We know a lot about space, but there’s more we can’t explain… including these ten things that appear to defy science
1 AN UNEXPLAINED CLUMP OF DARK MATTER
Dark matter sounds ominous, but scientists believe that it comprises more than 80 per cent of all matter in the universe. It can’t be seen or directly detected because it doesn’t emit light or any type of radiation, but we’ve inferred its presence from how it affects objects that we can see. Typically, galaxies are surrounded by clouds of dark matter. Yet astronomers have found that a clump of dark matter located about 2.4 billion light years away appears to be all alone – no galaxies attached. Nearby galaxies collided and are now part of a merging galaxy cluster called Abell 520, but for some reason they left their dark matter behind.
The clump was first detected in 2007 by the Canadian Cluster Comparison Project (CCCP). The CCCP’s findings were reviewed by the Japanese Subaru telescope. Scientists were so puzzled that it was also part of a 2012 investigation by the Hubble Space Telescope, which confirmed that this clump of dark matter has been abandoned. However, additional research by a team at Ohio University found the ratio of dark to normal matter in the cluster to be normal. Clearly, further observations are needed to reveal the exact composition of Abell 520 and figure out how it formed.
2 THE MYSTERY SPEED BOOST
There’s a curious anomaly that happens when space probes conduct flybys over certain moons and planets in our Solar System: their speeds change slightly beyond what scientists expect. For example, when the Rosetta probe flew by Earth in 2005, it gained about 1.82 millimetres (0.07 inches) per second of speed, while in 1998 the Near Earth Asteroid Rendezvous (NEAR) spacecraft increased its velocity by 13 millimetres (0.5 inches) per second after an Earth flyby. Spacecraft use these flybys as a gravity assist, allowing them to gain momentum from the motion of a moon or planet in order to save fuel and reach their ultimate destinations faster. Rosetta, which also had help from the gravity of other celestial bodies, was on its way to observe comet 67P/ Churyumov–Gerasimenko.
They’re supposed to speed up, but the point is that they’re doing so by more than the expected amount. The numbers just don’t add up. Although a discrepancy of millimetres per second doesn’t seem to make much difference and hasn’t caused any problems, scientists want to figure out what’s causing it. We know that the flyby anomaly has occurred elsewhere, but we’re best able to measure it when it happens around Earth because of our monitoring stations. There are many hypotheses in the mix, including a halo of dark matter trapped by Earth’s gravity or the influence of magnetic fields, tides or solar radiation.
