Comets (II)

Interesting stuff to learn or merely a temporary dirt cloud ?

This is part second of “Comets”. Here, we will discuss technical part in the case of asteroid. Click here to see the first part

To find the type of its orbit, we need to know the value of eccentricity. There are many ways to find it. But, as per the information I have, the following formula will be the easiest.


= perihelion= 10.95 AU

= Semi-major axis(here, orbital radius=R) =

= Eccentricity.



= 54,000 AU (outbound)

Now, we need to find the semi-major

We know that,

After putting the values and solving further,


Now, put all the values in the following equation and solve


The resultant values might change in future due to some inevitable circumstances. However, for the current interval its eccentricity(e) is 0.99960 and the semi-major axis is 27000 AU. By the value of eccentricity, we can conclude that Comet Bernardinelli-Bernstein has an Elliptical orbit . It is much farther away. The value- 27000 AU- shows that this object is a part of the Oort cloud.

Similarly, by applying some mathematics we can get the value of the inclination(i) of the orbit of this comet. We can get orbital inclination(i)= 95.568°. So, if you want to trace the path of this comet in the sky you need to do a few steps.Take a celestial map, mark the ecliptic (p-1)on it, mark another path (p-2) just 95.568 degrees from the ecliptic, finally look through p-2 in the sky and you will see the comet. The same method can be applied in case of other celestial bodies after manipulating the values. Then, be ready to verify this method in the year 2031.

But, what if you missed it due some inexorable circumstances? If astronomy is the universe, then maths is the language of it. Let’s find out when the comet will return.

To find the time of its return, we first have to find the time period (in years) of the comet by using available data. Then we will add it to the current year. This method is similar for any celestial body that has a closed orbit- elliptical or circular.

So, let us bring the following formula into the picture.


= Time period of the comet

= Orbital radius= 27000 AU

= Universal gravitation constant=

= Mass of the Sun=


= Mass of Comet Bernardinelli-Bernstein


But, the period- 4.5 million is longer than expected. We can see the next approach of this comet in the year- 4502021. Maybe, humanity will have settled in another solar system by this time. So, the best we can do is to grab the opportunity.

I am a high school student and an excellent astrophysics enthusiast