Article Of The Day!

2023 September 18

The Red Sprite and the Tree Credit & Copyright: Maxime Villaeys

Explanation: The sprite and tree could hardly be more different. To start, the red sprite is an unusual form of lightning, while the tree is a common plant. The sprite is far away – high in Earth’s atmosphere, while the tree is nearby – only about a football field away. The sprite is fast – electrons streaming up and down at near light’s speed, while the tree is slow – wood anchored to the ground. The sprite is bright – lighting up the sky, while the tree is dim – shining mostly by reflected light. The sprite was fleeting – lasting only a small fraction of a second, while the tree is durable – living now for many years. Both however, when captured together, appear oddly similar in this featured composite image captured early this month in France as a thunderstorm passed over mountains of the Atlantic Pyrenees.

∞ Source: apod.nasa.gov/apod/ap230918.html

Wed. 9/25: We'll be closed tonight due to clouds. We'll try again next Wednesday!

We sure have been experiencing this around here. Not only has it affected temperatures, but the percentage of time the sky is cloudy. Our observatory takes images and hosts events less often in part because of the conditions of our sky.

So many people do not understand the relationship between climate change and cold weather.

Mosaic of the Eagle Nebula, June 6, 2015. Image Credit: Adam Gustafson | Jamie Kern | BSU Observatory.

Imaged in luminance and photometric R, V and B filters. Approximately 2 hours total exposure time.

The Eagle nebula is a stellar nursery where new stars are born. 

Mare Cognitum ("The Sea that has Become Known") with Kuiper crater at the center // l'AstroVan

Mare Cognitum ("The Sea that has Become Known") is the landing sites of several lunar missions. Ranger 7 (1964) impacted here after its mission was finished; Surveyor 3 (1967) and Apollo 12 (1969) landed near its northern shore; and Apollo 14 (1971) landed near this mare as well.

Kuiper crater is named after the Dutch-American astronomy Gerard Kuiper (1905-1973), the father of modern planetary science

Wed. 11/6: We'll be closed tonight - we expect lots of clouds rolling in after sunset. We'll try again next week!

Wed. 7/31: We'll be closed tonight due to clouds. Stay tuned for updates about August!

We were extremely fortunate to have Jocelyn Bell Burnell as a virtual guest in a women in science class! She was a pleasure to listen to and continues to be an inspiration.

Navigating Deep Space by Starlight

On August 6, 1967, astrophysicist Jocelyn Bell Burnell noticed a blip in her radio telescope data. And then another. Eventually, Bell Burnell figured out that these blips, or pulses, were not from people or machines.

The blips were constant. There was something in space that was pulsing in a regular pattern, and Bell Burnell figured out that it was a pulsar: a rapidly spinning neutron star emitting beams of light. Neutron stars are superdense objects created when a massive star dies. Not only are they dense, but neutron stars can also spin really fast! Every star we observe spins, and due to a property called angular momentum, as a collapsing star gets smaller and denser, it spins faster. It’s like how ice skaters spin faster as they bring their arms closer to their bodies and make the space that they take up smaller.

The pulses of light coming from these whirling stars are like the beacons spinning at the tops of lighthouses that help sailors safely approach the shore. As the pulsar spins, beams of radio waves (and other types of light) are swept out into the universe with each turn. The light appears and disappears from our view each time the star rotates.

After decades of studying pulsars, astronomers wondered—could they serve as cosmic beacons to help future space explorers navigate the universe? To see if it could work, scientists needed to do some testing!

First, it was important to gather more data. NASA’s NICER, or Neutron star Interior Composition Explorer, is a telescope that was installed aboard the International Space Station in 2017. Its goal is to find out things about neutron stars like their sizes and densities, using an array of 56 special X-ray concentrators and sensitive detectors to capture and measure pulsars’ light.

But how can we use these X-ray pulses as navigational tools? Enter SEXTANT, or Station Explorer for X-ray Timing and Navigation Technology. If NICER was your phone, SEXTANT would be like an app on it.  

During the first few years of NICER’s observations, SEXTANT created an on-board navigation system using NICER’s pulsar data. It worked by measuring the consistent timing between each pulsar’s pulses to map a set of cosmic beacons.

When calculating position or location, extremely accurate timekeeping is essential. We usually rely on atomic clocks, which use the predictable fluctuations of atoms to tick away the seconds. These atomic clocks can be located on the ground or in space, like the ones on GPS satellites. However, our GPS system only works on or close to Earth, and onboard atomic clocks can be expensive and heavy. Using pulsar observations instead could give us free and reliable “clocks” for navigation. During its experiment, SEXTANT was able to successfully determine the space station’s orbital position!

We can calculate distances using the time taken for a signal to travel between two objects to determine a spacecraft’s approximate location relative to those objects. However, we would need to observe more pulsars to pinpoint a more exact location of a spacecraft. As SEXTANT gathered signals from multiple pulsars, it could more accurately derive its position in space.

So, imagine you are an astronaut on a lengthy journey to the outer solar system. You could use the technology developed by SEXTANT to help plot your course. Since pulsars are reliable and consistent in their spins, you wouldn’t need Wi-Fi or cell service to figure out where you were in relation to your destination. The pulsar-based navigation data could even help you figure out your ETA!

None of these missions or experiments would be possible without Jocelyn Bell Burnell’s keen eye for an odd spot in her radio data decades ago, which set the stage for the idea to use spinning neutron stars as a celestial GPS. Her contribution to the field of astrophysics laid the groundwork for research benefitting the people of the future, who yearn to sail amongst the stars.  

Keep up with the latest NICER news by following NASA Universe on X and Facebook and check out the mission’s website. For more on space navigation, follow @NASASCaN on X or visit NASA’s Space Communications and Navigation website.  

Make sure to follow us on Tumblr for your regular dose of space!

Uranus and some of its moons on October 20, 2023 // Louis Fico

I think the moons in this image could be Titania, Umbriel, Ariel, and Oberon, tho which points of light they are is hard to say