Don’t Wait, You Need To See Comet NEOWISE Right Now

By now you’ve heard of NEOWISE, the most spectacular comet to visit our little corner of the galaxy since Hale-Bopp passed through over 20 years ago. But we’re willing to bet you haven’t actually seen it with your own eyes. That’s because up until now, the only way to view this interstellar traveler was to wake up in the pre-dawn hours; an especially difficult requirement considering a large chunk of the population has gotten used to sleeping-in over the last few months.

But things are about to change as NEOWISE begins a new phase of its trip through our celestial neck of the woods. Having come to within 44.5 million km (27.7 million miles) of the sun on July 3rd, the comet is now making its way back out of our solar system. Thanks to the complex dance of the heavens, that means that observers in the Northern Hemisphere will now be able to see NEOWISE in the evening sky just above the horizon.

NEOWISE is on a kind of “up and over” trajectory compared to the orbital paths of the planets. Get a better feel for it with JPL’s interactive solar dynamics tool.

While NEOWISE might be beating a hasty retreat from Sol right now, the comet it actually getting closer to us in the process. On July 22nd it will reach perigee, that is, the point in its orbit closest to Earth. On that evening the comet will be approximately 103 million km (64 million miles) away. Not exactly a stone’s throw, but pretty close in astronomical terms. The comet will appear to be getting higher in the sky as it approaches Earth, and should be visible with the naked eye between 10 and 20 degrees above the northern horizon.

Most estimates say that NEOWISE should remain visible until at least the middle of August, though it will be dimming rapidly. After that, you’re going to have to wait awhile for a repeat showing. Given the orbit of this particular comet, it won’t come around our way again for approximately 6,800 years, give or take a few lifetimes.

NASA will be hosting a NEOWISE live stream tomorrow afternoon where researchers will answer questions about this once in a lifetime celestial event, though we think you’ll get a lot more out of it if you just go outside and look up.

Maria Mitchell: The First Woman Astronomy Professor

On an October night in 1847, a telescope on the roof of the Pacific National Bank building on Nantucket Island was trained onto the deep black sky. At the eyepiece was an accomplished amateur astronomer on the verge of a major discovery — a new comet, one not recorded in any almanac. The comet, which we today know by the dry designator C/1847 T1, is more popularly known as “Miss Mitchell’s Comet,” named after its discoverer, a 29-year old woman named Maria Mitchell. The discovery of the comet would, after a fashion, secure her reputation as a scholar and a scientist, but it was hardly her first success, and it wouldn’t be her last by a long shot.

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How To Hack A Spacecraft To Die Gracefully

Last week, the Rosetta spacecraft crashed into comet 67P/Churyumov-Gerasimenko after orbiting it since 2014. It was supposed to do that: the mission was at an end, and the mission designers wanted to end it by getting a close look at the surface of the comet. But this raises an interesting problem: how do you get a device that is designed to never stop to actually stop?
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Listen To Meteors Live

When the big annual meteor showers come around, you can often find us driving up to a mountaintop to escape light pollution and watching the skies for a while. But what to do when it’s cloudy? Or when you’re just too lazy to leave your computer monitor? One solution is to listen to meteors online! (Yeah, it’s not the same.)

Meteors leave a trail of ionized gas in their wake. That’s what you see when you’re watching the “shooting stars”. Besides glowing, this gas also reflects radio waves, so you could in principle listen for reflections of terrestrial broadcasts that bounce off of the meteors’ tails. This is the basis of the meteor burst communication mode.

[Ciprian Sufitchi, N2YO] set up his system using nothing more than a cheap RTL-SDR dongle and a Yagi antenna, which he describes in his writeup (PDF) on meteor echoes. The trick is to find a strong signal broadcast from the earth that’s in the 40-70 MHz region where the atmosphere is most transparent so that you get a good signal.

This used to be easy, because analog TV stations would put out hundreds of kilowatts in these bands. Now, with the transition to digital TV, things are a lot quieter. But there are still a few hold-outs. If you’re in the eastern half of the USA, for instance, there’s a transmitter in Ontario, Canada that’s still broadcasting analog on channel 2. Simply point your antenna at Ontario, aim it up into the ionosphere, and you’re all set.

We’re interested in anyone in Europe knows of similar powerful emitters in these bands.

As you’d expect, we’ve covered meteor burst before, but the ease of installation provided by the SDR + Yagi solution is ridiculous. And speaking of ridiculous, how about communicating by bouncing signals off of passing airplanes? What will those ham radio folks think of next?

Hackaday 10th Anniversary: Hacking Your Way To NASA

[Steve] drives spacecraft for a living. As an engineer at the Jet Propulsion Laboratory, he’s guided probes to comets, asteroids, Mars, and Jupiter, figured out what happens when telemetry from these probes starts looking weird, and fills the role of the Space Hippy whenever NASA needs some unofficial PR.

Like most people who are impossibly cool, [Steve]’s career isn’t something he actively pursued since childhood. Rather, it’s something that fell in his lap. With qualifications like building a robotic computer to typewriter interface, a custom in-car navigation system in the late 80s, and a lot of work with an Amiga, we can see where [Steve] got his skills.

The earliest ‘hack’ [Steve] can remember was just that – an ugly, poorly welded sidecar for his bicycle made in his early teens. From there, he graduated to Lasertag landmines, Tesla coils, and building camera rigs, including a little bit of work on Octopussy, and a rig for a Miata. It helps when your dad is a cinematographer, it seems.

In college, [Steve] used his experience with 6502 assembler to create one of the first computerized lighting controllers (pre-DMX). After reading a biography on [Buzz Aldrin], [Steve] realized doing his thesis on orbital rendezvous would at least be interesting, if not an exceptionally good way to get the attention of NASA.

Around this time, [Steve] ran into an engineering firm that was developing, ‘something like Mathematica’ for the Apple II, and knowing 6502 assembly got him in the door. This company was also working to get the GPS constellation up and running, and [Steve]’s thesis on orbital mechanics eventually got him a job at JPL.

There’s several lifetimes worth of hacks and builds [Steve] went over at the end of his talk. The highlights include a C64 navigation system for a VW bug, a water drop high voltage machine, and a video editing system built from a few optical encoders. This experience with hacking and modding has served him well at work, too: when the star sensor for Deep Space 1 failed, [Steve] and his coworkers used the science camera as a stand in navigation aid.

One final note: Yes, I asked [Steve] if he played Kerbal Space Program. He’s heard of it, but hasn’t spent much time in it. He was impressed with it, though, and we’ll get a video of him flying around the Jool system eventually.