Russian research: Rocks found from object that caused Tunguska explosion

Andrei Zlobin of the Russian Academy of Sciences' Vernadsky State Geological Museum, claims in a paper he's uploaded to the preprint server arXiv, that he's found rocks he believe to be from the object that caused the Tunguska explosion over Siberia in 1908. 

If further analysis of the rocks confirms them to be from space, it will mark the discovery of the first physical evidence of the source of the famous blast.

The Tunguska Event, as it's known, was a very powerful explosion that occurred in the air over a part of Siberia near the Podkamennaya Tunguska River.

The force of it flattened forests for 2,150 square kilometers—it's considered to be the largest impact event in modern history.

Despite the immensity of the explosion, no debris from the object that caused it has ever been found—likely due to the remoteness of the impact zone and the political climate in Russia at that time.

Even more mysterious is the lack of an impact crater. Because of the dearth of evidence, there has been a lot of speculation about what caused the explosion, with the two most likely candidates being a meteoroid or a comet.

In his paper, Zlobin says he dug some holes in the permafrost in an area believed to be near the center of the impact zone, back in 1988.

He reports that he found nothing that could be tied to the explosion.

Before returning home, however, he collected some rock samples from the bottom of a shoal on the Khushmo River and brought them back with him to the museum.

Zlobin says he didn't sort or examine the rock samples until twenty years later.

He doesn't say so, but perhaps it was the hundred year anniversary of the Tunguska Event that spurred him into action—in any case, he found three samples that he believes came from outer-space.

He thinks so because they exhibit signs of both melting and ablations known as regmaglypts. Scientists believe the explosion was not hot enough to cause rocks on the ground to melt, thus, the melting of rocks in the area must have come as a result of the intense heat of passage through the Earth's atmosphere.

Zlobin says he believes the impact was caused by a comet, likely of a size close to Halley's Comet. Further testing of the rocks will need to be done to confirm they came from outer-space, of course.

If they come back positive, scientists will then have to debate amongst themselves whether they were part of the object that caused the Tunguska Event, or were a separate event altogether.

More information: Discovery of probably Tunguska meteorites at the bottom of Khushmo river's shoal, arXiv:1304.8070 [physics.gen-ph] arxiv.org/abs/1304.8070

NASA SDO Captures Image of Mysterious Object Refuelling From Sun [VIDEO]

Nasa's space telescope has caught footage of a mysterious object that was apparently flying in the plasma, close to the sun. The object appeared to have an extended tube that was connected to the sun.

Speculation that the object in the footage appeared like a huge planet, star or UFO is unlikely. The apparent extended tube does give the appearance that object is connected or 'refuelling' itself from the star's surface. The video was captured by Nasa's Solar Dynamics Observatory and put on YouTube.

Nasa has a more ordinary and scientific explanation for the strange, black orb. NASA Scientists believe that it is a solar "prominence" or "filament" - a feature extending from the sun which forms over the course of a day, and can extend hundreds of thousands of miles into space.

Scientists are still puzzled as to why these features form. The "dark" parts are cooler than the surrounding solar matter. There may be strong electro-magnetic forces at work.

C Alex Young, a solar astrophysicist at Nasa's Goddard Space Flight Centre, said: "Filaments appear to be dark because they're cooler in relation to what's in the background."

"When you look at it from the edge of the sun, what you see is this spherical object and you're actually looking down the funnel."

Kuiper Belt Researchers Study Object During A Stellar Occultation

First Team To Study A Kuiper Belt Object During A Stellar Occultation

Until now, astronomers have used telescopes to find Kuiper Belt objects (KBOs), moon-sized bodies, and obtain their spectra to determine what types of ices are on their surface.

They have also used thermal-imaging techniques to get a rough idea of the size of KBOs, but other details have been difficult to glean.

While astronomers think there are about 70,000 KBOs that are larger than 100 kilometers in diameter, the objects' relatively small size and location make it hard to study them in detail.

One method that has been has been proposed for studying KBOs is to observe one as it passes briefly in front of a bright star; such events, known as stellar occultations, have yielded useful information about other planets in the solar system.

By monitoring the changes in starlight that occur during an occultation, astronomers can determine the object's size and temperature, whether it has any companion objects and if it has an atmosphere.

The trick is to know enough about the orbit of a KBO to be able to predict its path and observe it as it passes in front of a star. This was done successfully for the first time last October when a team of 18 astronomy groups led by James Elliot, a professor of planetary astronomy in MIT's Department of Earth, Atmospheric and Planetary Sciences, observed an occultation by an object named "KBO 55636."

As Elliot and his colleagues report in a paper published to be published June 17 in Nature, the occultation provided enough data to determine the KBO's size and albedo, or how strongly it reflects light. The surface of 55636 turns out to be as reflective as snow and ice, which surprised the researchers because ancient objects in space usually have weathered, dull surfaces.

The high albedo suggests that the KBO's surface is made of reflective water-ice particles, and that would support a theory about how the KBO formed. Many researchers believe there was a collision that occurred one billion years ago between a dwarf planet in the Kuiper Belt known as Haumea and another object that caused Haumea's icy mantle to break into a dozen or so smaller bodies, including 55636.

More importantly, the research demonstrates that astronomers can predict occultations accurately enough to contribute to a new NASA mission known as the Stratospheric Observatory For Infrared Astronomy (SOFIA) that completed its first in-flight observations in May.