很久以前，在一个不再存在的星云中，我们新生的行星受到了巨大的撞击，如此精力充沛，它融化了行星的一部分和撞击器，并形成了一个旋转的熔化的水珠。热熔岩石的旋转盘转得如此之快，以至于很难分辨出行星与磁盘之间的区别。这个对象被称为“synestia”，并且理解它的形成可能会对行星形成过程产生新的见解。行星诞生的synestia阶段听起来像奇怪的科幻电影，但它可能是世界形成的自然步骤。在太阳系的大部分行星的诞生过程中很可能发生过几次，特别是水星，金星，地球和火星的岩石世界。这是一个名为“吸积”的过程的一部分，在这个过程中，一个称为原行星盘的星球上的小块岩石撞在一起，形成更大的物体，称为星子。星子撞在一起制造行星。这些影响会释放出巨大的能量，从而转化为足够的热量来融化岩石。随着世界变得越来越大，它们的引力有助于将它们结合在一起并最终起到“四舍五入”形状的作用。较小的世界（如卫星）也可以形成相同的方式。
澳洲昆士兰理工大学Essay代写：作为一个地球形式会发生什么？
A long time ago, in a nebula that no longer exists, our newborn planet was hit with a giant impact so energetic that it melted part of the planet and the impactor and created a spinning molten glob. That whirling disk of hot melted rock was turning so fast that from the outside it would have been difficult to tell the difference between the planet and the disk. This object is called a “synestia” and understanding how it formed may lead to new insights into the process of planetary formation. The synestia phase of a planet’s birth sounds like something out of weird science fiction movie, but it may be a natural step in the formation of worlds. It very likely happened several times during the birth process for most of the planets in our solar system, particularly the rocky worlds of Mercury, Venus, Earth, and Mars. It’s all part of a process called “accretion”, where smaller chunks of rock in a planetary birth créche called a protoplanetary disk slammed together to make bigger objects called planetesimals. The planetesimals crashed together to make planets. The impacts release huge amounts of energy, which translates into enough heat to melt rocks. As the worlds got larger, their gravity helped hold them together and eventually played a role in “rounding” their shapes. Smaller worlds (such as moons) can also form the same way.