By NASA’s Juno Spacecraft.

Jupiter’s Racing Stripes by NASA’s Marshall Space Flight Center

what is your favorite natural satellite?

Saturn Aurora.

Credit: NASA, ESA, J Clarke and Z Levay

In Cassini’s final days, it is sweeping through dramatic, close flybys of Saturn’s rings

(Image credit: NASA/JPL-Caltech/Space Science Institute)

Space Shuttle launch. 🌎🚀

Mars Helicopter: 6 Things to Know About Ingenuity

When our Perseverance Mars rover lands on the Red Planet on Feb. 18, 2021, it will bring along the Ingenuity helicopter.

This small-but-mighty craft is a technology demonstration that will attempt the first powered, controlled flight on another planet. Its fuselage is about the size of a tissue box, and it weighs about 4 pounds (1.8 kg) on Earth. It started out six years ago as an implausible prospect and has now passed its Earthbound tests.

Here are six things to know about Ingenuity as it nears Mars:

1. Ingenuity is an experimental flight test.

This Mars helicopter is known as a technology demonstration, which is a project that aims to test a new capability for the first time with a limited scope. Previous technology demonstrations include Sojourner, the first Mars rover, and the Mars Cube One (MarCO) CubeStats that flew by Mars.

Ingenuity does not carry any science instruments and is not part of Perseverance’s science mission. The only objective for this helicopter is an engineering one – to demonstrate rotorcraft flight in the thin and challenging Martian atmosphere.

2. Mars won’t make it easy for Ingenuity.

Mars’ atmosphere is around 1% the density of Earth’s. Because of that lack of density, Ingenuity has rotor blades that are much larger and spin faster than a helicopter of Ingenuity’s mass here on our planet. It also must be extremely light to travel to Mars.

The Red Planet also has incredibly cold temperatures, with nights reaching minus 130 degrees Fahrenheit (-90 degrees Celsius) in Jezero Crater, where our rover and helicopter will land. Tests on Earth at the predicted temperatures indicate Ingenuity’s parts should work as designed, but the real test will be on Mars.

3. Ingenuity relies on Perseverance for safe passage to Mars and operations on the Martian surface.

Ingenuity is nestled sideways under Perseverance’s belly with a cover to protect the helicopter from debris during landing. The power system on the Mars 2020 spacecraft periodically charges Ingenuity’s batteries during the journey to the Red Planet.

In the first few months after landing, Perseverance will find a safe place for Ingenuity. Our rover will shed the landing cover, rotate the helicopter so its legs face the ground and gently drop it on the Martian surface.

4. Ingenuity is smart for a small robot.

NASA’s Jet Propulsion Laboratory will not be able to control the helicopter with a joystick due to delays communicating with spacecraft across interplanetary distances. That means Ingenuity will make some of its own decisions based on parameters set by its engineering team on Earth.

During flight, Ingenuity will analyze sensor data and images of the terrain to ensure it stays on a flight path designed by project engineers.

5. The Ingenuity team counts success one step at a time.

Ingenuity’s team has a long list of milestones the helicopter must pass before it can take off and land in the Martian atmosphere.

Surviving the journey to and landing on Mars

Safely deploying onto the Martian surface from Perseverance’s belly

Autonomously keeping warm through those intensely cold Martian nights

Autonomously charging itself with its solar panel

Successfully communicating to and from the helicopter via the Mars Helicopter Base Station on Perseverance

6. If Ingenuity succeeds, future Mars exploration could include an ambitious aerial dimension.

The Mars helicopter intends to demonstrate technologies and first-of-its-kind operations needed for flying on Mars. If successful, these technologies and flight experience on another planet could pave the way for other advanced robotic flying vehicles.

Possible uses of a future helicopter on Mars include:

A unique viewpoint not provided by current orbiters, rovers or landers

High-definition images and reconnaissance for robots or humans

Access to terrain that is difficult for rovers to reach

Could even carry light but vital payloads from one site to another

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Perseverance: Some early Navcam (navigation camera) images taken over the (Earth) weekend on sol 2. Originals are here: [1] [2] [3] [4]. Credit: NASA/JPL-Caltech

What Separates A Good Scientific Theory From A Bad One?

“It’s why an idea like dark matter is so powerful. By adding just a single new species of particle — something that’s cold, collisionless, and transparent to light and normal matter — you can explain everything from rotating galaxies to the cosmic web, the fluctuations in the microwave background, galaxy correlations, colliding galaxy clusters, and much, much more. It’s why ideas with a huge number of free parameters that must be tuned to get the right results are less satisfying and less predictively powerful. If we can model dark energy, for instance, with just one constant, why would we invent multi-field models with many parameters that are no more successful?”

You’ve often heard, when discussing competing scientific ideas, of appealing to Occam’s razor. Often paraphrased as “all things being equal, the simplest explanation is usually best,” it seems to open the door for people to argue over which explanation is simplest. This should not, however, be a point of contention: the explanation that’s simplest is the one that introduces the fewest number of new, additional free parameters. And when it comes to all things being equal, the things in question ought to be the number of new phenomena the novel idea can explain, along with the number of discernible predictions as compared with the old, prevailing idea. The best scientific ideas are the ones that explain the most by adding the least, while the worst ones unnecessarily add additional parameters on top of what we observe for no good reason other than personal bias. Ideas may be a dime-a-dozen, but a good idea is hard to find.

The next time you encounter an interesting, wild idea that someone throws out there, use this criteria to evaluate it. You just might be surprised at how quickly you can tell whether an idea is good or bad!