GabyIn microgravity, everything works differently. Flames become round, human bones lose density, and calluses on the feet disappear. Various liquids also behave strangely.
It is no coincidence that the team of forensic researchers became interested in how a changed gravitational environment will affect blood splatters and stains. How blood will interact with surfaces in such an environment and what patterns it will create. And in general – how microgravity will impact the future of forensics.
First experiments cosmic forensic experts
These questions marked the beginning of the first study of blood behavior in free flight. It laid the foundation for a new field of knowledge that scientists named “astrocriminology.”
Led by Professor Graham Williams from the University of Hull (UK), the team embarked on a flight aboard a parabolic research aircraft. The modified Boeing 727 from Zero Gravity creates short periods of microgravity through its up-and-down flight trajectory.
During a 20-second free fall, scientists projected drops of a blood substitute onto a sheet of paper. They then analyzed the resulting stains using standard terrestrial protocols. According to the participants in the experiment, although this concept seems simple, the team actually faced challenges in creating a safe and controlled environment for the experiments in an aircraft that was essentially falling to Earth during those 20 seconds. As a result, the research setup had to be securely fastened to the cabin. Interestingly, the experiments were conducted inside a repurposed pediatric incubator.
For the tests, scientists used a blood analog made up of 40 percent glycerin and 60 percent food dye, writes IFLScience This mixture has the same density and viscosity as human blood. And upon release, it leaves stains similar to those of real blood.
Ultimately, researchers discovered how microgravity affects blood behavior. On Earth, blood typically falls in a parabolic arc under the influence of gravity until it reaches the surface. However, in simulated space conditions, blood continued to move in a straight line until it reached the surface. This linear flight path is a striking example of inertia in action.
The second key observation was the smaller area of blood spread on the surface, the publication reported. Science Alert .
“In the absence of gravitational influence, surface tension and the adhesion of blood droplets are enhanced. This means that blood in space has a greater tendency to stick to surfaces… Blood droplets exhibit a slower spreading rate and, therefore, have shapes and sizes different from those on Earth,” noted Professor Graham Williams.
At the beginning of the experiment, the scientists also assumed that by eliminating gravity, they would achieve less uncertainty in their calculations. However, surface tension dominated to such an extent that the researchers encountered even greater variability in their estimates.
What is this needed for?
As noted by study co-author Zak Kowalski, PhD from Staffordshire University and an experienced criminologist, “studying the structure of blood stains can provide valuable reconstructive information about a crime or accident.” These initial steps of the new science of astro-criminology are very important for forensic investigations in space. Although it would be better if the results of this work were never put to the test in practice. Fortunately, there has not yet been any criminal offense in space.
Indeed, according to Mr. Kowalski, forensic medicine is more than just an attempt to solve crimes. It is extremely important for the reconstruction or analysis of technical malfunctions, for example, on board. International Space Station or shuttle.
The results of the study were published by the journal Forensic Science International: Reports.
