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Before yesterdayASTRO BIOLOGY

Scientists Find Molecular Patterns That May Help Identify Extraterrestrial Life

May 14th 2021 at 10:56

Scientists have begun the search for extraterrestrial life in the Solar System in earnest, but such life may be subtly or profoundly different from Earth-life, and methods based on detecting particular molecules as biosignatures may not apply to life with a different evolutionary history.

In Search Of Subsurface Oceans Within The Uranian Moons

May 13th 2021 at 23:24

The Galileo mission to Jupiter discovered magnetic signatures associated with hidden sub-surface oceans at the moons Europa and Callisto using the phenomenon of magnetic induction. These induced magnetic fields originate from electrically conductive layers within the moons and are driven by Jupiter's strong time-varying magnetic field.

Mars Astrobiological Cave And Internal Habitability Explorer (MACIE): A New Frontiers Mission Concept

May 13th 2021 at 00:03

Martian subsurface habitability and astrobiology can be evaluated via a lava tube cave, without drilling. MACIE addresses two key goals of the Decadal Survey (2013-2022) and three MEPAG goals.

Evidence That A Novel Type Of Satellite Wake Might Exist In Saturn's E Ring

May 12th 2021 at 23:37

Saturn's E ring consists of micron-sized particles launched from Enceladus by that moon's geological activity. A variety of small-scale structures in the E-ring's brightness have been attributed to tendrils of material recently launched from Enceladus.

New Marine Sulfur Cycle Model After The Snowball Earth Glaciation

May 12th 2021 at 00:42

The Sturtian Snowball Earth glaciation (717~660 million years ago) represents the most severe icehouse climate in Earth's history. Geological evidence indicates that, during this glaciation, ice sheets extended to low latitudes, and model simulations suggest global frozen ocean as well as a prolonged shut-down of the hydrological cycles.

Using DNA To Trace The Origins Of Giant Viruses

May 12th 2021 at 00:38

2003 was a big year for virologists. The first giant virus was discovered in this year, which shook the virology scene, revising what was thought to be an established understanding of this elusive group and expanding the virus world from simple, small agents to forms that are as complex as some bacteria.

How Planets Form Controls Elements Essential For Life

May 10th 2021 at 23:55

The prospects for life on a given planet depend not only on where it forms but also how, according to Rice University scientists.

First Discovery Of Methanol In A Warm Planet-forming Disk

May 10th 2021 at 23:52

An international team of researchers led by Alice Booth (Leiden University, the Netherlands) have discovered methanol in the warm part of a planet-forming disk.

Detection of Interstellar H2CCCHC3N

May 10th 2021 at 23:50

The chemical pathways linking the small organic molecules commonly observed in molecular clouds to the large, complex, polycyclic species long-suspected to be carriers of the ubiquitous unidentified infrared emission bands remain unclear.

Is Gravitational time dilation responsible for Dark Energy

Recently it has been suggested a force called Dark Energy is needed to account for the observations suggesting the universe’s expansion is accelerating. However, there is another reason which is related to effect gravity has on time.

Einstein told us and it has been observed the rate at which time passes is perceived to be slower in all environments where the gravitational potential is greater with respect where it is being observed. This means the further we look back in time, where the gravitational potential of the universe’s was greater due to the more densely pack matter, the estimate of its rate of expansion would be slower than it actually was if that were not taken into consideration.

However, we also know the gravitational potential has a slowing effect on the universe’s expansion and because that potential decreases as its volume increase, the rate of that slowing also decreases.

This means the rate of its expansion would be faster than it appeared to be from the perspective of present due to the effects gravity has on time while its actual rate of slowing would be declining due to its decreasing gravitational potential as it expands.

Yet, because of the non-linear effects between the slowing of time created by universe’s differential gravitational potential and the effects it has on its rate of expansion there will be a point in its history where one will APPEAR to overtake the other.


One could verify this conclusion by using the observation that about 4 billion years ago the universe’s expansion appears to have change from decelerating to an accelerated phase.Β This is because one could derive its actual rate of expansion in the past by using Einstein equations to determine how much time would have been slowed due to the differential gravitational potential between the past and present. If it was found that about 4 billion years ago that actual rate of expansion was faster than it is now it would suggest that the its expansion is NOT accelerating

Some may say the slowing of time slowing would not affect its expansion because it isΒ expanding along with the entire universe. However, Einstein define the time dilation only in terms of the affects a differentialΒ gravitational potential has on it therefore it would not be affected by its expansion. Some have also suggested that because it is expanding the gravitational potential is expanding and weakening at the same rate therefore when we look back the effects it will have on the timing of its expansion will cancel.Β Β  However, Einstein tells us the timing of events that cause the universe to expand is locked in the past along with its gravitational potential at the time the expansion took place. Therefore, one must take into account the differential gravitational potential between the past and present universe when defining its expansion.

Some have also suggested Relativistic properties gravity has on time already been already been accounted in the Friedman model that was used in part by scientist to define the accelerated expansion of the universe. However, that is NOT the case because when someone in the past measures its rate of expansion he or she would NOT need to use the slowing effects gravity has on time because his entire spatial slice of the universe would be at the same gravitational potential. However, this would NOT be the case for someone looking at it from the future. He would have to use it because due to its expansion a differential gravitational potential would have developed between the past and present. Yet as was mentioned earlier the effects gravity has on time tell us from the perspective of the present its expansion rate would be moving slower than it actually was from the perspective of someone who is present at the time when that expansion was taking place. In other words, since Friedman’s equation does not consider the effects the differential gravitational density has on time it would predict it to be slower in the past than it actually was.

The post Is Gravitational time dilation responsible for Dark Energy appeared first on Unifying Quantum and Relativistic Theories.

Probing The Icy Shell Structure Of Ocean Worlds With Gravity-topography Admittance

May 6th 2021 at 23:57

The structure of the icy shells of ocean worlds is important for understanding the stability of their underlying oceans as it controls the rate at which heat can be transported outward and radiated to space.

Grid of Pseudo-2D Chemistry Models for Tidally-Locked Exoplanets. I. The Role of Vertical and Horizontal Mixing

May 6th 2021 at 23:54

The atmospheres of synchronously rotating exoplanets are intrinsically three-dimensional, and fast vertical and horizontal winds are expected to mix the atmosphere, driving the chemical composition out of equilibrium.

Volcanoes On Mars Could Be Active, Raise Possibility of Recent Habitable Conditions

May 6th 2021 at 12:43

Evidence of recent volcanic activity on Mars shows that eruptions could have taken place within the past 50,000 years, a paper by Planetary Science Institute Research Scientist David Horvath says.

New Indicator For Oxygen levels In Early Oceans Developed

May 6th 2021 at 12:39

Oxygen is essential for the development of higher life. However, it was hardly present in the oceans of the young Earth. It was not until the evolution of photosynthetic bacteria that the oceans saw a significant increase in oxygen levels.

NASA Seeks Partners for the Astrobiology Science Conference

May 5th 2021 at 10:33

The Astrobiology Science Conference (AbSciCon) is a community-organized conference that provides a forum for reporting on new discoveries, sharing data and insights, advancing collaborative efforts and initiating new ones, planning new projects, and educating the next generation of astrobiologists.

Physics and Chemistry on the Surface of Cosmic Dust Grains: A Laboratory View

May 5th 2021 at 09:57

Dust grains play a central role in the physics and chemistry of cosmic environments.

Mass-radius Relationships For Irradiated Ocean Planets

May 5th 2021 at 09:53

Massive and water-rich planets should be ubiquitous in the universe. Many of those worlds are expected to be subject to important irradiation from their host star, and display supercritical water layers surrounded by extended steam atmospheres.

Using Geology To Help Astronomers Find Habitable Planets

May 5th 2021 at 09:51

Astronomers have identified more than 4,000, and counting, confirmed exoplanets -- planets orbiting stars other than the sun -- but only a fraction have the potential to sustain life.