Doppler effect

• The gallium nitride segment is projected to grow at the highest CAGR rate for the military transmit and receive module market during the forecast period.
• By platform, the airborne segment is estimated to account for the largest market share of the Military transmit and receive module market in 2023.
• The airborne segment is estimated to account for the largest share of 42% of the military transmit and receive module market in 2023.
• The North American market is going to contribute the largest share of 36% to the military transmit and receive module industry in 2023.

• The marine control systems market is driven by vessel modernization efforts; the need for enhanced efficiency and safety propels the adoption of various control systems for propulsion, navigation, and automation.
• The Marine Onboard Communication and Control Systems market encompasses a type, platform, and end-user that leverages these benefits.
• Based on the type, the control systems segment is estimated to lead the Marine Onboard Communication and Control Systems industry from 2023 to 2028.
• To meet the regulatory compliance the navies are adopting various propulsion control systems, engine control and monitoring systems which drive the marine control systems market.

• PALO ALTO, Calif., Nov. 29, 2023 /PRNewswire/ -- Baraja , creator of the breakthrough Spectrum-Scan™ LiDAR technology, announces the availability of A-Samples of all the integrated components necessary to build a new-to-world Doppler RMCW Spectrum-Scan™ LiDAR for automotive integration.
• "Multiple heterogeneous sub-systems are contained in a LiDAR, this would require each sub-system's integration via completely different classes of chips and using different processes.
• The Bidirectional Optical Sub-Assembly (BOSA) integrates 3 types of chips in an automotive-grade, hermetically sealed and temperature controlled enclosure (3x3.5cm).
• These chips are: the laser chip (InP), the homodyne receiver chip (silicon photonics) and the TIA chips (silicon).

• Why is space so dark despite all of the stars in the universe?
• – Nikhil, age 15, New Delhi
  Why is space so dark despite all of the stars in the universe?
• – Nikhil, age 15, New Delhi People have been asking why space is dark despite being filled with stars for so long that this question has a special name – Olbers’ paradox.
• The study of distant stars and planets helps astronomers like me understand why space is so dark.

Imagine a bubble

• If the bubble were about 10 light years across, it would contain about a dozen stars.
• If you keep enlarging the bubble to 1,000 light years across, then to 1 million light years, and then 1 billion light years, the farthest stars in the bubble will look even more faint.
• But there would also be more and more stars inside the bigger and bigger bubble, all of them contributing light.

Age matters

• Even though that’s an amazingly long time in human terms, it’s short in astronomical terms.
• It’s short enough that the light from stars more distant than about 13 billion light years hasn’t actually reached Earth yet.
• And so the actual bubble around Earth that contains all the stars we can see only extends out to about 13 billion light years from Earth.

The Doppler shift

• But that brings me back to the other thing I told you to imagine: that all of the stars are not moving.
• The universe is actually expanding, with the most distant galaxies moving away from Earth at nearly the speed of light.
• Because the galaxies are moving away so fast, the light from their stars is pushed into colors the human eye can’t see.
• This effect is called the Doppler shift.