The First Space Launch System Hardware From NASA’s Michoud Assembly Facility In New Orleans Just Arrived

NASA’s Cassini spacecraft is set to make its first dive through the narrow gap between Saturn and its rings on April 26, 2017. Because that gap is a region no spacecraft has ever explored, Cassini will use its dish-shaped high-gain antenna (13 feet or 4 meters across) as a protective shield while passing through the ring plane. No particles larger than smoke particles are expected, but the precautionary measure is being taken on the first dive. The Cassini team will use data collected by one of the spacecraft’s science instruments (the Radio and Plasma Wave Subsystem, or RPWS) to ascertain the size and density of ring particles in the gap in advance of future dives. As a result of its antenna-forward orientation, the spacecraft will be out of contact with Earth during the dive.

Below is a list of milestones expected to occur during the event, if all goes as planned:

– 5 p.m. PDT (8 p.m. EDT) on April 25: Cassini is approaching Saturn over the planet’s northern hemisphere in advance of its first of 22 planned dives through the gap between the planet and its rings.

– 1:34 a.m. PDT (4:34 a.m. EDT) on April 26: As it passes from north to south over Saturn, Cassini begins a 14-minute turn to point its high-gain antenna into the direction of oncoming ring particles. In this orientation, the antenna acts as a protective shield for Cassini’s instruments and engineering systems.

– 2 a.m. PDT (5 a.m. EDT) on April 26: Cassini crosses the ring plane during its dive between the rings and Saturn. The spacecraft’s science instruments are collecting data, but Cassini is not in contact with Earth at this time.

– No earlier than around midnight PDT on April 26 (3 a.m. EDT on April 27): Earth has its first opportunity to regain contact with Cassini as the giant, 230-foot (70-meter) Deep Space Network antenna at Goldstone, California, listens for the spacecraft’s radio signal.

∞ x ∞ = ∞

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Explain this to me...

“Quantum cryptography uses the quantum properties of photons to guarantee perfect secrecy. But one of its lesser known limitations is that it only works if Alice and Bob are perfectly aligned so that they can carry out well-defined polarization measurements on the photons as they arrive. Physicists say that Alice and Bob must share the same reference frame. That’s OK if Alice and Bob are in their own ground-based labs, but it’s a problem in many other applications, such as ground-to-satellite communications or even in chip-to-chip communications, because it’s hard to keep chips still over distances of the order of the wavelength of light. Now a group of UK physicists have developed a way of doing quantum cryptography without sharing a reference frame. The trick is to use entangled triplets of photons, so-called qutrits, rather than entangled pairs. This solves the problem by embedding it in an extra abstract dimension, which is independent of space. So, as long as both Alice and Bob know the way in which all these abstract dimensions are related, the third provides a reference against which measurements of the other two can be made. That allows Alice and Bob to make any measurements they need without having to agree ahead of time on a frame of reference. That could be an important advance enabling the widespread use of quantum cryptography.”

This view of Jupiter shows the giant planet’s cloud tops taken by the Pioneer 10 spacecraft as it flew past Jupiter. This view was taken from 2,695,000 kilometers (1,842,451 miles) away. It shows the 25,000 mile long Great Red Spot, which is large enough to swallow up several Earths. Individual cloud formations are visible in some detail. The bright zones appear to become split up into the detailed flow patterns of Jupiter’s atmosphere and clouds. The area surrounding the Spot in the bright South Tropical Zone, suggests a flow pattern about the Spot which is bulged toward the north by the Spot. The Spot may be a gigantic “permanent hurricane.” The gigantic cloud swirls are thousands or more miles across. Pioneer 10 flew past Jupiter in December 1974 and flew past the orbit of Pluto in 1987. A sister spacecraft, Pioneer 11 reached Jupiter in December 1975. The Pioneer Project was managed by NASA’s Ames Research Center, Mountain View, Calafornia. The spacecraft was built by TRW Systems.

don’t assume the gender of my HYDROGEN! ok

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Comet Lovejoy C/2013 R1. Taken by Gerald Rhemann, December 2013.

Jupiter’s Great Red Spot is such a crazy, turbulent storm (the largest known storm in the universe) that it creates sound waves that travel hundreds of miles up and actually heat the planet’s upper atmosphere.

I repeat: sound waves are heating Jupiter’s atmosphere. The area above the Spot is a thousand degrees Fahrenheit hotter than the surrounding atmosphere.

Here’s the journal paper. Here’s our story.

Image credit: Space Telescope Science Institute/NASA