To get a B.Tech in Nautical Science, you would need to look at colleges in other parts of India. Some of the prominent maritime training institutes and universities offering B.Sc. (Nautical Science) programs (which can be a pathway to a career as a navigating officer) include:

* Indian Maritime University (IMU) - They have campuses in Chennai, Kochi, Kolkata, Mumbai Port, and Navi Mumbai.

* Tolani Maritime Institute (TMI) - Located in Pune and Mumbai.

* Maharashtra Academy of Naval Education and Training (MANET) - Located in Pune.

* Hindustan Institute of Maritime Training (HIMT) - Located in Chennai.

* Academy of Maritime Education and Training (AMET) University - Located in Chennai.

* GKM Institute of Marine Sciences and Technology - Located in Chennai.

* Samundra Institute of Maritime Studies (SIMS) - Located in Lonavala (near Mumbai).

* BP Marine Academy - Located in Navi Mumbai.

It's important to note the following:

* B.Sc. vs. B.Tech: Many top institutes in India offer a Bachelor of Science (B.Sc.) in Nautical Science rather than a B.Tech. This degree is specifically designed to train individuals to become navigating officers in the merchant navy.

* Eligibility: Generally, for these programs, you need to have passed your 10+2 (or equivalent) with Physics, Chemistry, and Mathematics (PCM) as subjects and a certain minimum percentage of marks. English language proficiency is also usually required.

* Entrance Exams: Some institutes have their own entrance exams, while others may accept the Indian Maritime University Common Entrance Test (IMU CET).

* Medical Fitness: Aspiring seafarers need to meet specific medical standards.

Recommendations for you:

* Consider B.Sc. Nautical Science: If your goal is to work as a navigating officer on ships, a B.Sc. in Nautical Science is a widely recognized and suitable degree.

* Research Colleges Outside Aligarh: Explore the colleges listed above in other maritime hubs of India like Chennai, Mumbai, Pune, and Kochi.

* Check Specific College Websites: Visit the websites of the colleges you are interested in to get detailed information about their programs, eligibility criteria, admission procedures, fees, and placement records.

* Contact the Colleges: If you have specific questions, don't hesitate to reach out to the admissions offices of these colleges.

While you might need to relocate from Aligarh to pursue your desired degree, there are many reputable institutions in India offering excellent programs in nautical science and marine engineering.