Planet, especially when they include active atmospheric processes that continue to shape the landscape of this alien world.

Source: HiRISE