The first law of physics is that an object will remain at rest or in a uniform state of motion unless that state is changed by an external force. To a great degree, that same principle applies to momentum in the stock market. Momentum will continue until some outside force in the form of news or emotions exerts force on the price action.

Some folks may scoff at the application of physics to the stock market, but the principle is fundamental to most everything in the world. Behavior and movement doesn't change unless there is some outside force of sufficient magnitude to change it.

I've often written a simplistic variation of this idea, which is that trends tend to last longer and go further than most people think is reasonable. Trying to apply "reasonableness" to the stock market doesn't work well, because it is not a sufficient outside force to kill momentum.

When we contemplate the current market action, what is a force that may eventually come into play and change the market direction?

The most obvious answer is an actual "phase one" trade deal between Washington and Beijing. The market has gained momentum in continuous headlines and stories about how a trade deal is progressing and will eventually be accomplished. Those stores keep the momentum going and there is no other force to stop it.

Once an actual trade deal is completed that catalyst will disappear. Eventually, there will be talk about a "phase 2" deal to serve the same purpose, but that time frame is long enough that it won't have an immediate impact.

An actual trade deal now would be such an obvious "sell the news" event that we have to wonder if it will work. We won't know until the news finally occurs how it will play out, but it is the outside force that can change the trajectory of the market action.

As I write, the indexes continue to sail along to the upside and hit new highs. Breadth is running 4,200 gainers to 3,100 decliners, and there are around 600 new 12-month highs. The first law of physics appears to be working well for the bulls, but at some point that outside force will hit and that will require us to react.

Astronomers with the Chinese Academy of Sciences have announced the discovery of a black hole within our galaxy that they claim has a mass 70 times greater than our Sun. The startling discovery dashes what was previously believed to be the upper limit for a black hole’s mass — one typically thought to top out at around 20 times the mass of our Sun.

The study detailing the findings was recently published in the prominent scientific journal Nature, where the researchers describe their massive discovery. The black hole has been named LB-1 and is located around 15,000 light-years from Earth. The discovery was made possible using a popular technique that involves looking for stars orbiting an object that is invisible.

The majority of known black holes were discovered by detecting the x-ray emissions produced when they destroy a nearby star. This process quite obviously has one big limitation: the discovery of the black hole is dependent upon whether it is caught shredding a companion star. This is a relatively uncommon activity, meaning most black holes have gone undetected.

Surveying the sky using modern technology has proven common and useful for detecting black holes over the last few years. In the case of this latest study, the researchers used the Large Sky Area Multi-Object Fiber Spectroscopic Telescope that belongs to China. Once an unusual star orbit was detected, the team used two of the biggest telescopes in the world — one located in Spain and the other in the US — to assess the properties of the invisible object.

The scientists concluded that the detected system features a black hole with a mass 70 times our Sun that is being orbited by a star that is eight times heavier than our star. This orbit takes 79 days to complete. National Astronomical Observatory of China Professor LIU Jifeng who lead the research team said of the discovery:

Black holes of such mass should not even exist in our Galaxy, according to most of the current models of stellar evolution … they should not leave behind such a massive remnant. LB-1 is twice as massive as what we thought possible.