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A chart of the height of the ISS:

Getting lower...

The ball is expected to remain in orbit for three to four years.

ISS loses about 2 KM of altitude per month if it doesn't use it's engines to gain some altitude (it's in a rather low orbit, so it does go through a tiny bit of our atmosphere, and this does slow it down) and if they ever did fail to gain altitude every few months, this drop would accelerate greatly as it got down more into our atmosphere. As a consequence of the square-cube law, smaller objects will generally drop even faster (because the ratio of surface area/mass increases as you get smaller, and so your deacceleration due to drag increases similarly.) Suitsat is probably a good deal less dense than a golf ball, and irregularly shaped, so it will certainly be much more draggy, and even though it's more massive I'd expect it to stay up for a shorter period of time, but even so ... a factor of 30 difference in how long they stay up seems awfully high.

Three to four years sounds like about how long the ISS would stay up without any thrust, but maybe it's longer than that. And a golf ball is pretty good at slipping through the air (that's what the dimples are all about) so maybe it's will stay up so long just because of that.

Or maybe Pavel Vinogradov has one hell of a swinging arm ...

http://heavens-above.com/ carries suitsat data.

I had my scanner programmed up (Uniden Bearcat 780XLT), I have a nice Dipole Antenna (Diamond D-130J), and a cron job setup to record whatever it heard according to Heavens Above. I'm tapped directly into the descriminator output (ie bypassing the crap audio processing)

I got nothing.

Thinking that I might be a little deaf, I ran the audio file through baudline to see if there was anything.

Nada. Just the normal sound card artifacts i get when recording static.

Now, I know I can hear something on this rig, and I know that I understand the graphs on Heavens Above as I was able to use the same setup to predict and capture some weak telemetry from the ISS a couple of days ago.

This was quite disappointing.

Next pass is coming up this afternoon - fingers crossed.

Does anyone know how much this is expected to suffer from doppler shift ? Looking at the ground tracks for this for Canberra, Australia its going to be moving fairly fast.

Hopefully my Bearcat 780 will get this on wideband FM

There are plenty of satellites visible by naked eye from earth. Check out thsi site for a satellite near you: http://www.heavens-above.com/

You don't even need an account. Here's the direct link.
http://www.heavens-above.com/issheight.asp

This isn't a good situation, but barring future disasters I'm confident that they'll get a ship up there to boost the ISS to a level where it can be saved for many more decades.

If you want to see the graphical representation of the ISS's altitude, there's a nice chart at Heavens-above.com It's a free sign-up, and the bonus is you can find out when ISS flies over your house so you can see it or even take pictures like I do sometimes.

I had noticed just a few days ago that the orbit was at its lowest point, and was getting concerned about what they were going to do about it.

To search for the next Iridium flare near you...
under Satellites, click 'next 7 days' under Iridium Flares.
You need to specify your location too.

heavens above

its big news.
Now i know how google is running at $274/share, and with PP ratio 120!
http://www.heavens-above.com/--Observe satellites that pass your place.

http://www.heavens-above.com/countries.asp

Better be quick though. It's getting prety light here on the east coast.
--
Fairfax Underground: Fairfax County message board and chat

Here is the CHEAP answer:
YES

You should have no trouble hearing the ISS, The Shuttle or any satellites using Ham Radio.

You need to know when to listen. Yes you can get keps and computer software and learn how to use it, however it's real easy for average Joe to just go to http://www.heavens-above.com/ and look it up. They tell you when and in what direction. ---It's great because you can see the ISS and other orbiting things too.

These satellites use several frequecies accross several bands. The most common ones you'd be interested in will be in the 2-Meter (145 MHz) and 70 centimeter (437 MHz) bands -as it's easy to get scanners that can pick up those frequencies. Luckily many of the satellites do transmit FM (as opposed to sideband or other mode) which is exactly what a cheap scanner likes.

You may hear voices! this makes it easy, because the scanner is all you need.

You may hear packet-splats --- when you hear them the term will make perfect sense.

You can hook the headphone jack of your scanner into the line in on your computer's sound card! There are many freeware OSS programs to decode it too. Sure, a dedicated Terminal Node Controller (TNC) is nice and even cheap, but free is always better when you're just playing with it to see what it is! info on using your soundcard for packet http://www.soundcardpacket.info/

You may want to know about other OSCARs out there (Orbital Satellite Carrying Amateur Radio) see: http://www.amsat.org/

Satellites aren't using high power, don't try to listen from your scanner with it's antenna in the basement -it won't work.

Use an external antenna if possible -It's a scanner not a transmitter, if all else fails, try a hunk of wire

Doppler shift... yes you heard me DOPPLER SHIFT... these things move fast! the signal may be off by more than 15kHz from where it's supposed to be... As the satellite approches, it will be higher, as it receeds it will be lower. It will be helpful to have a scanner that has a VFO... a way to rotate the dial and keep up with the satellite... otherwise program several channels 5 kHz apart both above and below the expected frequency so you can get to the next one quickly. Th more you can move in frequency to keep up with the satellite the longer you can hear it.

Downlinks
ISS: 145.800 MHz
PCSAT2: 437.975 MHz
AO-51: 435.300 MHz

What you hear -if anything- depends on what they are doing at the time. You aren't going to hear astronaut John Phillips, KE5DRY if he's having supper with the shuttle crew, or sleeping, or went home on a soyuz, or doing just about anything else. - Sometimes the satellites are shut off... while they fix it, or they experiment, they are on s-band or under power resrictions... whatever

Once you get some idea of when the sat will be overhead, you can start tuning around the transmit frequency. You have to keep the squelch open, and it helps to have a continuous tuning receiver because it is easier to adjust for doppler shift. I wouldn't think the NASA communications between the ISS and ground control is open for the general public (looks like the ground control systems are not easily heard by a scanner anyway), but the HAM stuff is all just narrowband FM. Good luck.

I was able to just paste some of my local viewing coordinates determined interactively at Heavens Above, a free star and satellite finder, into the input field for google maps. I found Stowe, Vermont but for Japan just got a total blank, with Japan's landmass in a solid color. It's a bug though because the world heritage urls do show you a limited res. kyoto, and also by typing in "tokyo" in the main maps.google.com/maps page you do get Tokyo, at res enough that you can zoom in on the imperial palace (oops!)

the iss is highly visible and very beautiful quite regularly. To find when it is visible at your location try Heavens Above.

I remember one night watching the ISS and one of the shuttles pass over together as the shuttle approached the station. It looked like two brilliant stars just a moon-width apart passing over head in perfect synchronization.

Spectacular sight! Everybody who sees this is impressed and amazed to think that there are people up there ...

Check out this guy who can summon UFOs on demand. Has a link to a news broadcast where they filmed him doing it. Shocked the hell out of the camera crew

Looks a whole lot like an iridium flare to me. Iridium flares are reflections of the sun off of satellites. Some flares can reach magnitude -8 or so, which is actually bright enough to be visible during the daytime.

It would be nice if the news crew had reported the date and time of the "sighting" so it could be cross-referenced with the predicted flares at heavens-above.com. Check out the site to catch a glimpse of flares visible in your area.

If you want to see the Space Station, it is making nice evening shows in the US right now. Just go to Heavens Above through your city in and watch it pass over.

It is as bright as the brightest star out there (Jupiter, yea not a star but you get it)

http://www.heavens-above.com/issheight.asp?lat=0&l ng=0&alt=0&loc=Unspecified&TZ=CET

I admit i was mistaken, but the ions per m3 could probably be counted on one hand... drag is still not the biggest issue, i think.

The only change here is that (a) they get to know who's accessing the data, and (b) those who access the data can't restribute it. This doesn't keep them from distributing the result of calculations based on the data, however.

Heavens-above.com has data regarding when satellites are visible from a given location on the earth's surface. I'm not sure if this gives any data on classified satellites. This site does currently still show orbital elements on the "orbit" page of each satellite's detail list - these are probably coming from non-Airforce tracking radars.

JTrack 3D is a great little java applet (warning, the applet loads in a separate window) that shows you a real-time view of near-earth space. You can even pull up description pages for each of the satellites shown. The "Launch/Orbital information" link on the detail page is broken, and seems to be the only part of this service affected. Again this is unlikely to ever have shown classified satellites.

Conspiracy theorists, take note. Every spacefaring nation on the planet knows where everything is in space including the orbital elements mentioned, to make sure thier expensive new pr0nosat won't crash into that random chunk of "damaged hardware that can't be de-orbited, oops" that's taking pictures of Osama's outhouse. This just keeps people from anonymously having the US Air Force do their orbit tracking for them.

Here's the problem: the new site not only forbids redistributing the keps (orbital parameters) to other people, which is a problem for /.-loved sites like http://www.heavens-above.com/ which tell you when things are coming overhead, but also forbids redistributing analysis based on the data. So if you have a business that's a subcontractor to a satellite operator, and your job is to analyse the orbital data and tell the satellite owner if they are drifting off station or something, then as of last week you are theoretically out of business. And even if you are using the data to provide very basic info on satellites that falls short of what you'd need to predict where the satellite is - like my newsletter at http://www.planet4589.org/ - it's not clear if you're even allowed to do that.

Now I suspect this is just a bureaucratic screwup, and the intent wasn't to be quite that restrictive. But there was way too little communication between the folks who wrote the law, the folks at USAF and NRO who understand which security concerns are real and which are bogus, and the different set of folks at USAF who run the orbital data service and had to interpret the law with very little guidance when writing up the new rules. In the absence of communication, things tend to be written to be so cover-your-ass that it gums up the works and that's what is happening.

No orbital information means that you can't make and especially share satellite observation forecasts with your friends

Site like Heavens Above will need alternate source to make their forecast. This is a shame, accurate forecasts were a bonus to amateur observers and essential to observe some satellites.

Those who haven't observed a -8 Iridium are missing something. They are spectacular

Sure, you claim your only motivation was to show the audience something new. But people don't really need a group lesson and nifty pointers to learn where comet Machholz or the Andromeda Galaxy are- they should search them out on their own. And ditto with Slashdot. Did you think about what happens when millions of (in)coherent eyeballs go slamming against a website all at once? That site can go down for minutes or hours- customers could be bounced; money could be lost (and as time is money and everyone has only so much time, really, lives could be lost...).

In fact, anytime you bring too much attention to any one site or any one person you could be distracting them and keeping them from doing their necessary work. That's almost as bad as FOIA requests. If only the PATRIOT Act existed before Woodward and Bernstein: they'd have been lucky to only face 25 years. (sarcasm mode off)

Thanks to www.heavens-above.com
Checkout this handy guide: Comet Machhholz(C/2004 Q2)
It helps if you first register your observing location.

Thanks to www.heavens-above.com
Checkout this handy guide: Comet Machhholz(C/2004 Q2)
It helps if you first register your observing location.

Does anyone know where to look

The Iridium flares are quite spectacular -- extremely bright if you're in the right place at the right time.

Has this effect been observed as to the Voyagers?

Excellent illustration (updated daily!) of all these probes and their vitals (trajectories, distance, speed, etc.) at Heavens-Above .

It is possible, however, to use inclined orbits to provide good coverage at high latitudes, including the poles. You'll need multiple satellites to provide continuous coverage, though. It's my understanding that the South Pole links use retired geostationary satellites that have run out of stationkeeping propellant. Without stationkeeping, solar and lunar perturbations increase the orbital inclination, the angle between the orbital plane and the equator, which is nominally zero for a geostationary satellite. This causes the satellite to move in a north-south figure-8 pattern, making it visible for part of each day at each pole.

Two good examples of satellites in orbits specifically designed to provide good high latitude coverage are the Russian Molniya series and the new Sirius digital radio broadcasting satellites. (Sirius' competitor XM Radio uses conventional geostationary satellite orbits.)

Both Molniya and Sirius use elliptical orbits with inclinations of about 63 degrees. At this inclination, the effect of the earth's oblateness on the orbital argument of perigee is canceled out. That means the apogee (farthest point from the earth) will always occur at the same latitude, which in these two cases is selected to be the northernmost point of the orbit (since northern latitudes are being served). The result is a satellite that, while not stationary, spends much of each orbit nearly motionless at high latitude.

The Molniya and Sirius orbits differ in that the Molniya orbits have fairly low perigees and orbital periods of about 12 hours. The Sirius satellites are in geosynchronous (but not geostationary) orbits, meaning that even though they do not sit motionless over the equator, they still complete exactly one orbit per sidereal earth day.

The Russians use these orbits because their country sits at high latitudes. Sirius uses their orbits to increase the elevation at which their satellites appear over the northern US and southern Canada, minimizing blockage by buildings and reducing the number of terrestrial repeaters needed in urban areas.

A Sirius orbit can be seen here and a Molniya orbit can be seen here.

It is possible, however, to use inclined orbits to provide good coverage at high latitudes, including the poles. You'll need multiple satellites to provide continuous coverage, though. It's my understanding that the South Pole links use retired geostationary satellites that have run out of stationkeeping propellant. Without stationkeeping, solar and lunar perturbations increase the orbital inclination, the angle between the orbital plane and the equator, which is nominally zero for a geostationary satellite. This causes the satellite to move in a north-south figure-8 pattern, making it visible for part of each day at each pole.

Two good examples of satellites in orbits specifically designed to provide good high latitude coverage are the Russian Molniya series and the new Sirius digital radio broadcasting satellites. (Sirius' competitor XM Radio uses conventional geostationary satellite orbits.)

Both Molniya and Sirius use elliptical orbits with inclinations of about 63 degrees. At this inclination, the effect of the earth's oblateness on the orbital argument of perigee is canceled out. That means the apogee (farthest point from the earth) will always occur at the same latitude, which in these two cases is selected to be the northernmost point of the orbit (since northern latitudes are being served). The result is a satellite that, while not stationary, spends much of each orbit nearly motionless at high latitude.

The Molniya and Sirius orbits differ in that the Molniya orbits have fairly low perigees and orbital periods of about 12 hours. The Sirius satellites are in geosynchronous (but not geostationary) orbits, meaning that even though they do not sit motionless over the equator, they still complete exactly one orbit per sidereal earth day.

The Russians use these orbits because their country sits at high latitudes. Sirius uses their orbits to increase the elevation at which their satellites appear over the northern US and southern Canada, minimizing blockage by buildings and reducing the number of terrestrial repeaters needed in urban areas.

A Sirius orbit can be seen here and a Molniya orbit can be seen here.

This ESA page will give a personal timetable for ISS spotting.

We're both wrong, it's more like 1.765 AU, or 264 million km.

Cel phone service by satellite - how could it lose? Seamless coverage everywhere on the globe.

Turned out that after launching 72 Iridium satellites Motorola found themselves very broke.

Is it possible that Sirius and XM will find the same thing - that the demand for pay as you go radio is significantly less than hoped? 1.2 million subscribers is a pretty small base to support the kind of technology they need.

Still not convinced that cells in a rotating bio-reactor are a good model for cells in an in vivo micro-gravitational environment, but at least "modeled micro-graviity" makes sense now!

Actually, the whole thing is discussed on the NASA page.

My question is one of money and priorities. While they're concerned about the shear effects, which don't take place in "real" microgravity, it seems like there would be better uses for the ISS' mass budget than an experiment which can be replicated to a large extent on the ground.

On the other hand, with only two crew members, the ISS isn't doing much these days other than maintaining its attitude. I guess an experiment like this, with minimal crew attention required, is all we can hope to achieve.

I'm rooting for the Chinese space program to start a new space race... 'cause until someone finds (and deploys) a way to make real money from manned space, the only space exploration my kids will be part of is watching communications satellites fly overhead.

Well, you could follow the mission even by yourself with the aid of resources like Heavens Above databases (obviously that orbit display isn't accurate anymore since they've landed already...)

Login to heavens-above.com . After you're logged in, click on "Shenzhou 5". It will show you visibility times for your location and its current position (unfortunately for me, it won't be visible before it de-orbits).

Look up the concept of "Iridium flares." Solar panels are a little bit amber, and when you're at just the right angle, they produce the sort of flashes you describe.

http://www.heavens-above.com/ is one resource, with tracking/observation-timing data for those too lazy to run their own programs. (Like me.)

Voor diegene die dit nog niet kunnen volgen:

Telstar 4: Een TV sataliet (Afbeelding hier maar de echte slashdotter kan hem in het echt zien zolang je maar weet Waar en waneer)

"CW carriers up on 11700 MHz V & 12200 MHz H": Een CW carrier is niet zomaar een draaggolf, het is een draagolf met een morsecode er op! (foei mister berg CW staat hier voor continuous wave), de V en de H geven de polarisatie aan.

Loral Skynet : Uitbater van de Skynet satalieten die een groot deel van de wereld van TV voorzien.

"orbital slot": Een locatie op een baan boven de evenaar (voor geostationaire satalieten)

I assume Wouter (The parent poster) and I are both equally delighted te be have found a home away from tweakers.net, which carries mainly bad translations (To dutch for those still wondering) of slashdot items... I better shut up now, voor ik een bende power-koeien achter mij aan krijg.

1) The IIS is low orbit, that means that every now and then you have to boost it back to higher altitudes. That is expensive (fuel) and expense increases with the load attached.

2) As for hauling the Hubble, it is on a much higher orbit, enough higher that it is not feasible, even if it was desirable

3) GPS sats are NOT geo-sync. Geo-sync sats are those that maintain the same position relative to a point in Earth's surface. The TV and comm sats are examples of those. Their orbits are all over the equator line, and several thousand miles high.

You'd be wanting this then. Will find you any satellite by location, time, direction, and brightness. Also lets you find the Iridium flashes (visible in daylight!)

-T

If you want any info on the Sun, other stars, satellites, planets, Iridium Flares, etc ...

Heavens Above is a good place to start.

[...] technically the shuttle is not an irreplaceable part of the ISS program.

Unfortunately, this isn't correct. When the shuttle is docked, it fires its thrusters to boost the station to a higher orbit. Because the station orbits so low, air resistance gradually drops the altitude. Without the boosts, the station will re-enter and crash.

Unfortunately, the Soyuz/Progress system can't deliver adequate thrust. You can check out the altitude data.

If you haven't already seen one, Iridium Flares are really quite impressive.

Russia has problems that plague the USA, and NASA. Just a few months ago, a person on the ground was killed when a Proton rocket exploded when launched. Less than 20 years ago, NASA lost 7 people to the Challenger disaster. I don't think Russia has any greater problems than NASA.
In fact I think it is wonderful that they are given the oportunity to contribute to a world class effort like the ISS. Go and look at it.. There isn't anything more spectacular in the space program than that, for the moment. Missions to the Moon are a long way off for NASA.
The discussion of space exploration always brings out the whiners about how much money it is costing, when it could be feeding the hungry. Oh, yeah? So could all the money put into the tobacco industry, and canceling cigarettes would actually benefit mankind, not removing our link to space.

Michael

1. Even if they make a satellite with 1 mm resolution, it still couldn't read a license plate because license plates are vertical. When the guv'ment requires license plates on the TOPs of our cars, we will know they have the resolution. 2. Also, most satellites are not geo-synchronous, so they are only over a single spot every so-many orbits. It's not like they can "follow" a fleeing thief. To find a satellite's orbit, try looking here. 3. Various optics effects cause limitations due to atmosphere, wavelengths, diffraction, etc.

• Mars will get 1.20 times closer to the Sun. That makes it 1.20^2 = 1.44 times brighter.
  
• Mars will get 6.54 times closer to the Earth. That makes it 6.54^2 = 42.77 times brighter.
  
• Mars is currently a 72% crescent, but will become ~100% full, which means 1/0.72 = 1.39 times brighter.

• Mars will get 1.20 times closer to the Sun. That makes it 1.20^2 = 1.44 times brighter.
  
• Mars will get 6.54 times closer to the Earth. That makes it 6.54^2 = 42.77 times brighter.
  
• Mars is currently a 72% crescent, but will become ~100% full, which means 1/0.72 = 1.39 times brighter.

Try it for yourself. It is very neat to watch this fly overhead, and if you like I can email you pictures of it wizzing over me.
You just tell it where you live.

Hear hear! One early morning I happened to see the station flying across the sky and it was amazing to realize that that little moving "star" was something that mankind managed to brought up there, high in space. For those who can't appreciate it, find out when the ISS is going to fly by and experience it for yourself.

http://heavens-above.com/ has location-based information about the flight path of the ISS, among other things. Worth a visit.

Here's an even better site: Heavens Above.

It covers any location in the world (not just USA and Canada). It has fly-by data for hundreds of satellites (including ISS) and my personal favorites, the Iridium flares. If you've never seen a -7 magnitude Iridium flare, do yourself a favor and check it out. It's absolutely awesome.

Heavens Above will tell you where to look (direction and azimuth) and when to look - accurate down to the second!