Calling science a religion should be instantly recognized as an ideological attack rather than a neutral observation of facts. Sadly this is not the case, and it has become far too common for critics of modern, godless science to claim that its inherently a religion, thus hoping to discredit scientific research when it contradicts genuine religious ideology. Examining the characteristics which define religions as distinct from other types of belief systems reveals how wrong such claims are.
The most common and fundamental characteristic of religion is belief in supernatural beings usually, but not always, including gods. Few religions lack this characteristic and most religions are founded upon it. Does science involve belief in supernatural beings like gods? No many scientists are themselves theists and/or religious in various ways while many others are not. Science itself as a discipline and profession is godless and secular, promoting no religious or theistic beliefs.
Differentiating between sacred and profane objects, places, and times helps religious believers focus on transcendental values and/or the existence of a supernatural realm. Many scientists, godless or not, probably have things, places, or times which they consider sacred in the sense that they are venerated in some way. Does science itself involve such a distinction? No it neither encourages nor discourages it. Some scientists may believe that some things are sacred, and others wont.
If people believe in something sacred, they probably have rituals associated with it which are also sacred. A scientist who holds something as sacred may engage in some sort of ritual or ceremony. As with the very existence of a category of sacred things, however, there is nothing about science which either mandates such a belief or excludes it. Some scientist participate in rituals and some dont; there are no scientific rituals, godless or otherwise.
Most religions preach a moral code which is typically based upon whatever transcendental and supernatural beliefs are fundamental to that religion. Thus, for example, theistic religions typically claim that morality is derived from the commands of their gods. Scientists have personal moral codes which they may believe have supernatural origins, but those are not an inherent part of science. Scientists also have professional codes which have purely human origins.
Perhaps the vaguest characteristic of religion is the experience of religious feelings like awe, a sense of mystery, adoration, and even guilt. Religions encourage such feelings, especially in the presence of sacred objects and places, and the feelings are typically connected to the presence of the supernatural. Most scientists experience such feelings; often, its a reason why they got involved in science. Unlike religions, however, these feelings have nothing to do with the supernatural.
Belief in supernatural beings like gods doesnt get you very far if you cant communicate with them, so religions which include such beliefs naturally also teach how to talk to them usually with some form of prayer or other ritual. Most scientists believe in a god and therefore probably pray; other scientists dont. Because there is nothing about science which encourages or discourages belief in the supernatural, there is also nothing about it which deals with prayer.
Religions constitute entire worldviews and teach people how to structure their lives in relation to their worldview: how to relate to others, what to expect from social relationships, how to behave, etc. Scientists have worldviews, and there are common beliefs among scientists in America, but science itself doesnt quite amount to a worldview. It provides a basis to a scientific worldview, but different scientists will arrive at different conclusions and incorporate different elements.
A few religious people follow their religions in isolated ways; more often than not religions involve complex social organizations of believers who join each other for worship, rituals, prayer, etc. Scientists belong to a variety of groups, many of which will be scientific in nature, but not all the same groups. Whats important, though, is the fact that even these scientific groups are not bound together by all of the above. There is nothing in science which is even remotely like a church.
Modern science is necessarily godless because godlessness provides science with the independence of religious ideologies which is necessary to ruthlessly pursue the facts wherever they may lead. Modern science is successful precisely because it strives to be independent of ideology and bias, even if only imperfectly. Unfortunately, this independence is also the primary reason for attacks on it. When it comes to people who insist that their religious and theistic beliefs be incorporated into every aspect of their lives, the absence of those beliefs in others lives becomes almost incomprehensible.
In the case of science, it isnt just a few lives which are godless, but an entire field of study which is obviously fundamental to the modern world. Its difficult for some people to reconcile their own dependence on the fruits of modern science with the fact that science is methodologically naturalistic, secular, and godless. Because of this, some people deny that science needs to be godless and insist that their personal religious or theistic beliefs start to be incorporated into the scientific process. That they would effectively kill the means by which science is successful either isnt recognized or doesnt matter its their ideology which matters and of course serving the goal of spreading that ideology far and wide.
It is for this reason that attempts to label godless science as a religion must not only be resisted, but outright rejected. The hope is that if people perceive science as just another religion, then sciences ideological independence will become forgotten, thus making it easier to incorporate real religion into it. Its strange that devout religious followers would employ the religion label as an attack, but this merely demonstrates their lack of principle and why they cannot be trusted. Science doesnt fit any scholarly definition of religion; portraying it as a religion does, however, fit the ideological goals of anti-modern ideologues.

