# Tag Info

15

It probably is a dwarf planet. (It almost certainly is a dwarf planet.) The naming procedures at the IAU are that "Objects that have an absolute magnitude (H) less than +1 [...] are overseen by two naming committees, one for minor planets and one for planets. [...] All other bodies are named by the minor-planet naming committee alone." source—wikipedia ...

8

That actual IAU Resolution B5 adopted at the IAU General Assembly in 2006 states: (1) A planet is a celestial body that: (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (c) has cleared the neighbourhood around its orbit. The ...

5

Dawn was not exploring L3. But instead it explored both Vesta and Ceres. In order to do so in a cost-saving manner, Dawn was also a mission demonstrator for an interplanetary mission equipped with ion propulsion. Because of the low specific impulse of ion propulsion, Dawn cannot fly in a straight line, as this would imply a high initial velocity and the ...

3

Celestia can run on MacOS. With is, you can travel in the solar system and in time. It can give you a good idea of how far things are from each other.

3

Even rocky planets would explode. I think there are two ways to see this. From the perspective of forces, the earth is in equilibrium between the compressive force of gravity and the elastic resistance to compression of the materials that make it up. By Newton's third law, the mantle is pressing upwards on the crust with a force equal to the weight of the ...

2

i guess if there were no gravity then the planets would not have been formed in the very first step because they are formed, as are stars and all other celestial objects, after the collision of particles which formed clusters, which then acquired sufficient gravity to pull more mass.

2

The hydrostatic equilibrium only dictates that the object holds a spherical shape, it does not determine whether the matter will in a solid form. Gravity acts on planets, dwarf planets, comets, minor planets, and asteroids to keep them as a coherent form. Gravity acts on all matter in the universe. On smaller scales, human scale and smaller, other ...

2

No, rocky planets would not explode. However, without gravity there would be no force to make the object round though. Atmospheres would escape to space though. Since air pressure is quite nice gradient from vacuum to normal air pressure, I would assume no major explosion would occur if gravity suddenly vanished. Gas planets however would indeed explode ...

2

The Earth orbits the Sun in a counter-clockwise direction. Covering $2 \pi \times 150\times 10^6$ million kilometers in $365.25 \times 24 \times 3600$ seconds, or 29.9 km/sec. If you wanted to leave the Earth in a clockwise heliocentric orbit you'd have to accelerate Dawn by an extra 60 km/sec to do that, which is unfeasible with current rockets. Likewise ...

2

Intention to answer "Is there still a possibility that Makemake is not ellipsoidal but asteroid-shaped?" Probably not under reasonable assumptions. From Ortiz et. al. (2012) "Albedo and atmospheric constraints of dwarf planet Makemake from a stellar occultation" https://www.nature.com/articles/nature11597 Our preferred solution that ...

1

If you specificaly want to know the distance between planetary bodies, you can use the astronomical calculations tool in Stellarium. To access the tool, either press F10, or go to the left hand side toolbar pictured below From there, go to the "PC" (for "Planetary Calculations") page Here, you can select any two bodies in the Solar System (including the ...

1

You can use stellarium. It allows to stimulate view for any time. And it allows to set your observation points onto any place on many different solar system bodies. Then you can see the distance to another body. You can import your own bodies, and this get distances to those from existing bodies, and very likely even set them as observation origin. I ...

1

While, as far as we know, this is impossible, it is interesting to consider what would happen. Most likely the planet would break apart and possibly, depending on several factors, explode. Rotation speed of the planet, strength of the planet, and presence of liquids or gasses on the planet would all come into play. Here is how I would imagine it playing ...

Only top voted, non community-wiki answers of a minimum length are eligible