Read the Beforeitsnews.com story here. Advertise at Before It's News here.

By Now Appearing
Contributor profile | More stories

Story Views
Now:
Last hour:
Last 24 hours:
Total:

Is the Earth gaining a second moon?

Monday, September 30, 2024 5:26

% of readers think this story is Fact. Add your two cents.

By Brian Clegg

I was amused to read on the BBC News site ‘ Get ready for a cosmic surprise this autumn – Earth is about to get a second moon, according to scientists.’ I named my first science quiz book How Many Moons does the Earth Have? precisely because of this kind of silliness. My answer was ‘one’ and it still will be while a chunk of passing rock is briefly caught by Earth’s gravitational pull.

Apart from anything, the suggestion that something is a moon just because it is briefly pulled off track by a planet’s gravity seems to reflect an underlying misunderstanding of how gravity works. Everything with mass distorts spacetime and causes moving objects to be displaced from their natural straight line path. This would make practically everything in space a moon if you took this argument to its limit, because they are all being pulled of track by the planets.

The news item is also amusing because back in 2013, the TV show QI claimed that the Earth had a large number of moons (it was QI’s various attempts at numbering our moons at more than one that inspired my book in the first place). If this were true, the current story isn’t even news. But it’s not really: I reproduce below what I wrote at the time.

QI excuse their latest, 20,000 (that’s from memory – it was some large number) value [for the number of the Earth’s moons] by saying there are lots of little lumps of rock that get captured by Earth’s gravitational field for a few days and while captured they are natural satellites, which makes them moons. But this is the excrement of the male cow. You might as well say the Sun has many thousands of planets, because of all the asteroids, as a planet is a satellite of the Sun. However, we all know there are just eight planets.

Now to be fair, with planets there are clearer rules. To be a planet the body has to (in my wording):

Orbit the Sun
Be roughly spherical
Have swept its orbit clean of minor debris

… this last one being the rule that did for Pluto. But I would suggest, whether or not there is an IAU definition of ‘moon’ as there is for ‘planet’ there are still clear intended consequences of using the word ‘moon’ as opposed to just ‘satellite’. These are that the body in question should be:

Long lasting – I suggest staying in orbit for at least 1,000 years
Sizeable – say at least 5 kilometres across

This would still allow moon status for the pretty dubious companions of Mars, Phobos and Deimos, which are about 20 kilometres and 10 kilometres across. For comparison, the ‘moon’ described by BBC News is 10 metres across.

Clearly such rules are there implicitly when we talk about moons. If the time rule didn’t exist, then every lump of rock that spent 5 minutes in our company would be a moon, while without the size rule, we would have to count every tiny piece of debris in Saturn’s rings as a moon – every one of them is, after all, a natural satellite.

Image (which really is a moon) from Wikipedia by Gregory H. Rivera reproduced under CC3.0

These articles will always be free – but if you’d like to support my online work, consider buying a virtual coffee:

See all Brian's online articles or subscribe to a weekly email free here

Now Appearing is the blog of science writer Brian Clegg (www.brianclegg.net), author of Inflight Science, Before the Big Bang and The God Effect.

Source: http://brianclegg.blogspot.com/2024/09/is-earth-gaining-second-moon.html

Before It’s News® is a community of individuals who report on what’s going on around them, from all around the world.

Anyone can join.
Anyone can contribute.
Anyone can become informed about their world.

"United We Stand" Click Here To Create Your Personal Citizen Journalist Account Today, Be Sure To Invite Your Friends.

Before It’s News® is a community of individuals who report on what’s going on around them, from all around the world. Anyone can join. Anyone can contribute. Anyone can become informed about their world. "United We Stand" Click Here To Create Your Personal Citizen Journalist Account Today, Be Sure To Invite Your Friends.

LION'S MANE PRODUCT

Try Our Lion’s Mane WHOLE MIND Nootropic Blend 60 Capsules

Mushrooms are having a moment. One fabulous fungus in particular, lion’s mane, may help improve memory, depression and anxiety symptoms. They are also an excellent source of nutrients that show promise as a therapy for dementia, and other neurodegenerative diseases. If you’re living with anxiety or depression, you may be curious about all the therapy options out there — including the natural ones.Our Lion’s Mane WHOLE MIND Nootropic Blend has been formulated to utilize the potency of Lion’s mane but also include the benefits of four other Highly Beneficial Mushrooms. Synergistically, they work together to Build your health through improving cognitive function and immunity regardless of your age. Our Nootropic not only improves your Cognitive Function and Activates your Immune System, but it benefits growth of Essential Gut Flora, further enhancing your Vitality.

Our Formula includes: Lion’s Mane Mushrooms which Increase Brain Power through nerve growth, lessen anxiety, reduce depression, and improve concentration. Its an excellent adaptogen, promotes sleep and improves immunity. Shiitake Mushrooms which Fight cancer cells and infectious disease, boost the immune system, promotes brain function, and serves as a source of B vitamins. Maitake Mushrooms which regulate blood sugar levels of diabetics, reduce hypertension and boosts the immune system. Reishi Mushrooms which Fight inflammation, liver disease, fatigue, tumor growth and cancer. They Improve skin disorders and soothes digestive problems, stomach ulcers and leaky gut syndrome. Chaga Mushrooms which have anti-aging effects, boost immune function, improve stamina and athletic performance, even act as a natural aphrodisiac, fighting diabetes and improving liver function. Try Our Lion’s Mane WHOLE MIND Nootropic Blend 60 Capsules Today. Be 100% Satisfied or Receive a Full Money Back Guarantee. Order Yours Today by Following This Link.

Comments

Online:
Visits:	1,645,836,581
Stories:	8,265,948