NASA and ESA are sending three new missions to Venus in the coming decade. NASA's VERITAS
and DAVINCI+, along with ESA's EnVision, will set out to discover how a planet that was
once a twin of Earth's transformed into the desolate inferno it is today.
Welcome to Launch Pad, I'm Christian Ready, your friendly neighborhood astronomer. NASA's
new administrator, Bill Nelson, announced that not one but two new missions to Venus
were selected as the newest of NASA's discovery class missions. When they launch around 2030
DAVINCI+ and VERITAS will mark NASA's return to Venus in about 40 years.
But if that weren't cool enough, ESA just announced its EnVision mission will head to
Venus at around the same time. So today we're going to take a look at these three new missions
and what they may tell us about our sister planet.
But if you'd like to learn more about why scientists think that Venus may have once
been habitable, then I invite you to check out a series of documentaries about Venus
on Magellan TV who are very kindly sponsoring today's video.
Magellan is a documentary streaming service featuring content on history, art, nature
and space and science. They're E'xploring. Venus' series delves into why astronomers
believe it was once and may still be a habitat for life. Other documentaries investigate
how we may explore and even colonize Venus someday.
And now you can get a full year of Magellan TV for 30 percent off. That's just $3.50 a
month! And this offer is available to both new and returning subscribers alike. So please
make sure to use the link in the description of this video.
NASA hasn't sent a dedicated mission to Venus since the Magellan spacecraft in 1989, and
it hasn't directly sampled its atmosphere since Pioneer Venus in 1978. That's not to
say that humanity in general hasn't dropped by in the intervening years.
Japan's Venus Climate Orbiter, Akatsuki and ESA's Venus Express are relatively recent
orbiters, and the Soviet Union's Venera and Vega programs made several landings on the
planet in the 1970s and 80s. But overall, Venus hasn't seen quite as much love as other
terrestrial planets.
And that's a shame because Venus is one of the most enigmatic planets in the solar system.
It's a near identical twin of Earth with similar mass radius and density. If you could stand
on Venus, you'd only weigh about 10 percent less than you do here on Earth.
Not that you'd survive or anything, because despite being Earth's twin in a global sense,
Venus couldn't be any more different from Earth. It's permanently enshrouded in thick
clouds of carbon dioxide and sulfuric acid. Its atmosphere is trapped so much heat that
any oceans that once had boiled away long ago.
As a result, temperatures on the surface reach 900 degrees Fahrenheit. That's hot enough
to melt lead the atmosphere so thick that surface pressures are 93 times greater than
sea level on Earth. That's about the same pressure as nine hundred meters or three thousand
feet under water at that pressure.
The air is a supercritical fluid. It's not a liquid, but not really a gas either. It's
so thick you'd have to push against the air just to walk around in your air conditioned
hard suit. Given these conditions, it's not surprising that the Soviet Venera Landers
could only operate for a couple of hours on the surface before flying
out. And yet it seems that Venus wasn't always like this. There's considerable evidence to
suggest it was once very Earthlike with normal temperatures and oceans of water. So what
happened? Well, Venus is closer to the Sun and the Sun has brightened over the last four
and a half billion years.
And that would have raised its temperature, which led to Venus runaway greenhouse effect.
But NASA's Magellan orbiter found that there's a lot more to the story. Since Venus is shrouded
by a permanent layer of sulfuric acid clouds, Magellan used radar to map the terrain.
Remarkably, Magellan didn't find any evidence that Venus' crust is fractured into tectonic
plates. By contrast, Earth's crust is separated into large plates that move about on top of
the mantle. Carbon dioxide, sulfur dioxide and other greenhouse gases rain down to the
surface and settle into the rocky crust.
Convection from the interior churns the mantle, causing the plates to collide and dive under
each other in a process called subduction. This drives the carbon deep into the mantle,
keeping it out of the atmosphere. Magellan found that Venus seems to lack any evidence
of these large scale tectonic plates.
But Magellan did find that 85 percent of the crust is covered in lava flows with relatively
few craters. And then there are these huge swaths of wrinkled terrain called Tesserae.
And these are the weirdest features on Venus. They're rough, bright texture implies some
kind of tectonic activity, but exactly what kind is unknown. It's possible these are preserved
subduction zones, perhaps from early plate tectonics. Magellan gave us our first maps
of the surface, but left us with so many unanswered questions. For example, did Venus have active
plate tectonics in the past?
If so, when did it shut down, and why? Is Venus still geologically active today with
erupting volcanoes and other tectonic activities, or is it completely dead? Fortunately, technology
has come a long way since the 1980s when Magellan was built.
So it's about time that we went back. VERITAS and DAVINCI+ are the latest selections of
NASA's discovery program. These are focused missions that can be developed quickly at
a lower cost and larger flagship missions. DAVINCI+ stands for Deep Atmosphere Venus
investigation of Noble Gases, Chemistry and imaging Plus. The "plus" is due to improvements
over the original DAVINCI proposal in 2015. The spacecraft will make two flybys of Venus
in 2030. It will carry a suite of four cameras called VISOR for Venus Imaging System from
Orbit for Reconnaissance.
One of the VISOR cameras will be sensitive to ultraviolet light to track cloud motions
in the atmosphere. The remaining three cameras will pick up the near infrared emission coming
from the surface. These reconnaissance observations will identify the overall composition of different
regions of the planet, and this will help determine how ancient oceans may have shaped
the surface.
When DAVINCI+ makes a third return to Venus the following year, it will drop the DAVINCI
probe into the atmosphere. The probe is a spherical titanium pressure vessel packed
with instruments that will analyze the Venusian atmosphere, starting from the cloud tops all
the way down to the surface.
Along the way, it's imaging system will acquire high resolution 3D images of the Alpha Regio
mountains. These mountains have intriguing features that could reveal details about the
planet's geologic history. The DAVINCI mission was proposed long before the announcement
of Phosphine in Venus's atmosphere. On Earth, phosphine is created naturally by biological
processes. Since the upper atmosphere of Venus has shirtsleeve temperatures and sea level
pressures, the phosphine detection begs the question if Venus may still hold bacterial
life in its atmosphere. Now, I made a video about that, so I won't repeat all the details
here.
But since that initial announcement, the amount of phosphine present appears to be much less
than originally determined. DAVINCI+ has to analytical chemistry experiments on board
one of these. The Venus Mass Spectrometer will be able to detect phosphine throughout
the entire atmosphere, especially from the lower clouds down to the surface.
In addition, the team is considering adding a channel to the second instrument, specifically
for Phosphine. However, DAVINCI+ is a single probe. If it doesn't detect any phosphine,
that's hardly proof that there's no phosphine anywhere in the atmosphere to be found.
And that's why the probe is designed to identify several different kinds of trace gases other
than just phosphine. And that will go a long way toward determining if Venus once had or
possibly still has a habitable atmosphere. Meanwhile, the VERITAS mission will map the
surface in high resolution. VERITAS stands for Venus impulsivity, Radio science, inSAR,
Topography and Spectroscopy. It's an orbiter equipped with a synthetic aperture radar.
The radar will penetrate Venus' clouds and map the surface down to 30 meters per pixel
for really interesting surface features. The spacecraft can make additional targeted scans
that will raise the resolution up to 15 meters per pixel.
That's ten times finer than Magellan! These 3D maps will confirm whether processes such
as plate tectonics and volcanism are still active on Venus. Venus is also equipped with
the Venus Emissivity Mapper to map the surface of emissitivity in bands of the infrared parts
of the spectrum.
These bands are like windows that can see through the atmosphere and even detect the
presence of water vapor near the surface. These measurements will determine whether
active volcanoes are releasing water vapor into the atmosphere. VERITAS is expected to
map Venus over four Venusian days.
That may not seem like much, but one day on Venus lasts two hundred and twenty three days
on Earth. So we're talking about a two and a half year mapping mission. These two missions
alone will tell us a great deal about Venus and address some long standing questions,
but they'll undoubtedly raise new ones in the process.
So it's a good thing that ESA announced its EnSision mission to Venus. Like VERITAS, EnVision
is a radar mapping orbiter, but with slightly different capabilities. For example, its VenSAR
radar will get a slightly higher resolution of up to 10 meters per pixel compared to VERITAS'
15 meter resolution, but it won't be able to do targeted imaging of specific terrain
features. EnVision will begin taking data about seven years after VERITAS' arrival,
so it will be able to pick up where VERITAS left off and see if there were any short term
changes to Venus's surface.
EnVision will also carry a subsurface sounding radar that uses low frequency radio to penetrate
up to a kilometer deep into the crust. This will be used to map subsurface features and
search for any buried tectonic plate boundaries.
VenSpec is a suite of three spectrometers operating in the UV and infrared. It will
map trace gases, including those ejected by volcanoes. The Radio Science Experiment will
use radio tracking to map the planet's gravity field. That will help map out Venus's internal
structure and vision, will follow up on and complement VERITAS' global observations.
Together, they'll give us our best glimpse yet into Venus's geology and tell us how the
planet is continuing to evolve. DAVINCI+ will reveal the atmosphere of Venus to one hundred
times finer details than before and may even help us understand Venus might yet be habitable
for life in the clouds.
I wouldn't be surprised if these missions end up dispelling a number of misconceptions
about Venus that we don't yet know that we have. So, yeah, I'm really glad that NASA
and ESA are planning to go back to Venus.
But for every mission selected, others have to be passed up. In NASA's case, VERITAS and
DAVINCI+ one out over the Io Volcano Observer and the Trident mission to Neptune's moon
Triton. The last time we saw Triton up close was Voyager 2 in 1989.
Talk about unfinished business. Still, the 2030's are going to see a lot of science coming
from Venus, so I'm pretty grateful for that. And I'm also grateful for my patrons who are
helping to keep Launch Pad Astronomy going, and I'd like to welcome Josh and Robert Swayne
as my new supporters. And if you'd like to join me on this journey through this incredible
universe of ours, will please make sure you subscribe and ring that notification bell
so that you don't miss out on any new videos. Until next time, stay curious, my friends.