Skip to main content

Featured

Mars and Earth - Small difference & big consequences

Einstein's theory of relativity suggests that time is not a constant and can vary based on gravitational fields and speed. In a strong gravitational field, time moves slower compared to a weaker one. Since Mars has a weaker gravitational field than Earth, time actually flows slightly faster there.  This concept has implications for future space missions, as the timing of communication and operation of spacecraft will need to account for this difference in how time elapses on Mars compared to Earth. Missions may need to adjust their schedules, operations, and technology to ensure accuracy and synchronization with Earth. Basically, the moment you bring gravity and velocity into the picture, time stops behaving like the simple, universal tick‑tock we experience in everyday life. And you’re absolutely right: Mars’ weaker gravity means clocks there run a little faster than clocks on Earth. What’s fascinating is how small the difference is—and how big the consequences become ...

Simultaneous X-ray and infrared observations of the galactic center

The supermassive black hole (SMBH) at the center of our Milky Way galaxy, Sagittarius A*, is by far the closest such object to us, only about 25 thousand light-years away. Although not nearly as active or luminous as other SMBHs, its relative proximity provides astronomers with a unique opportunity to probe what happens close to the "edge" of a black hole. Monitored in the radio since its discovery and more recently in the infrared and the X-ray, Sgr A* appears to be accreting material at a very low rate, only a few hundredths of an Earth-mass per year. Its X-ray emission is persistent, probably resulting from the rapid motions of electrons in the hot accretion flow associated with the black hole. Once a day there are also flares of emission that are highly variable; they appear more often in the infrared than in X-rays. Some submillimeter wavelength flares have also been tentatively linked to IR flares, although their timing seems to be delayed with respect to infrared events. Despite these intensive observational efforts, the physical mechanisms producing flaring around this SMBH are still unknown and are the topic of intense theoretical modeling.

from Astronomy News - Space News, Exploration News, Earth Science News, Earth Science https://ift.tt/2U6XSaF

Comments

Popular Posts