tag:blogger.com,1999:blog-3596550435682943926.post5238407861218805152..comments2023-01-05T02:20:45.223-08:00Comments on Hop's Blog: Inflated Delta VsHop Davidhttp://www.blogger.com/profile/12923433894475072056noreply@blogger.comBlogger8125tag:blogger.com,1999:blog-3596550435682943926.post-72986110547058750282019-10-13T13:36:00.140-07:002019-10-13T13:36:00.140-07:00Trident,
My lower delta Vs assume a capture orbit...Trident,<br /><br />My lower delta Vs assume a capture orbit with periapsis in the upper atmosphere. Which slows down the craft each periapse pass through the atmosphere. So aerobraking is already assumed in my numbers.Hop Davidhttps://www.blogger.com/profile/12923433894475072056noreply@blogger.comtag:blogger.com,1999:blog-3596550435682943926.post-43894671176337217302019-10-05T06:05:25.385-07:002019-10-05T06:05:25.385-07:00Hello,
I've just wanted to ask, whether it is...Hello,<br /><br />I've just wanted to ask, whether it is possible to reduce delta v even further by using aerocapture technology?<br /><br />Say you depart from Jupiter (from jupiter's capture orbit) and you are heading to Earth. Could you, instead of parking your spaceship on Earth's capture orbit, enter earth's atmosphere and slow down the ship putting it on LEO and then land on Earth. Could this reduce the delta v (Jupiter Earth) from your 3.5 km/sec to say 2km per sec or so?<br />tridenthttps://www.blogger.com/profile/09111455967752631556noreply@blogger.comtag:blogger.com,1999:blog-3596550435682943926.post-5596162335414519922015-04-11T09:43:15.466-07:002015-04-11T09:43:15.466-07:00Phil,
Cells J40 and J41 are apoapsis and periapsi...Phil,<br /><br />Cells <b>J40</b> and <b>J41</b> are apoapsis and periapsis circularize burns.<br /><br />Orbits are time reversible so these same burns are what it takes to go from the circular orbit to the elliptical orbit.<br /><br />For example, if I set earth periapsis at 300 and apoapsis at 9119690 (SOI altitude) I get circulize burns .5795 and 3.16. It'd cost 3.16 km/s to go from LEO to a 9119690 km altitude apogee.<br /><br />Likewise from a 911969 circular orbit, it would take .5795 km/s to dropp to a 300 km perigee.Hop Davidhttps://www.blogger.com/profile/12923433894475072056noreply@blogger.comtag:blogger.com,1999:blog-3596550435682943926.post-21309408344744680142015-04-10T17:39:46.072-07:002015-04-10T17:39:46.072-07:00Hi David,
Just playing with your spreadsheet in r...Hi David,<br /><br />Just playing with your spreadsheet in regard to min Dv Earth<>Mars using Capture orbits.<br /><br />Assuming aerobraking at each end, can the spreadsheet calc the ascent Dv necessary to entry the capture orbits at the Earth & Mars ends?<br /><br />If not can you please point me in the direction to find the ascent Dvs?<br /><br />Thanks,<br />PhilAnonymoushttps://www.blogger.com/profile/13892519012414037889noreply@blogger.comtag:blogger.com,1999:blog-3596550435682943926.post-57675726838444187752013-12-29T16:48:17.937-08:002013-12-29T16:48:17.937-08:00Thanks so much for the post and spreadsheet! Used ...Thanks so much for the post and spreadsheet! Used it as a reference for a project and gave me some ideas. Your work is much appreciated.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-3596550435682943926.post-68955279227398557612013-10-09T15:57:07.510-07:002013-10-09T15:57:07.510-07:00Interesting work, thanks for posting it. Adding an...Interesting work, thanks for posting it. Adding another chart for Earth's surface to those orbits or from LEO to those orbits would be handy as well, though both should just be a constant added to the existing chart.<br /><br />Mercury is interesting from a science fiction perspective in that it has polar volatiles and areas that maintain room temperature underground. Beyond the moon, it is the closest destination that has that.<br /><br />Regarding this: "However the axis of Uranus and her moons are tilted 97 degrees from the ecliptic. The plane change would be very expensive in terms of delta V. So the moons of Uranus wouldn't be helpful as propellant sources."<br /><br />Plane change delta-v only applies inside the system. You don't have to do a plane change to escape a moon of Uranus to Earth, nor to enter it. You lose the velocity you might have from the orbital velocity of the moon around the planet, but if you do burns to arrive and to leave then that's a wash.Ben Brockerthttps://www.blogger.com/profile/07288306199282855324noreply@blogger.comtag:blogger.com,1999:blog-3596550435682943926.post-44310312686798272292013-01-04T08:53:49.235-08:002013-01-04T08:53:49.235-08:00You're welcome.
I was surprised when I first ...You're welcome.<br /><br />I was surprised when I first calculated delta Vs from and to high apogee elliptical parking orbits. Didn't believe it at first and redid the calculations several times. I expect that's a common reaction.Hop Davidhttps://www.blogger.com/profile/12923433894475072056noreply@blogger.comtag:blogger.com,1999:blog-3596550435682943926.post-8244326890549911632012-12-09T14:10:22.913-08:002012-12-09T14:10:22.913-08:00Thanks for the post. . Helped me verify my numbers...Thanks for the post. . Helped me verify my numbers. CheersADiTHYA K Panihttps://www.blogger.com/profile/13263743085866161597noreply@blogger.com