COSMIC SWEET SPOTS

TOPIC: Science & Tech

Context- It is easier and cheaper to launch rockets from cosmic sweet spots.

Concept-

A sweet Spot is an optimum point or combination of factors or qualities.
There are two such sweet spots — the second was discovered only recently.
They are ‘Trojan asteroids’.
- These kinds of asteroids travel alongside a planet in its journey around the sun. A fellow-traveller, a hamsafar!
The second Earth Trojan asteroid, named 2020XL5, was discovered in late 2020, but conﬁrmed only recently.
- 2020XL5 is about 1.2 km across — thrice as big as the ﬁrst Earth Trojan asteroid, named 2010TK7.
Both the Earth Trojan asteroids sit at the Lagrange point 4 (L-4), which is one of the ﬁve spots of equilibrium between the Earth and the sun
- a Lagrange point between two bodies is where an object remains stable, and won’t drift away, because it is pulled with equal force by the two bodies.

Asteroids:

An asteroid is a minor planet of the inner Solar System.
Asteroids are diﬃcult to ﬁnd because they are small and typically don’t reﬂect much light (low albedo).
Larger asteroids are often called planetoids.
Asteroids are somewhat arbitrarily differentiated from comets and meteoroids.
- In the case of comets, the difference is one of composition: while asteroids are mainly composed of mineral and rock, comets are primarily composed of dust and ice. Furthermore, asteroids formed closer to the sun.
- The difference between asteroids and meteoroids is mainly one of size: meteoroids have a diameter of one meter or less, whereas asteroids have a diameter of greater than one meter.