Cosmology & Astronomy on Khan Academy: The Earth is huge, but it is tiny compared to the Sun (which is super huge). But the Sun is tiny compared to the solar system which is tiny compared to the distance to the next star. Oh, did we mention that there are over 100 billion stars in our galaxy (which is about 100,000 light years in diameter) which is one of hundreds of billions of galaxies in just the observable universe (which might be infinite for all we know). Don’t feel small. We find it liberating. Your everyday human stresses are nothing compared to this enormity that we are a part of. Enjoy the fact that we get to be part of this vastness!

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Flight test of a quaternion based attitude controller with adaptive augmentation. The associated paper has been presented under the title “High Performance Adaptive Attitude Control of a Quadrotor” at the European Control Conference (ECC) 2019 in Naples, Italy. Work done at the Control Methods and Robotics Lab at Technische Universität Darmstadt, Germany by: Dinu Mihailescu-Stoica…

Calculus: We compute the antiderivative of x^2/(4x^2-36)^2 using partial fractions. In this case, the denominator factors into repeated linear factors.

Need help with SAT writing? Join Eric, one of Khan Academy’s SAT experts, for a live SAT writing class Tuesday, May 30 at 7 pm ET/4pm PT. It’s free! Eric will walk through key grammar concepts like subject-verb agreement and sentence punctuation. Can’t make it? We’ll record the class and post the link in this…