In 2013, in a big success story, a Mars rover and orbiter made a near-simultaneous observation of methane in Mars’ atmosphere. Now a newer mission orbiting Mars – ESA’s Trace Gas Orbiter – has failed to detect methane. Why?
Rain takes different forms on the planets and moons of our solar system. But it also “rains” on the sun, as electrified gas drips from giant magnetic loops in the sun’s outer atmosphere. Read about the sun’s coronal rain.
Einstein’s theory was confirmed in 1919, when British astronomer Sir Arthur Eddington measured the bending of starlight around the sun during a total solar eclipse. And it’s been re-confirmed since. How about now?
Solar physicists predict another weak 11-year solar cycle ahead. At the same time, they expect the coming cycle to break the trend of weakening solar activity seen over the past 4 cycles, and they add there’s “no indication we are currently approaching a Maunder-type minimum in solar activity.”
The star is a white dwarf, a cool, dead, dense star like our sun some 6 billion years from now. The planet fragment – made of heavy metals – survived a system-wide cataclysm that followed the star’s death.
Mars is a cold, dry desert, but a new study provides tantalizing evidence for liquid water deep below its surface. If it exists, this Mars groundwater might cause the weird dark streaks in Martian craters and canyons.
Dark matter theory – the idea that a huge fraction of our universe exists in a form we can’t see – is a cornerstone of modern cosmology. Ironically, galaxies lacking dark matter might help confirm the theory.