Scientists have spent five decades sending spacecrafts to Mars in search of life. The missions to the Red Planet have successfully discovered the presence of methane on the planet. Now, Russia and the European Union have launched a new mission to see if methane’s presence could show there is life on Mars. The ExoMars Trace Gas…
New York, Oct 13: Astronomers have discovered that a Sun-like star lurking around 350 light-years away consumed the rocky equivalent of 15 Earths.
Dubbed Kronos after the child-eating Titan of Greek mythology, the star is the clearest and most dramatic case yet of a Sun-like star consuming its own planets, said Semyeong Oh, astrophysicist at Princeton University in New Jersey and lead author of the study.
“Even if our Sun ate the entire inner solar system, it wouldn’t come close to the anomaly we see in this star,” study co-author David Hogg from the Flatiron Institute in New York added.
The research did not begin as a hunt for a planet-eater.
Oh was analysing a catalog of new star data collected by the European Space Agency’s Gaia spacecraft for pairs of stars with similar speeds and trajectories.
Such duos are typically twin stars that formed close together from the same ingredients.
The analysis ultimately led to the identification of Kronos and its lesser known brother Krios.
Their official designations are HD 240430 and HD 240429, and they are both about 350 light years from Earth.
The keys to the discovery were first confirming that the widely separated pair are in fact a binary pair, and secondly observing Kronos’ strikingly unusual chemical abundance pattern, Oh explained in a statement released by the Princeton University.
Other co-moving star pairs have had different chemistries, Oh explained, but none as dramatic as Kronos and Krios.
Most stars that are as metal-rich as Kronos “have all the other elements enhanced at a similar level,” she said, “whereas Kronos has volatile elements suppressed, which makes it really weird in the general context of stellar abundance patterns.”
In other words, Kronos had an unusually high level of rock-forming minerals, including magnesium, aluminium, silicon, iron, chromium and yttrium, without an equally high level of volatile compounds — those that are most often found in gas form, like oxygen, carbon, nitrogen and potassium, the study said. (IANS)
- The science communities since a long time have been debating upon the existence of Planet Nine.
- Space highlights different shreds of evidence based on which scientists are stating the claim.
What Is Planet Nine?
Planet Nine is a hypothetical planet present in the far outer Solar System, whose mass is estimated to be 10 times more than the mass of Earth. The planet is said to be 20 times farther than the sun than Neptune is.
What Do Researchers Have To Say?
Dr Konstantin Batygin, a planetary astrophysicist at the California Institute of Technology, said that there were five different lines of observational evidence which pointed to the existence of Planet Nine. He stated that if this theory does not sound believable, then people would have to come up with the answers of the five pieces of evidence which could lead to further confusion.
Batygin in 2016 published a study examining the six known objects in the Kuiper Belt, a circumstellar disc in the Solar System beyond the planets that extends from the orbit of Neptune towards interstellar space.
The study examines all the objects have elliptical orbits pointing in the same direction and are tilted the same way. These serve as evidence to the planet’s existence.
It is being said that the objects are tilted 30 degrees downward compared to the plane where the eight official planets circle the sun. Researchers also made use of computer simulations of the solar system including the Planet Nine and to demonstrate that there should be more objects tilted a whopping 90 degrees to solar plane. It was revealed that five such objects, which fit these parameters were already known.
The study led to the birth of two more ideas. Researchers said that this planet could have tilted the planets of the solar system during the last 4.5 billion years.
Planet Nine’s existence could also tell the reason as to why Kuiper Belt objects orbit in the opposite direction as compared to other things in the solar system.
-Prepared by Megha Acharya of NewsGram.
(the story was originally published in PTI)
Washington, October 8, 2017 : After orbiting the Red Planet for 16 years, NASA’s Mars Odyssey spacecraft has captured its first images of the Martian moon Phobos.
The Thermal Emission Imaging System (THEMIS) camera on Mars Odyssey orbiter, launched in 2001, observed Phobos on September 29.
Phobos has an oblong shape with an average diameter of about 22 kilometres.
Cameras on other Mars orbiters have previously taken higher-resolution images of Phobos, but none with the infrared information available from THEMIS.
Observations in multiple bands of thermal-infrared wavelengths can yield information about the mineral composition of the surface, as well as the surface texture, NASA said in a statement this week.
“Although THEMIS has been at Mars for 16 years, this was the first time we have been able to turn the spacecraft around to look at Phobos,” said THEMIS Mission Planner Jonathon Hill of Arizona State University.
The researchers combined visible-wavelength and infrared data to produce an image color-coded for surface temperatures of this moon, which has been considered for a potential future human-mission outpost, NASA said.
“This half-moon view of Phobos was chosen because it allowed us to observe a wide range of temperatures on the surface,” Hill added.
One major question about Phobos and Mars’ even smaller moon, Deimos, is whether they are captured asteroids or bits of Mars knocked into the sky by impact.
The researchers believe that compositional information from THEMIS might help pin down their origin.
Since Odyssey began orbiting the Red Planet in 2001, THEMIS has provided compositional and thermal properties information from all over Mars, but never before imaged either Martian moon.
The September 29 observation was completed to validate that the spacecraft could safely do so, as the start of a possible series of observations of Phobos and Deimos in coming months.
“There is heightened interest in Phobos because of the possibility that future astronauts could perhaps use it as an outpost,” said Odyssey Project Scientist Jeffrey Plaut of NASA’s Jet Propulsion Laboratory in Pasadena, California. (IANS)