I think you mean on board and if that’s the case, then yes, you can replace one with the other. According to NOAD and OED, on board means:

on or in a ship, aircraft, or other vehicle. • informal onto a team or group as a member: the need to bring on board a young.

and aboard :

on or into (a ship, aircraft, train, or other vehicle): : climbing aboard the yacht.

What is to be predicted by the best science?

I think you mean on board and if that’s the case, then yes, you can replace one with the other. According to NOAD and OED, on board means:

on or in a ship, aircraft, or other vehicle. • informal onto a team or group as a member: the need to bring on board a young.

and aboard :

on or into (a ship, aircraft, train, or other vehicle): : climbing aboard the yacht.

What is to be predicted by the best science?

I think you mean on board and if that’s the case, then yes, you can replace one with the other. According to NOAD and OED, on board means:

on or in a ship, aircraft, or other vehicle. • informal onto a team or group as a member: the need to bring on board a young.

and aboard :

on or into (a ship, aircraft, train, or other vehicle): : climbing aboard the yacht.

What is to be predicted by the best science?

I think you mean on board and if that’s the case, then yes, you can replace one with the other. According to NOAD and OED, on board means:

on or in a ship, aircraft, or other vehicle. • informal onto a team or group as a member: the need to bring on board a young.

and aboard :

on or into (a ship, aircraft, train, or other vehicle): : climbing aboard the yacht.

What is to be predicted by the best science?

I think you mean on board and if that’s the case, then yes, you can replace one with the other. According to NOAD and OED, on board means:

on or in a ship, aircraft, or other vehicle. • informal onto a team or group as a member: the need to bring on board a young.

and aboard :

on or into (a ship, aircraft, train, or other vehicle): : climbing aboard the yacht.

What is to be predicted by the best science?

I think you mean on board and if that’s the case, then yes, you can replace one with the other. According to NOAD and OED, on board means:

on or in a ship, aircraft, or other vehicle. • informal onto a team or group as a member: the need to bring on board a young.

and aboard :

on or into (a ship, aircraft, train, or other vehicle): : climbing aboard the yacht.

What is to be predicted by the best science?

I think you mean on board and if that’s the case, then yes, you can replace one with the other. According to NOAD and OED, on board means:

on or in a ship, aircraft, or other vehicle. • informal onto a team or group as a member: the need to bring on board a young.

and aboard :

on or into (a ship, aircraft, train, or other vehicle): : climbing aboard the yacht.

What is to be predicted by the best science?

I think you mean on board and if that’s the case, then yes, you can replace one with the other. According to NOAD and OED, on board means:

on or in a ship, aircraft, or other vehicle. • informal onto a team or group as a member: the need to bring on board a young.

and aboard :

on or into (a ship, aircraft, train, or other vehicle): : climbing aboard the yacht.

What is to be predicted by the best science?

I think you mean on board and if that’s the case, then yes, you can replace one with the other. According to NOAD and OED, on board means:

on or in a ship, aircraft, or other vehicle. • informal onto a team or group as a member: the need to bring on board a young.

and aboard :

on or into (a ship, aircraft, train, or other vehicle): : climbing aboard the yacht.

What is to be predicted by the best science?

I think you mean on board and if that’s the case, then yes, you can replace one with the other. According to NOAD and OED, on board means:

on or in a ship, aircraft, or other vehicle. • informal onto a team or group as a member: the need to bring on board a young.

and aboard :

on or into (a ship, aircraft, train, or other vehicle): : climbing aboard the yacht.

What is to be predicted by the best science?