Did Venus ever have an ocean?
The brief reply is: we don’t know. However the noble gases in Venus’ ambiance — helium, neon, argon, krypton, xenon and radon — may inform a narrative about water on the planet, and the way shortly it could have disappeared.
As a part of DAVINCI+’s mission, the spacecraft will drop a sphere via Venus’ ambiance to measure these non-reactive gases. Primarily based on what it finds, totally different ranges of noble gases may assist scientists flesh out their concepts about Venus’ past habitability and evolution.
“Noble gases and their isotopes — and the abundance of these isotopes — offer you a really clear indication of the inside properties of the planet,” Paul Byrne, a planetary geologist at NC State College, advised The Planetary Society. “The concept is that in the event you’re capable of measure the noble gasoline abundance and ratios of those totally different isotopes, you’ll be able to draw oblique — however vital — info.”
DAVINCI+’s investigation into Venus’ noble gases will elevate a bunch of questions. How a lot water would possibly Venus have began out with? How a lot of that water could have evaporated into the planet’s ambiance? Was Venus enveloped in magma, even in its early days? Or may some cataclysmic occasion have precipitated the planet’s carbon dioxide to flee into the ambiance, triggering a greenhouse impact?
We’ll have to attend and see what DAVINCI+ and VERITAS dig up.
What’s up with Venus’ volcanoes?
Regardless of being a really outdated planet, Venus is comparatively younger on the surface. Maps created by NASA’s Magellan spacecraft recommend that about 500 million years ago, the planet underwent some form of “resurfacing” that modified its exterior.
So what’s the key to Venus’ youthful glow after 4.5 billion years? It could possibly be volcanoes, however we will’t make certain. Though there’s proof that volcanism has performed an necessary position in Venus’ previous, we all know surprisingly little about current volcanic exercise on the planet. The truth is, energetic volcanism on Venus has by no means been straight imaged.
That is one space the place DAVINCI+ and VERITAS will likely be vital. They’ll tie collectively the story of Venus’ volcanoes, its noble gases and probably, its watery previous. VERITAS specifically will analyze the planet’s infrared floor emissions to seek for indicators of previous or current volcanic exercise. The mission may even catalog totally different rock varieties, which may level to extra proof of current or energetic volcanoes.
“An enormous query is: was there some form of catastrophic occasion, or extra ongoing, regular volcanism that was extra Earth-like?” NASA astronomer Sue Smrekar, VERITAS’ principal investigator, advised The Planetary Society. “We’ll be capable to decide what’s within the backside of 80% of the craters which have darkish flooring. Is it volcanism?”
Smrekar and her group may even seek for indicators of energetic volcanoes spewing out water. Such a discovery may utterly change our understanding of Venus’ inside.
“There’s this outdated concept that Venus’ inside is dry,” Smrekar mentioned. “However Venus seems to be much less outgassed than the Earth. It may have extra water in its inside than Earth.”
The place are Venus’ tectonic plates?
Venus is stuffed with unusual little surprises; regardless of being peppered with volcanoes, it doesn’t seem to have plate tectonics.
On Earth, lighter tectonic plates shift beneath heavier ones in a course of referred to as subduction, influencing each earthquakes and volcanoes. So how can Venus have so many volcanoes if it doesn’t have one of many key components to creating them?
Each DAVINCI+ and VERITAS will probe this query, however DAVINCI+ will take the first-ever high-resolution photos of among the planet’s most fascinating options: closely deformed areas referred to as tesserae.